Drug class: Parasympathomimetic (Cholinergic) Agents

Medically reviewed by Drugs.com on Jun 10, 2024. Written by ASHP.

Introduction

Cholinergic agonist.¹⁰¹

Uses for Bethanechol Chloride

Urinary Retention

Treatment of acute postoperative and postpartum nonobstructive urinary retention and neurogenic atony of the bladder with retention.¹⁰¹

Heartburn

Has been shown to produce symptomatic improvement and decrease antacid use in some patients with chronic refractory heartburn^{† [off-label]} and gastroesophageal reflux disease (GERD), including vagotomized and antrectomized patients.^a However, use has decreased because of adverse CNS effects; acid suppression therapy with other agents (e.g., proton-pump inhibitors, histamine H₂-receptor antagonists) is principally used.¹⁰⁵

Bethanechol Chloride Dosage and Administration

Administration

Administer orally on an empty stomach (e.g., 1 hour before or 2 hours after a meal) to minimize nausea and vomiting. ^a

Extemporaneously Compounded Oral Liquid

An extemporaneously compounded oral liquid formulation of bethanechol chloride 5 mg/mL has been prepared using the commercially available tablets and various commercially available vehicles.¹⁰⁶

Standardize 4 Safety

Standardized concentrations for an extemporaneously prepared oral liquid formulation of bethanechol have been established through Standardize 4 Safety (S4S), a national patient safety initiative to reduce medication errors, especially during transitions of care.²⁵² Because recommendations from the S4S panels may differ from the manufacturer’s prescribing information, caution is advised when using concentrations that differ from labeling, particularly when using rate information from the label.²⁵² For additional information on S4S (including updates that may be available), see [Web]²⁵² .

Dosage

Available as bethanechol chloride; dosage expressed in terms of the salt.¹⁰¹

Individualize dosage according to the type and severity of the condition.¹⁰¹

Adults

Urinary Retention

Oral

Determine the minimum effective dosage by administering 5 or 10 mg every hour until a satisfactory response occurs or a maximum of 50 mg has been given.¹⁰¹

Usual dosage: 10–50 mg 3–4 times daily.¹⁰¹

Heartburn† [off-label]

Oral

25 mg 4 times daily has been given.^a

Special Populations

No special population dosage recommendations at this time.¹⁰¹

Cautions for Bethanechol Chloride

Contraindications

• Hyperthyroidism.¹⁰¹

• Peptic ulcer.¹⁰¹

• Latent or active bronchial asthma.¹⁰¹

• Coronary artery disease (CAD).¹⁰¹

• Epilepsy.¹⁰¹

• Parkinsonism. ¹⁰¹

• Pronounced bradycardia or hypotension.¹⁰¹

• Vasomotor instability.¹⁰¹

• Condition in which the strength or integrity of the GI or bladder wall is in question or when increased muscular activity of GI tract or urinary bladder might prove harmful (e.g., recent urinary bladder surgery, GI resection and anastomosis) or when there is possible obstruction of GI tract or bladder neck, spastic GI disturbances, acute inflammatory GI tract lesions, peritonitis, or marked vagotonia.¹⁰¹

• Known hypersensitivity to the drug or any ingredient in the formulation. ¹⁰¹

Warnings/Precautions

General Precautions

Urinary Tract Infections

Risk of infection in patients with urinary retention and bacteriuria; if sphincter fails to relax, bethanechol-induced bladder contraction may force urine up ureter into kidney pelvis, causing reflux infection.¹⁰¹

Cardiovascular Effects

May produce a slight, transient decrease in diastolic BP with mild reflex tachycardia. ^a Patients with hypertension may react with a precipitous fall in BP. ^a

Periods of atrial fibrillation reported in hyperthyroid patients following administration of cholinergic drugs.^a

Specific Populations

Pregnancy

Animal reproduction studies not performed; not known whether the drug can cause fetal harm.¹⁰¹

Use during pregnancy only when clearly needed.¹⁰¹

Lactation

Not known whether bethanechol is distributed into milk.¹⁰¹ Discontinue nursing or the drug.¹⁰¹

Pediatric Use

Safety and efficacy not established.¹⁰¹

Common Adverse Effects

Adverse effects rare after oral administration.¹⁰¹ Adverse effects are most likely to occur when dosage is increased. ^a

Abdominal cramps ^a , colicky pain, ^a flushing, ^a sweating, ^a salivation, ^a malaise, ^a headache, ^a diarrhea, ^a nausea, ^a vomiting, ^a bronchial constriction, ^a urinary urgency, ^a miosis. ^a

Drug Interactions

Specific Drugs and Laboratory Tests

Bethanechol Chloride Pharmacokinetics

Absorption

Bioavailability

Poorly absorbed from the GI tract.^a

Onset

Effects may be evident within 30 minutes after oral administration; usually, 60–90 minutes required to reach maximum effectiveness. ^a

Duration

Usually, 1 hour following oral administration; however, large doses (300–400 mg) have been reported to produce effects for up to 6 hours.¹⁰¹

Distribution

Extent

Does not cross the blood-brain barrier in usual doses.^{101 a} Distribution into other body fluids is largely unknown.^a

Elimination

Metabolic path and mode of excretion not known.^{101 a}

Stability

Storage

Oral

Tablets

Tight containers at 20–25°C (excursions permitted between 15–30°C).¹⁰¹

Actions

• Synthetic ester structurally and pharmacologically related to acetylcholine.¹⁰¹

• Directly stimulates cholinergic receptors; stimulates ganglia to a lesser extent.^{101 a}

• Effects are almost exclusively muscarinic; little, if any, nicotinic activity, and cardiovascular effects are negligible.^{101 a}

• Increases tone and peristaltic activity in the stomach and intestines, increases esophageal peristalsis and the resting pressure of the lower esophageal sphincter, increases pancreatic and GI secretions, contracts detrusor muscle of urinary bladder, decreases bladder capacity, and increases frequency of ureteral peristaltic waves.^{101 a}

Advice to Patients

• Inform patient to take 1 hour before or 2 hours after meals to avoid nausea or vomiting.¹⁰¹

• Risk of dizziness, lightheadedness, or fainting. Use caution when rising from a lying or sitting position.¹⁰¹

• Importance of informing clinicians of existing or contemplated concomitant therapy, including prescription and OTC drugs.¹⁰¹

• Importance of women informing clinicians if they are