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Saline Laxatives (Monograph)

Brand names: Ceo-Two, Fleet Enema, Fleet Pedia-Lax, OsmoPrep, Phillips' Milk of Magnesia
Drug class: Cathartics and Laxatives
ATC class: A06AX02
VA class: GA200
CAS number: 124-38-9

Warning

    Renal Effects Associated with Oral Sodium Phosphates Preparations
  • Renal failure, acute phosphate nephropathy, and nephrocalcinosis reported rarely with oral sodium phosphates preparations (e.g., oral solution, OsmoPrep tablets) used for bowel cleansing.212 213 220 221 236 238 239 283 b Often resulted in permanent renal function impairment and sometimes required long-term dialysis.212 213 283 (See Renal Effects under Cautions.)

  • Risk of acute phosphate nephropathy may be increased in patients with increased age (>55 years of age), hypovolemia, increased bowel transit time (e.g., bowel obstruction), active colitis, baseline renal disease, or known or suspected electrolyte disturbances (e.g., dehydration),220 and in patients receiving drugs that affect renal perfusion or function (e.g., diuretics, ACE inhibitors, angiotensin II receptor antagonists, possibly NSAIAs).212 213 220 239 240 283

  • Importance of adherence to recommended dosage and dosing regimen.283

Introduction

Laxatives containing magnesium cations or phosphate anions.a

Uses for Saline Laxatives

Constipation

Used to relieve occasional constipation.214 215 216 217 218 219 220 224 225 227 231 b

Use of saline laxatives for simple constipation is seldom necessary or desirable; bulk-forming laxatives are drugs of choice.b

Do not use rectal suppositories or enemas if oral laxatives are effective.b

Mild saline laxatives (e.g., oral magnesium hydroxide, milk of magnesia) have been used to treat constipation during pregnancy or the puerperium; bulk-forming laxatives or stool softeners preferred.b

Used rectally, after administration of a stool softener or mineral oil, to evacuate the impacted colon in the treatment of constipation associated with stricture of the colon or fecal impaction.b Alternatively, administer phosphate-containing saline enemas rectally after manual disimpaction to promote evacuation of fecal impactions.b

Bowel Cleansing

Used orally and/or rectally (as suppositories or enemas) to empty the bowel prior to surgery or radiologic, proctoscopic, or endoscopic procedures, when thorough evacuation is essential.212 213 219 220 221 222 223 227 232 b

FDA recommends using oral sodium phosphates preparations for bowel cleansing only when a prescription for such use has been issued by a clinician.239 240 (See Renal Effects under Cautions.)

Poisonings

May hasten removal of some poisons [off-label] from the GI tract after inducing emesis or performing gastric lavage.b Not for use after poisonings with ingested acids or alkalies.b Magnesium laxatives should not be used to remove poisons that produce CNS depression or renal function impairment.b

Saline Laxatives Dosage and Administration

General

Administration

Administer magnesium-containing saline laxatives orally as chewable tablets, suspensions, or solutions.215 216 217 218 222 223 224 225 232

Administer phosphate-containing laxatives orally as solutions or tablets and rectally as enemas.212 213 219 220 221 227 228 229 230 Do not administer commercially available phosphate-containing rectal enema solutions orally.219 227 228

Administer carbon dioxide-releasing suppositories (e.g., CEO-TWO) rectally.214

Select rectal phosphate-containing laxatives carefully to ensure appropriate volume for age to minimize risk of overdosage.219 227 228

Administer laxatives as infrequently as possible at the lowest effective dosage level.b Do not use for >7 days unless directed by prescriber.215 216 b FDA states that sodium phosphates preparations should not be used for self-medication of occasional constipation for >3 days.279

Administer laxatives with sufficient fluids (i.e., 240 mL) to prevent dehydration from repeated administration.215 216 217 218 224 225 233 b (See Fluid Intake under Cautions.)

Oral Administration

Administer orally as magnesium-containing chewable tablets, suspensions, or solutions or as phosphate-containing solutions or tablets.212 213 215 216 217 218 219 220 221 222 223 224 225 227 228 229 230 232 233 235 Drink a full (240 mL) glass of clear liquid (e.g., water) following administration of each dose.215 216 217 218 224 225 233 275 283

Do not administer fixed combination of magnesium hydroxide and mineral oil with meals; typically administered at bedtime.218

Shake suspensions well before use.215 216 218

May refrigerate oral sodium phosphates solutions to improve taste;220 may drink magnesium citrate chilled.222

Use sodium phosphates tablets with caution in patients with impaired gag reflex and those prone to regurgitation or aspiration; observe these patients during administration of tablets.283

Reconstitution (Magnesium Sulfate Crystals)

To prepare magnesium sulfate oral solution, dissolve appropriate dose of the crystals in at least 240 mL water; may add lemon juice to mask bitter taste and minimize nausea.225 b

Dilution

Dilute sodium phosphates oral solution prior to administration.220 229 230 When used as a laxative for self-medication of occasional constipation, mix appropriate dose of the solution with 240 mL of cool water.275

Rectal Administration

Administer rectally as phosphate-containing enemas or carbon dioxide-releasing suppositories.214 219 227 228

Suppositories

Carbon dioxide-releasing suppositories: Remove wrapper and moisten under a warm-water tap for 30 seconds or in a cup of water for ≥10 seconds prior to rectal insertion;214 231 234 do not use mineral oil or petroleum jelly to lubricate.214 231 234

Insert suppository high into the rectum past the largest diameter of the suppository;214 retain for as long as possible (usually 5–30 minutes) before defecating.214 231 b

Enemas

Administer sodium phosphates enema at room temperature.219 Drink additional liquid during therapy to ensure adequate hydration.280

Remove protective shield (if present) from tip of enema.219 228

Before administering, lie on left side with knees bent or kneel on the bed with head and chest lowered and forward until the left side of the face is resting on the surface of the bed.219 228 b

With steady pressure, insert enema nozzle into rectum, with nozzle pointed toward the navel.219 b To ease insertion, have patient bear down as if having a bowel movement.219 Squeeze container until nearly all the liquid is expelled.219 228 b Use caution to avoid bowel perforation.219 If resistance is encountered during insertion or administration, discontinue procedure to avoid perforation or rectal abrasion.219

Retain until definite lower abdominal cramping felt.b Complete evacuation of the left colon usually occurs within 1–5 minutes.219

Disposable enemas are for single-use only.219

For children 2–4 years of age, prepare an enema containing dibasic sodium phosphate 1.75 g and monobasic sodium phosphate 4.75 g in approximately 29 mL for administration as follows.227 Unscrew the cap of a pediatric-strength enema containing dibasic sodium phosphate 3.5 g and monobasic sodium phosphate 9.5 g in 59 mL (e.g., Fleet Pedia-Lax Enema) and remove 30 mL of solution.227 Replace the cap and administer the enema as directed.227

Dosage

Most studies suggest that the minimum effective oral laxative dose of magnesium is 80 mEq.a (See Electrolytic Content under Cautions.)

Magnesium sulfate crystals: Each level teaspoonful of crystals provides approximately 5 g of magnesium sulfate and 495 mg (40.7 mEq) of magnesium.225

Sodium phosphates enemas: A 66-mL enema (Fleet Pedia-Lax Enema) delivers a dose of 3.5 g of dibasic sodium phosphate and 9.5 g of monobasic sodium phosphate in 59 mL;227 a 133-mL enema (Fleet Enema) delivers a dose of 7 g of dibasic sodium phosphate and 19 g of monobasic sodium phosphate in 118 mL; a 230-mL enema (Fleet Enema Extra) delivers a dose of 7 g of dibasic sodium phosphate and 19 g of monobasic sodium phosphate in 197 mL.219

Pediatric Patients

Constipation

Laxatives should be used as infrequently as possible, at the lowest effective dosage level, and usually for ≤7 days; laxatives should be used for longer periods only under the management of a clinician and as part of a carefully planned therapeutic regimen.214 215 216 217 218 219 220 221 223 225 232 (See Chronic Use or Overdosage under Cautions.)

Magnesium Citrate
Oral

Children 2–5 years of age: For self-medication, 2.7–6.25 g (usually 60–90 mL [3.5–5.25 g] of a 291-mg/5-mL oral solution224 ) as a single daily dose or in divided doses.234

Children 6–11 years of age: For self-medication, 5.5–12.5 g (usually 90–150 mL [5.25–8.75 g] of a 291-mg/5-mL oral solution224 ) as a single daily dose or in divided doses.234

Children ≥12 years of age: For self-medication, 8.75–25 g (usually 150–300 mL [8.75–17.5 g] of a 291-mg/5-mL oral solution224 ) as a single daily dose or in divided doses.234

Magnesium Hydroxide
Oral

Children 2–5 years of age: For self-medication, 0.4–1.2 g daily given as a single dose (preferably at bedtime), in divided doses, or as directed by a clinician.217 233 234 235

Children 6–11 years of age: For self-medication, 1.2–2.4 g daily given as a single dose (preferably at bedtime), in divided doses, or as directed by a clinician.215 216 217 218 233 234 235

Children ≥12 years of age: For self-medication, 2.4–4.8 g daily given as a single dose (preferably at bedtime), in divided doses, or as directed by a clinician.215 216 217 218 233 234

Magnesium Sulfate
Oral

Children 2–5 years of age: For self-medication, 2.5–5 g daily given as a single dose or in divided doses.234

Children 6–11 years of age: For self-medication, 5–10 g daily given as a single dose or in divided doses.225 234

Children ≥12 years of age: For self-medication, 10–30 g daily given as a single dose or in divided doses.225 234

Fixed Combination of Magnesium Hydroxide and Mineral Oil
Oral

Do not use manufacturer's provided dosage cup for Phillips' M-O for children.218

Children 6–11 years of age: For self-medication, 1.2–1.8 g of magnesium hydroxide (20–30 mL of the fixed-combination suspension) daily given as a single dose (at bedtime), in divided doses, or as directed by a clinician.218

Children ≥12 years of age: For self-medication, 2.7–3.6 g of magnesium hydroxide (45–60 mL of the fixed-combination suspension) daily given as a single dose (at bedtime), in divided doses, or as directed by a clinician.218

Sodium Phosphates Enemas
Rectal

Do not administer adult-size Fleet enemas to children <12 years of age.219 Do not administer a full 59-mL Fleet Pedia-Lax Enema to children <5 years of age.219 227

Children 2–4 years of age: For self-medication, 1.75 g of dibasic sodium phosphate and 4.75 g of monobasic sodium phosphate (½ bottle [approximately 29 mL] of Fleet Pedia-Lax Enema) given as a single daily dose.227 To obtain correct dose, remove 30 mL liquid from Fleet Pedia-Lax Enema prior to administration.227

Children 5–11 years of age: For self-medication, 3.5 g of dibasic sodium phosphate and 9.5 g of monobasic sodium phosphate (1 bottle [approximately 59 mL] of Fleet Pedia-Lax Enema) given as a single daily dose or as directed by a clinician.227

Children ≥12 years of age: For self-medication, 7 g of dibasic sodium phosphate and 19 g of monobasic sodium phosphate (1 bottle of Fleet Enema [approximately 118 mL] or Fleet Enema Extra [approximately 197 mL]) given as a single daily dose.219 228

Sodium Phosphates Oral Solution
Oral

Children 5–9 years of age: For self-medication, 1.35 g of dibasic sodium phosphate and 3.6 g of monobasic sodium phosphate given as a single daily dose.275

Children ≥10 years of age: For self-medication, 2.7 g of dibasic sodium phosphate and 7.2 g of monobasic sodium phosphate given as a single daily dose.275

Carbon Dioxide-releasing Suppositories
Rectal

Children ≥12 years of age: For self-medication, 1 suppository (0.9 g potassium bitartrate and 0.6 g sodium bicarbonate) given as a single daily dose.214 231 234

Bowel Cleansing

Consult a clinician for details (e.g., time of administration) of the specific regimen to be used to clear the bowel prior to surgical, radiologic, or endoscopic procedures.222 223 226 232

Fleet Sodium Phosphates Enemas
Rectal

Do not administer adult-size Fleet enemas to children <12 years of age.219 Do not administer a full 59-mL Fleet Pedia-Lax Enema to children <5 years of age.219 227

Children 2–4 years of age: For self-medication, 1.75 g of dibasic sodium phosphate and 4.75 g of monobasic sodium phosphate (½ bottle [approximately 29 mL] of Fleet Pedia-Lax Enema) given as a single daily dose.227 281 To obtain correct dose, remove 30 mL liquid from Fleet Pedia-Lax Enema prior to administration.227 281

Children 5–11 years of age: For self-medication, 3.5 g of dibasic sodium phosphate and 9.5 g of monobasic sodium phosphate (1 bottle [approximately 59 mL] of Fleet Pedia-Lax Enema) given as a single daily dose or as directed by a clinician.227 281

Children ≥12 years of age: For self-medication, 7 g of dibasic sodium phosphate and 19 g of monobasic sodium phosphate (1 bottle of Fleet Enema [approximately 118 mL] or Fleet Enema Extra [approximately 197 mL]) given as a single daily dose.219 228 281

Adults

Constipation

Laxatives should be used as infrequently as possible, at the lowest effective dosage level, and usually for ≤7 days; laxatives should be used for longer periods only under the management of a clinician and as part of a carefully planned therapeutic regimen.214 215 216 217 218 219 220 221 223 225 232 b (See Chronic Use or Overdosage under Cautions.)

Magnesium Citrate
Oral

For self-medication: 8.75–25 g (usually 150–300 mL of a 291-mg/5-mL oral solution224 ) as a single daily dose or in divided doses.234

Magnesium Hydroxide
Oral

For self-medication: 2.4–4.8 g daily given as a single dose (preferably at bedtime), in divided doses, or as directed by a clinician.215 216 217 218 233 234

Magnesium Sulfate
Oral

For self-medication: 10–30 g daily given as a single dose or in divided doses.225 234

Fixed Combination of Magnesium Hydroxide and Mineral Oil
Oral

For self-medication: 2.7–3.6 g of magnesium hydroxide (45–60 mL of the fixed-combination suspension) daily given as a single dose (at bedtime), in divided doses, or as directed by a clinician.218

Sodium Phosphates Enemas
Rectal

For self-medication: 7 g of dibasic sodium phosphate and 19 g of monobasic sodium phosphate (1 bottle of Fleet Enema [approximately 118 mL] or Fleet Enema Extra [approximately 197 mL]) given as a single daily dose.219 228

Sodium Phosphates Oral Solution
Oral

For self-medication: 2.7 g of dibasic sodium phosphate and 7.2 g of monobasic sodium phosphate given as a single daily dose.275

Carbon Dioxide-releasing Suppositories
Rectal

1 suppository (0.9 g potassium bitartrate and 0.6 g sodium bicarbonate) given as a single daily dose.214 231 234

Bowel Cleansing
Sodium Phosphates Enemas
Rectal

For self-medication: 7 g of dibasic sodium phosphate and 19 g of monobasic sodium phosphate (1 bottle of Fleet Enema [approximately 118 mL] or Fleet Enema Extra [approximately 197 mL]) given as a single daily dose.219 228 281

OsmoPrep Sodium Phosphates Tablets
Oral

Evening before procedure: 1.592 g of dibasic sodium phosphate and 4.408 g of monobasic sodium phosphate (4 tablets) with 240 mL clear liquids; repeat every 15 minutes for 5 doses.213 Total dose 7.96 g of dibasic sodium phosphate and 22.04 g of monobasic sodium phosphate (20 tablets).213

Day of procedure: 1.592 g of dibasic sodium phosphate and 4.408 g of monobasic sodium phosphate (4 tablets) with 240 mL clear liquids every 15 minutes beginning 3–5 hours before the procedure.213 Repeat every 15 minutes for 3 doses.213 Total dose 4.776 g of dibasic sodium phosphate and 13.224 g of monobasic sodium phosphate (12 tablets).213

Total dosage is 12.736 g of dibasic sodium phosphate and 35.264 g of monobasic sodium phosphate with 1892 mL (2 quarts) of clear fluids.213 No additional enema or laxative is required.213

Prescribing Limits

Pediatric Patients

Constipation

Laxatives should not be used for self-medication of constipation for ≥7 days without consulting clinician.214 215 216 217 218 219 220 221 223 225 231 232 b

Magnesium Citrate
Oral

Children 2–5 years of age: For self-medication, maximum 6.25 g (usually <90 mL [5.25 g] of a 291-mg/5-mL oral solution) daily.224 234

Children 6–11 years of age: For self-medication, maximum 12.5 g (usually <150 mL [8.75 g] of a 291-mg/5-mL oral solution) daily.224 234

Children ≥12 years of age: For self-medication, maximum 25 g (usually <300 mL [17.5 g] of a 291-mg/5-mL oral solution) daily.224 234

Magnesium Hydroxide
Oral

Children 2–5 years of age: For self-medication, maximum 1.2 g daily.217 233 234 235

Children 6–11 years of age: For self-medication, maximum 2.4 g daily.215 216 217 218 233 234 235

Children ≥12 years of age: For self-medication, maximum 4.8 g daily.215 216 217 218 233 234

Magnesium Sulfate
Oral

Children 2–5 years of age: For self-medication, maximum 5 g daily.234

Children 6–11 years of age: For self-medication, maximum 10 g daily.225 234

Children ≥12 years of age: For self-medication, maximum 30 g daily.225 234

Fixed Combination of Magnesium Hydroxide and Mineral Oil
Oral

Children 6–11 years of age: Maximum 1.8 g of magnesium hydroxide (30 mL of the fixed-combination suspension) daily.218

Children ≥12 years of age: Maximum 3.6 g of magnesium hydroxide (60 mL of the fixed-combination suspension) daily.218

Sodium Phosphates Enemas
Rectal

Children 2–4 years of age: For self-medication, maximum 1.75 g of dibasic sodium phosphate and 4.75 g of monobasic sodium phosphate (½ bottle [approximately 29 mL] of Fleet Pedia-Lax Enema) in 24 hours.227

Children 5–11 years of age: For self-medication, maximum 3.5 g of dibasic sodium phosphate and 9.5 g of monobasic sodium phosphate (1 bottle [approximately 59 mL] of Fleet Pedia-Lax Enema) in 24 hours.227

Children ≥12 years of age: For self-medication, maximum 7 g of dibasic sodium phosphate and 19 g of monobasic sodium phosphate (1 bottle of Fleet Enema [approximately 118 mL] or Fleet Enema Extra [approximately 197 mL]) in 24 hours.219 228

Do not exceed maximum recommended dosage.279 Additional doses not recommended within 24 hours, even if no bowel movement occurs after a dose.279 (See Chronic Use or Overdosage under Cautions.)

Do not use for self-medication of occasional constipation for >3 days.279

Sodium Phosphates Oral Solution
Oral

Children 5–9 years of age: For self-medication, maximum 1.35 g of dibasic sodium phosphate and 3.6 g of monobasic sodium phosphate (given as a single daily dose) in 24 hours.275

Children 10–11 years of age: For self-medication, maximum 2.7 g of dibasic sodium phosphate and 7.2 g of monobasic sodium phosphate (given as a single daily dose) in 24 hours.275

Children ≥12 years of age: For self-medication, maximum 8.1 g of dibasic sodium phosphate and 21.6 g of monobasic sodium phosphate (given as a single daily dose) in 24 hours.275

Do not exceed maximum recommended dosage.279 Additional doses not recommended within 24 hours, even if no bowel movement occurs after a dose.279 (See Chronic Use or Overdosage under Cautions.)

Do not use for self-medication of occasional constipation for >3 days.279

Bowel Cleansing
Sodium Phosphates Enemas
Rectal

Children 2–4 years of age: For self-medication, maximum 1.75 g of dibasic sodium phosphate and 4.75 g of monobasic sodium phosphate (½ bottle [approximately 29 mL] of Fleet Pedia-Lax Enema) in 24 hours.227

Children 5–11 years of age: For self-medication, maximum 3.5 g of dibasic sodium phosphate and 9.5 g of monobasic sodium phosphate (1 bottle [approximately 59 mL] of Fleet Pedia-Lax Enema) in 24 hours.227

Children ≥12 years of age: For self-medication, maximum 7 g of dibasic sodium phosphate and 19 g of monobasic sodium phosphate (1 bottle of Fleet Enema [approximately 118 mL] or Fleet Enema Extra [approximately 197 mL]) in 24 hours.228

Adults

Constipation

Laxatives should not be used for self-medication of constipation for ≥7 days without consulting clinician.214 215 216 217 218 219 220 221 223 225 231 232 b

Magnesium Citrate
Oral

For self-medication: Maximum 25 g (usually 300 mL [17.5 g] of a 291-mg/5-mL oral solution) daily.224 234

Magnesium Hydroxide
Oral

For self-medication: Maximum 4.8 g daily.215 216 217 218 233 234

Magnesium Sulfate
Oral

For self-medication: Maximum 30 g daily.225 234

Fixed Combination of Magnesium Hydroxide and Mineral Oil
Oral

For self-medication: Maximum 3.6 g of magnesium hydroxide (60 mL of the fixed-combination suspension) daily.218

Sodium Phosphates Enemas
Rectal

For self-medication: Maximum 7 g of dibasic sodium phosphate and 19 g of monobasic sodium phosphate (1 bottle of Fleet Enema [approximately 118 mL] or Fleet Enema Extra [approximately 197 mL]) in 24 hours.219 228

Do not exceed maximum recommended dosage.279 Additional doses not recommended within 24 hours, even if no bowel movement occurs after a dose.279 (See Chronic Use or Overdosage under Cautions.)

Sodium Phosphates Oral Solution
Oral

For self-medication: Maximum 8.1 g of dibasic sodium phosphate and 21.6 g of monobasic sodium phosphate (given as a single daily dose) in 24 hours.275

Do not exceed maximum recommended dosage.279 Additional doses not recommended within 24 hours, even if no bowel movement occurs after a dose.279 (See Chronic Use or Overdosage under Cautions.)

Bowel Cleansing
Sodium Phosphates Enemas
Rectal

For self-medication: Maximum 7 g of dibasic sodium phosphate and 19 g of monobasic sodium phosphate (1 bottle of Fleet Enema [approximately 118 mL] or Fleet Enema Extra [approximately 197 mL]) in 24 hours.219 228

OsmoPrep Sodium Phosphates Tablets
Oral

Do not repeat sodium phosphates tablet regimen for bowel cleansing within 7 days of previous administration.213

Special Populations

Hepatic Impairment

No specific dosage recommendations at this time.212 213

Renal Impairment

Magnesium laxatives not for self-medication in patients with renal disease.215 216 217 218 222 223 225 232 (See Contraindications under Cautions.)

Sodium phosphates not for use in patients with clinically important renal function impairment.219 220 (See Contraindications and also Renal Effects under Cautions.)

Geriatric Patients

Caution advised, but no specific dosage recommendations; consider possible age-related decrease in renal and/or cardiac function and concomitant disease and drug therapy.212 213 221 (See Geriatric Use under Cautions.)

Cautions for Saline Laxatives

Contraindications

Warnings/Precautions

Warnings

Renal Effects

Renal failure, acute phosphate nephropathy, and nephrocalcinosis reported rarely with oral sodium phosphates preparations (i.e., oral solution, OsmoPrep tablets) used for bowel cleansing;212 213 220 221 236 238 239 283 b onset of kidney injury occurred from several days to several months after use.239 283 Often resulted in permanent renal function impairment and sometimes required long-term dialysis.212 213

Risk of acute phosphate nephropathy may be increased in patients with increased age (>55 years of age), hypovolemia, increased bowel transit time (e.g., bowel obstruction), active colitis, baseline renal disease, or known or suspected electrolyte disturbances (e.g., dehydration),220 and in patients receiving drugs that affect renal perfusion or function (e.g., diuretics, ACE inhibitors, angiotensin II receptor antagonists, possibly NSAIAs).212 213 220 239 240 283 (See Specific Drugs under Interactions.) However, acute phosphate nephropathy also reported in patients without identifiable risk factors, although possibility of dehydration before or insufficient fluid intake after ingestion of oral sodium phosphates preparations cannot be ruled out.239

Obtain baseline and postcolonoscopy laboratory measurements.212 213 (See Adequate Patient Monitoring under Cautions.)Use oral sodium phosphates preparations with caution in patients with dehydration, impaired renal function (Clcr <30 mL/minute), or history of acute phosphate nephropathy.212 213 239 283

Because acute phosphate nephropathy also reported with OTC preparations, FDA recommends using these preparations for bowel cleansing only when a prescription for such use has been issued.239 240 In February 2011, after reviewing additional cases of acute kidney injury associated with oral sodium phosphates (some resulting in kidney transplantation, dialysis, long-term renal failure, and, rarely, death), FDA issued a proposed rule to classify sodium phosphate salts as not generally recognized as safe (GRAS) for bowel cleansing.282 FDA also suggested removal of the professional labeling for sodium phosphates (which discusses use of the drugs as part of a bowel cleansing regimen) from the OTC monograph for laxative drug products.282

Health-care professionals should cease recommending OTC oral sodium phosphates preparations for bowel cleansing and should have removed these preparations from pharmacy shelves.x y Advise patients requesting an OTC oral sodium phosphates preparation for bowel cleansing to consult their clinician for an alternative bowel cleansing preparation (i.e., one available by prescription only).y OTC oral sodium phosphates preparations will continue to be available for use as laxatives (i.e., for relief of constipation).239 240

Electrolyte Abnormalities

Possible electrolyte abnormalities (e.g., hyperphosphatemia, hypernatremia, hypocalcemia, hypokalemia) with sodium phosphates preparations.212 213 219 220 227 228 b May result in metabolic acidosis, renal failure, tetany, cardiac arrhythmias, prolongation of the QT interval, generalized tonic-clonic seizures, and/or loss of consciousness.212 213 (See Renal Effectsand also Seizures and also Cardiac Effects under Cautions.)

Fatalities secondary to substantial fluid shifts, severe electrolyte abnormalities, and cardiac arrhythmias reported in patients with renal insufficiency, bowel perforation, or who have misused or overused sodium phosphates preparations.212 213 219

Increased risk of electrolyte disturbances in patients with dehydration,220 221 inability to take oral fluid,220 221 gastric retention,212 213 220 221 or colitis;220 221 patients taking concomitant drugs that may affect electrolyte concentrations;212 213 219 220 and geriatric patients.220 221

Obtain baseline and postcolonoscopy laboratory measurements.212 213 (See Adequate Patient Monitoring under Cautions.)

Use sodium phosphates preparations with caution in patients with known or suspected electrolyte disturbances (e.g., dehydration).212 213 227 228 Maintain adequate hydration before, during, and after the use of such products.212 213 219 (See Fluid Intake under Cautions.)

Correct electrolyte abnormalities (e.g., hypernatremia, hyperphosphatemia, hypokalemia, hypocalcemia) immediately with appropriate electrolyte and fluid replacement.212 219 220 221

Patients with electrolyte abnormalities such as hypernatremia, hyperphosphatemia, hypokalemia, or hypocalcemia should have their electrolytes corrected before treatment with OsmoPrep Tablets.

Sensitivity Reactions

Hypersensitivity Reactions

Hypersensitivity reactions, including anaphylaxis, rash, pruritus, urticaria, throat tightness, bronchospasm, dyspnea, pharyngeal edema, dysphagia, paresthesia, swelling of the lips and tongue, and facial swelling reported.283

Other Warnings and Precautions

Chronic Use or Overdosage

Laxative dependence, chronic constipation, and loss of normal bowel function may occur during long-term use.222 223 232 b

Serious, potentially life-threatening electrolyte disturbances, dehydration, and hypovolemia may occur.212 219 220 221 b (See Electrolyte Abnormalities under Cautions.)

Severe dehydration, electrolyte abnormalities (e.g., hypernatremia, hyperphosphatemia, hypocalcemia), acute kidney injury, cardiac arrhythmias, and/or death reported rarely following use of OTC sodium phosphates preparations (i.e., oral solution, enema) for self-medication of occasional constipation.279 The majority of reported adverse events occurred in patients who received higher than recommended dosages in a 24-hour period (i.e., a single dose that was larger than recommended or >1 dose in a day) or in patients at increased risk of developing sodium phosphate-induced toxicity.279 Do not exceed maximum recommended dosage.279 (See Prescribing Limits under Dosage and Administration.)

FDA states clinicians should use caution when recommending use of OTC sodium phosphates preparations in patients >55 years of age; patients with hypovolemia, kidney disease, decreased intravascular volume, or decreased bowel transit time; and patients receiving drugs that affect renal perfusion or function (e.g., diuretics, ACE inhibitors, angiotensin II receptor antagonists, NSAIAs).279 (See Contraindications under Cautions and also see Interactions.)

Assess serum electrolytes and renal function in patients who may be at increased risk of developing adverse effects, including those who have retained a rectal dose for >30 minutes, who are vomiting, or who may have signs of dehydration.279

Adequate Patient Monitoring

For bowel cleansing, obtain baseline and postprocedural (e.g., postcolonoscopy) laboratory measurements, including serum concentrations of electrolytes (i.e., potassium, sodium), phosphate, calcium, creatinine, and BUN in patients at increased risk for adverse events (e.g., history of renal insufficiency, history of or at greater risk of acute phosphate nephropathy, known or suspected electrolyte disorders, seizures, arrhythmias, cardiomyopathy, prolonged QT interval, recent MI, known or suspected hyperphosphatemia, hypocalcemia, hypokalemia, hypernatremia,212 213 dehydration,220 221 inability to take oral fluid,220 221 taking concomitant drugs that may affect electrolyte levels,212 213 219 220 gastric retention,212 213 220 221 colitis,220 221 elderly).220 221 Monitor GFR in smaller, frail patients.239

If vomiting and/or signs of dehydration occur, obtain postcolonoscopy laboratory measurements (phosphate, calcium, potassium, sodium, creatinine, BUN).212 213

Cardiac Effects

Prolonged QT interval and arrhythmias reported with sodium phosphates preparations; associated with severe electrolyte imbalance (e.g., hypokalemia, hypocalcemia).212 213 220 (See Electrolyte Abnormalities under Cautions.)

Use sodium phosphates with caution in patients with an increased risk of arrhythmias (i.e., history of cardiomyopathy, prolonged QT interval, a history of uncontrolled arrhythmias, recent MI, concomitant use of drugs known to prolong QT interval).212 213 (See Drugs Affecting QT Interval under Interactions.) Obtain baseline and postcolonoscopy laboratory measurements, including ECGs, in such patients.212 213 (See Adequate Patient Monitoring under Cautions.)

Use sodium phosphates with caution in patients with CHF,212 213 220 221 ascites,212 213 acute MI,220 221 unstable angina,212 213 220 221 and recent cardiac surgery (including CABG).212 Some manufacturers state that sodium phosphates preparations are contraindicated in patients with CHF 219 220 221 227 228 229 230 or ascites.219 220 221 227 228

CHF has occurred with indiscriminate use of sodium-containing saline laxatives.b

Seizures

Rarely, generalized tonic-clonic seizures and/or loss of consciousness reported with sodium phosphates preparations; associated with electrolyte abnormalities and low serum osmolality.212 213 (See Electrolyte Abnormalities under Cautions.) Resolved with correction of fluid and electrolyte abnormalities.212 213

Use sodium phosphates with caution in patients with history of seizures or at higher risk of seizures (e.g., known or suspected hyponatremia, withdrawing from alcohol or benzodiazepines, concomitant use of drugs that lower the seizure threshold).212 213 (See Specific Drugs under Interactions.) Obtain baseline and postcolonoscopy laboratory measurements in such patients.212 213 (See Adequate Patient Monitoring under Cautions.)

GI Effects

Use oral sodium phosphates preparations with caution in patients with gastric retention,212 213 pseudo-obstruction of the bowel,212 213 severe chronic constipation,212 213 delayed bowel emptying,239 severe active ulcerative colitis,283 colostomy or ileostomy,219 220 221 or hypomotility syndrome.212 213 Obtain baseline and postcolonoscopy laboratory measurements in such patients.212 213 220 221 (See Adequate Patient Monitoring and also Contraindications under Cautions.)

Sodium phosphates preparations may induce colonic mucosal aphthous ulceration; consider in patients with known or suspected inflammatory bowel disease.212 213

Possible increased sodium phosphate absorption during an acute exacerbation of chronic inflammatory bowel disease; use with caution.212 213 Some manufacturers state that sodium phosphates preparations are contraindicated in patients with active inflammatory bowel disease.220 221

Use of Fixed Combinations

When magnesium hydroxide is used in fixed combination with mineral oil, consider the cautions, precautions, and contraindications associated with mineral oil.218

When magnesium citrate or sodium phosphates is used in regimens with bisacodyl, consider the cautions, precautions, and contraindications associated with bisacodyl.221 222 223 229 230

Fluid Intake

Inadequate fluid intake may lead to excessive fluid loss, hypovolemia, and dehydration;212 213 220 221 may be associated with acute renal failure.220 (See Renal Effects under Cautions.)

Obtain baseline and postcolonoscopy laboratory measurements in dehydrated patients or those unable to take oral fluids.220 221 (See Adequate Patient Monitoring under Cautions.)

Dehydration from purgation exacerbated by inadequate oral fluid intake,212 213 220 221 nausea,220 vomiting,212 213 220 and/or use of diuretics or other drugs.212 213 220 221 (See Specific Drugs under Interactions.)

Patients must have adequate fluid intake before, during, and after bowel cleansing regimens.212 213 220 221

Assess hydration status in patients at risk for dehydration prior to use of purgatives.220 221

Swallowing Difficulties

Undigested or partially digested tablets of sodium phosphates or other drugs may be seen in stool or during colonoscopy in patients with swallowing difficulties, anatomic narrowing of the esophagus, or stricture.212

Dietary Considerations

Magnesium laxatives not for self-medication in patients on a magnesium-restricted diet.215 216 217 218 225

Carbon dioxide-releasing suppositories not for self-medication in patients on a low-salt diet.214 231

Use sodium phosphates preparations with caution in patients on a low-salt diet.220

Electrolytic Content

CEO-TWO suppositories contain 164 mg (7.13 mEq) of sodium per suppository.231

Each level teaspoonful of magnesium sulfate crystals contains approximately 5 g of magnesium sulfate and 495 mg (40.7 mEq) of magnesium.225

Magnesium citrate oral solution contains 0.33 mg of sodium and 3.85–4.71 mEq of magnesium per 5 mL.224 a

Magnesium hydroxide contains about 34.3 mEq of magnesium per g of the drug; milk of magnesia (regular strength [400 mg/5 mL]) contains approximately 2.4–2.9 mEq of magnesium per g or 13.66 mEq of magnesium per 5 mL.a

Fleet Enema and Fleet Pedia-Lax Enema contain 37 mg (1.61 mEq) of sodium per mL and 4.15 mEq of phosphate per mL (total sodium content: 4.4 g in 118 mL and 2.2 g in 59 mL, respectively).219 Fleet Enema Extra contains 22 mg of sodium per mL (total sodium content: 4.4 g in 197 mL).228

Sodium Phosphate Oral Solutions contains 556 mg (24.1 mEq) of sodium per 5 mL.275

OsmoPrep tablets contain 0.398 g of dibasic sodium phosphate and 1.102 g of monobasic sodium phosphate per tablet.212 213

Specific Populations

Pregnancy

Magnesium sulfate: Category B.c

Sodium phosphates: Category C.212 213

Lactation

Magnesium sulfate may be distributed into milk in small amounts.a c

The AAP classifies magnesium sulfate as compatible with breast-feeding.c

Pediatric Use

Avoid use of laxatives in infants and children; counsel parents on acceptable variations in frequency of bowel movements.b

Magnesium citrate preparations for bowel cleansing: Use in children <12 years of age only as directed by clinician.222 223 232

Magnesium citrate for laxative use: Use in children <2 years of age only as directed by clinician.224 234

Magnesium hydroxide: Not for self-medication in children <2 years of age.217 233 235

Fixed combination of magnesium hydroxide and mineral oil: Not for self-medication in children <6 years of age.218

Oral magnesium sulfate preparations: Not for self-medication in children <6 years of age.225

Oral sodium phosphates preparations for bowel cleansing: Safety and efficacy not established in children <18 years of age;212 213 220 avoid use in such children.239

Oral sodium phosphates preparations for laxative use: Not for self-medication in children <5 years of age.275 Clinicians should be cautious in recommending use of these preparations in children ≤5 years of age.279

Rectal sodium phosphates enemas: Safety and efficacy not established in children <2 years of age;219 avoid use in such children.227 275 279

Carbon-dioxide releasing suppositories: Use in children <12 years of age only as directed by clinician.214

Geriatric Use

Sodium phosphates preparations: Safety and efficacy in those ≥65 years of age similar to younger adults; manufacturers state that sodium phosphates should be used with caution in such patients due to greater frequency of decreased renal and/or cardiac function and of concomitant disease and drug therapy observed in the elderly.212 213 220 221 (See Special Populations under Pharmacokinetics.) FDA recommends caution when using oral sodium phosphates preparations as bowel cleansing regimens in patients >55 years of age due to increased risk of acute phosphate nephropathy.239 (See Renal Effects under Cautions.)

Severe and potentially fatal cases of electrolyte disorders possible; consider risk/benefit.220 221 Consider baseline and postcolonoscopy laboratory measurements.212 213 220 221 (See Electrolyte Abnormalities and also see Adequate Patient Monitoring under Cautions.)

Hepatic Impairment

Sodium phosphates tablets: Not studied in patients with hepatic impairment.212 213

Restrict use of sodium-containing saline laxatives in patients with cirrhosis.b

Avoid use of sodium phosphates preparations in patients with ascites.219 220 221 227 228 229 230

Renal Impairment

Sodium phosphates preparations: Use with caution in renal impairment.212 213 227 228 Manufacturer of OsmoPrep states that this preparation should be used with extreme caution in patients with severe renal impairment (Clcr <30 mL/minute);212 213 however, other manufacturers state use is contraindicated in patients with clinically important renal impairment.219 220 221 Obtain baseline and postcolonoscopy laboratory measurements.212 213 (See Renal Effects and also see Adequate Patient Monitoring under Cautions.)

Death secondary to substantial fluid shifts, severe electrolyte abnormalities, and cardiac arrhythmias reported in patients with renal impairment.b

Magnesium laxatives not for self-medication in patients with renal disease.215 216 217 218 222 223 225 232

Possible accumulation of magnesium, potassium, or sodium in patients with renal disease; use laxative products containing >50 mEq of magnesium, 25 mEq of potassium, or 1 mEq of sodium per dose only under supervision of a clinician and monitor electrolytes.b (See Electrolytic Content under Cautions.)

Common Adverse Effects

Sodium phosphates preparations: Dehydration, abdominal pain, bloating, nausea, vomiting, headache, dizziness,212 213 b hyperphosphatemia, hypocalcemia, hypokalemia.212

Carbon dioxide-releasing suppositories: Rectal discomfort, burning sensation.b

Magnesium citrate: Abdominal discomfort, faintness, rectal burning, mild cramps.222 223

Drug Interactions

GI Drug Absorption

By increasing intestinal motility, can potentially decrease transit time of concomitantly administered oral drugs and decrease their absorption.212 213 220 b

Administer magnesium sulfate ≥2 hours before or after other drugs.225

Drugs Affecting QT Interval

Risk of prolonged QT interval and potentially serious or life-threatening arrhythmias.213 Use sodium phosphates preparations with caution in combination with drugs that prolong the QT interval.213 220 (See Cardiac Effects under Cautions.)

Drugs Affecting Renal Perfusion or Function

Increased risk of acute phosphate nephropathy (nephrocalcinosis) when used concomitantly with sodium phosphates preparations.213 (See Renal Effects under Cautions.)

Drugs Affecting Electrolyte Levels

Increased risk of electrolyte abnormalities (e.g., hypernatremia, hyperphosphatemia, hypokalemia, hypocalcemia) when used concomitantly with sodium phosphates preparations.213 220 Avoid concomitant use with other laxatives containing sodium phosphate.279

Drugs Affecting Seizure Threshold

Possible increased risk of seizure when used concomitantly with sodium phosphates preparations.213

Specific Drugs

Drug

Interaction

Comments

Alcohol

Possible increased risk of seizures for patients withdrawing from alcohol212 213

Use caution when administering sodium phosphates preparations concomitantly during alcohol withdrawal212 213

ACE inhibitors

Increased risk of dehydration,220 hypovolemia, or acute phosphate nephropathy212 213

Use concomitantly with caution239

Angiotensin II receptor antagonists

Increased risk of dehydration,220 hypovolemia,220 and acute phosphate nephropathy212 213

Use concomitantly with caution239

Antibiotics

Possible delayed or decreased absorption from the GI tract220

Efficacy may be reduced or absent220

Anticonvulsants

Possible delayed or decreased absorption from the GI tract220

Efficacy may be reduced or absent220

Antidiabetic agents

Possible delayed or decreased absorption from the GI tract220

Efficacy may be reduced or absent220

Benzodiazepines

Possible increased risk of seizures for patients withdrawing from benzodiazepines212 213

Use caution when administering sodium phosphates preparations concomitantly during benzodiazepine withdrawal213

Diuretics

Increased risk of dehydration220 and acute phosphate nephropathy212 213

Correct electrolyte balances before treating with sodium phosphates preparations213

Administer concomitantly with caution219 220 227 228

Laxatives or purgative agents

Possible additive effects

Do not use sodium phosphates preparations with additional laxatives or purgative agents213

Lithium

Increased risk of dehydration,220 hypovolemia,220 and electrolyte abnormalities212 213

NSAIAs

Increased risk of dehydration,220 hypovolemia,220 and acute phosphate nephropathy212 213

Use concomitantly with caution220 239

Oral contraceptives

Delayed or decreased absorption from the GI tract possible220

Efficacy may be reduced or absent220

Stool softener laxatives (e.g., docusate)

Increased rate of mineral oil absorptionb

Do not use fixed combination containing magnesium hydroxide and mineral oil concurrently with docusate218

Tricyclic antidepressants (TCAs)

Possible increased risk of seizures212 213

Use caution when administered concomitantly with sodium phosphates preparations212 213

Saline Laxatives Pharmacokinetics

Absorption

Bioavailability

Oral magnesium-containing laxatives: 15–30% may be absorbed.a

Oral phosphate laxatives: Extent of phosphate and sodium absorption unknown.a

Rectal phosphate enemas: Extent of phosphate absorption unknown; reportedly 1–20% of sodium and phosphate absorbed.a

Onset

Bowel movement usually occurs within 0.5–6 hours following oral administration of magnesium- or phosphate-containing laxatives.215 216 217 218 220 223 224 225 232

Bowel movement usually occurs within 5–30 minutes following rectal administration of carbon dioxide-releasing suppositories.231

Bowel movement usually occurs within 1–5 minutes following administration of phosphate-containing rectal enemas.219 227 228

Duration

Purgative effects of sodium phosphates tablets (OsmoPrep) persist for 1–3 hours.212 213

Distribution

Extent

Magnesium is distributed into saliva and milk in small amounts.a

Elimination

Elimination Route

Magnesium and phosphate are excreted principally by the kidneys.a

Special Populations

Pharmacokinetics of sodium phosphates tablets not evaluated in patients with renal impairment; however, patients with renal disease may have difficulty excreting a large phosphate load.213

In geriatric patients >70 years of age, plasma half-life of oral sodium phosphates tablets increased twofold.212 213

Stability

Storage

Oral

Solutions

Magnesium citrate: 2–30°C;222 223 224 protect from excessive heat224 and freezing.222 224 Discard within 24 hours of opening.224

Sodium phosphates: May refrigerate; do not freeze.220

Suspensions

Magnesium hydroxide: Room temperature; avoid freezing.215 216 233 Keep tightly closed.215 216 233

Fixed-combination magnesium hydroxide and mineral oil: Room temperature; avoid freezing.218 Keep tightly closed.218

Tablets

Sodium phosphates: 25°C (may be exposed to 15–30°C).212 213

Tablets, Chewable

Magnesium hydroxide: Room temperature.217

Rectal

Suppositories

CEO-TWO suppositories: 20–25°C (do not exceed 30°C).231 Do not refrigerate.214 231

Actions

Advice to Patients

Preparations

Excipients in commercially available drug preparations may have clinically important effects in some individuals; consult specific product labeling for details.

Please refer to the ASHP Drug Shortages Resource Center for information on shortages of one or more of these preparations.

* available from one or more manufacturer, distributor, and/or repackager by generic (nonproprietary) name

Magnesium Citrate (Citrate of Magnesia)

Routes

Dosage Forms

Strengths

Brand Names

Manufacturer

Bulk

Powder

Oral

Solution

291 mg/5 mL

Magnesium Citrate Oral Solution

* available from one or more manufacturer, distributor, and/or repackager by generic (nonproprietary) name

Magnesium Hydroxide

Routes

Dosage Forms

Strengths

Brand Names

Manufacturer

Bulk

Powder

Oral

Suspension

400 mg/5 mL*

Milk of Magnesia

Phillips’ Milk of Magnesia

Bayer

800 mg/5 mL

Little Phillips’ Milk of Magnesia

Bayer

Phillips’ Concentrated Milk of Magnesia

Bayer

1.2 g/5 mL*

Milk of Magnesia Concentrate

Tablets, chewable

311 mg

Phillips’ Chewable Tablets

Bayer

400 mg

Fleet Pedia-Lax Chewable Tablets

Fleet

* available from one or more manufacturer, distributor, and/or repackager by generic (nonproprietary) name

Magnesium Hydroxide Combinations (combination)

Routes

Dosage Forms

Strengths

Brand Names

Manufacturer

Oral

Suspension

300 mg (magnesium hydroxide)/5 mL with Mineral Oil 1.25 mL/5 mL*

Phillips’ M-O(combination)

Bayer

* available from one or more manufacturer, distributor, and/or repackager by generic (nonproprietary) name

Magnesium Sulfate (Epsom Salt)

Routes

Dosage Forms

Strengths

Brand Names

Manufacturer

Bulk

Crystal*

Bulk

Powder*

* available from one or more manufacturer, distributor, and/or repackager by generic (nonproprietary) name

Sodium Phosphate, Dibasic

Routes

Dosage Forms

Strengths

Brand Names

Manufacturer

Bulk

Powder*

* available from one or more manufacturer, distributor, and/or repackager by generic (nonproprietary) name

Sodium Phosphate, Monobasic

Routes

Dosage Forms

Strengths

Brand Names

Manufacturer

Bulk

Powder*

Carbon Dioxide-releasing Suppositories

Routes

Dosage Forms

Strengths

Brand Names

Manufacturer

Rectal

Suppository

Potassium Bitartrate 0.9 g and Sodium Bicarbonate 0.6 g

Ceo-Two

Beutlich

* available from one or more manufacturer, distributor, and/or repackager by generic (nonproprietary) name

Sodium Phosphates

Routes

Dosage Forms

Strengths

Brand Names

Manufacturer

Oral

Solution

Dibasic Sodium Phosphate 900 mg/5 mL with Monobasic Sodium Phosphate 2.4 g/5 mL*

Sodium Phosphate Oral Saline Laxative

Tablet

Dibasic Sodium Phosphate (anhydrous) 0.398 g with Monobasic Sodium Phosphate (monohydrate) 1.102 g

OsmoPrep

Salix

Rectal

Solution

Dibasic Sodium Phosphate 36 mg/mL with Monobasic Sodium Phosphate 96 mg/mL

Fleet Enema Extra

Fleet

Dibasic Sodium Phosphate 59 mg/mL with Monobasic Sodium Phosphate 161 mg/mL

Fleet Enema

Fleet

Fleet Pedia-Lax Enema

Fleet

AHFS DI Essentials™. © Copyright 2024, Selected Revisions October 1, 2014. American Society of Health-System Pharmacists, Inc., 4500 East-West Highway, Suite 900, Bethesda, Maryland 20814.

† Off-label: Use is not currently included in the labeling approved by the US Food and Drug Administration.

References

Only references cited for selected revisions after 1984 are available electronically.

212. Salix Pharmaceuticals Inc. Visicol (sodium phosphate monobasic monohydrate, USP, and sodium phosphate dibasic anhydrous, USP) tablets prescribing information. Morrisville, NC; 2008 Jun.

213. Salix Pharmaceuticals Inc. OsmoPrep (sodium phosphate monobasic monohydrate, USP, and sodium phosphate dibasic anhydrous, USP) tablets prescribing information. Morrisville, NC; 2008 Jul.

214. Beutlich LP Pharmaceuticals. CEO-TWO evacuant (laxative adult rectal suppository) product information. In: Physicians' desk reference for nonprescription drugs and dietary supplements. 25th ed. Montvale, NJ: Thomson PDR; 2004:624.

215. Bayer Consumer Care. Phillips' milk of magnesia (magnesium hydroxide saline laxative) patient information. Morristown, NJ. From website. Accessed 2009 Feb 17. http://www.phillipsrelief.com

216. Bayer Consumer Care. Concentrated Phillips' milk of magnesia (magnesium hydroxide saline laxative) patient information. Morristown, NJ. From website. Accessed 2009 Feb 17. http://www.phillipsrelief.com

217. Bayer Consumer Care. Phillips'chewable tablets (saline laxative/antacid) patient information. Morristown, NJ. From website. Accessed 2009 Feb 17. http://www.phillipsrelief.com

218. Bayer Consumer Care. Phillips'M-O (saline laxative/lubricant laxative) patient information. Morristown, NJ. From website. Accessed 2009 Feb 17. http://www.phillipsrelief.com

219. CB Fleet Co. Fleet enema (saline laxative) prescribing information. In: PDR.net [database online]. Montvale, NJ: Thomson Healthcare; 2007. Updated 2006.

220. CB Fleet Co. Fleet Phospho-soda (oral saline laxative) prescribing information. In: PDR.net [database online]. Montvale, NJ: Thomson Healthcare; 2007. Updated 2006.

221. CB Fleet Co. Fleet prep kits prescribing information. In: PDR.net [database online]. Montvale, NJ: Thomson Healthcare; 2007. Updated 2006.

222. Lafayette Pharmaceuticals Inc. Tridrate (magnesium citrate oral solution USP, bisacodyl tablets USP, bisacodyl suppository USP) bowel evacuant kit prescribing information. Lafayette, IN; 1992 Nov.

223. E-Z-EM, Inc. Liquid LoSo Prep (magnesium citrate oral solution USP, bisacodyl tablets [enteric coated] USP, bisacodyl suppository USP) bowel cleansing system patient information. Westbury, NY; 2004 Oct.

224. Rite Aid. Magnesium citrate oral solution patient information. From website. Accessed 2007 Sept 12. http://www.drugstore.com

225. Vi-Jon. Epsom salt (magnesium sulfate USP) patient information. Smyrna, TN. Undated.

226. Lafayette Pharmaceuticals Inc. Tridrate (magnesium citrate oral solution, bisacodyl tablets, bisacodyl suppository) Dry Bowel Cleansing System patient information. Lafayette, IN. Undated.

227. CB Fleet Company, Inc. Fleet Pedia-Lax Enema (saline laxative/bowel cleanser) patient information. Lynchburg, VA. 2007. From website. Accessed 2009 Feb 19. http://www.pedia-lax.com

228. CB Fleet Company, Inc. Fleet Enema Extra (saline laxative/bowel cleanser) patient information. Lynchburg, VA. 2007. From website. Accessed 2009 Feb 19. http://www.phosphosoda.com

229. CB Fleet Company, Inc. Fleet Prep Kit #1 patient information. Lynchburg, VA. Undated.

230. CB Fleet Company, Inc. Fleet Prep Kit #3 patient information. Lynchburg, VA. Undated.

231. Beutlich Pharmaceuticals LP. CEO-TWO laxative suppositories patient information. Waukegan, IL. From website. Accessed 2009 Feb 19. http://www.beutlich.com

232. E-Z-EM, Inc. LoSo Prep (magnesium carbonate, citric acid, and potassium citrate for oral solution, bisacodyl tablets [enteric coated] USP, bisacodyl suppository USP) bowel cleansing system patient information. Westbury, NY; 2004 Feb.

233. Bayer Consumer Care. Little Phillips' milk of magnesia (magnesium hydroxide saline laxative) patient information. Morristown, NJ. From website. Accessed 2009 Jan 17. http://www.phillipsrelief.com

234. Food and Drug Administration. Laxative drug products for over-the-counter human use. 21 CFR Part 334. Fed Regist. 1985; 50:2151-8.

235. CB Fleet Company, Inc. Fleet Pedia-Lax (oral saline laxative) chewable tablets patient information. From website. Accessed 2009 Feb 12. http://www.pedia-lax.com

236. Food and Drug Administration. Healthcare professional sheet: Oral sodium phosphate (OSP) products for bowel cleansing. Available from website. Accessed 2006 Dec 7. http://www.fda.gov/Drugs/DrugSafety/PostmarketDrugSafetyInformationforPatientsandProviders/ucm126084.htm

237. Food and Drug Administration. Food and Drug Administration science backgrounder: Safety of sodium phosphates oral solution. Available from website. Accessed 2006 Dec 7. http://www.fda.gov/Drugs/DrugSafety/PostmarketDrugSafetyInformationforPatientsandProviders/ucm173897.htm

238. Food and Drug Administration. Food and Drug Administration science background paper: Acute phosphate nephropathy and renal failure associated with the use of oral sodium phosphate bowel cleansing products. Available from website. Accessed 2006 Dec 7. http://www.fda.gov/Drugs/DrugSafety/PostmarketDrugSafetyInformationforPatientsandProviders/ucm161581.htm

239. Food and Drug Administration. Information for healthcare professionals: Oral sodium phosphate (OSP) products for bowel cleansing (marketed as Visicol and OsmoPrep, and oral sodium phosphate products available without a prescription). Available from wesbite. 2008 Dec 11. http://www.fda.gov/Drugs/DrugSafety/PostmarketDrugSafetyInformationforPatientsandProviders/ucm126084.htm

240. Food and Drug Administration. Oral sodium phosphate (OSP) actions: Questions and answers. Available from website. Accessed 2008 Dec 11. http://www.fda.gov/Drugs/DrugSafety/PostmarketDrugSafetyInformationforPatientsandProviders/ucm103383.htm

275. CVS. Phosphate oral saline laxative (dibasic sodium phosphate and monobasic sodium phosphate) patient information. From CVS website. Accessed 2014 Apr 24. http://www.cvs.com/shop/product-detail/CVS-Phosphate-Oral-Saline-Laxative-Ginger-Lemon-Flavor?skuId=702298

276. Fleet Laboratories. Questions and answers. From Fleet Laboratories website. Accessed 2014 Apr 24. http://www.fleetlabs.com

277. McNamara S. Dear healthcare provider letter: Decision to discontinue sale of Fleet Prep Kit 1. Lynchburg, VA: Fleet Laboratories. From Fleet Laboratories website. Accessed 2014 Apr 24. http://www.fleetlabs.com

278. McNamara S. Dear healthcare provider letter: Decision to discontinue sale of Fleet Prep Kit 3. Lynchburg, VA: Fleet Laboratories. From Fleet Laboratories website. Accessed 2014 Apr 24. http://www.fleetlabs.com

279. US Food and Drug Administration. FDA Drug Safety Communication: FDA warns of possible harm from exceeding recommended dose of over-the-counter sodium phosphate products to treat constipation. Rockville, MD; 2014 Jan 8. From FDA website. Accessed 2014 May 12. http://www.fda.gov/Drugs/DrugSafety/ucm380757.htm

280. CB Fleet Company, Inc. Fleet Enema saline laxative patient information. Lynchburg, VA. From website. Accessed 2014 Apr 30. http://www.fleetlabs.com

281. CB Fleet Company, Inc. Fleet Enema, Fleet Enema Extra, Fleet Pedia-Lax Enema, and Fleet Enema for Children prescribing information. In: PDR for Nonprescription Drugs, Dietary Supplements, and Herbs. Montvale, NJ: Medical Economics Company Inc; 2011.

282. US Food and Drug Administration. Professional Labeling for Laxative Drug Products for Over-the-Counter Human Use; Proposed Amendment to the Tentative Final Monograph. 21 CFR Parts 310 and 334. Proposed Rule. [Docket No. FDA-1978-N-0021]. Fed Regist. 1979; 76:7743-57.

283. Salix Pharmaceuticals, Inc. OsmoPrep (sodium phosphate monobasic monohydrate, USP, and sodium phosphate dibasic anhydrous, USP) tablets prescribing information. Raleigh, NC; 2012 Oct.

a. AHFS drug information 2009. McEvoy GK, ed. Saline laxatives. Bethesda, MD: American Society of Health-System Pharmacists; 2009:2986-8.

b. AHFS drug information 2009. McEvoy GK, ed. Cathartics and laxatives general statement. Bethesda, MD: American Society of Health-System Pharmacists; 2009:2976-80.

c. Briggs GG, Freeman RK, Yaffe SJ. Drugs in pregnancy and lactation. 7th ed. Philadelphia, PA: Lippincott Williams & Wilkins; 2005:957-961.

x. McNamara S. Dear healthcare professional letter regarding important prescribing and safety information. Lynchburg, VA; 2008 Dec 15.

y. McNamara S. Dear pharmacist letter regarding important safety information and notice of recalled products. Lynchburg, VA; 2008 Dec 15.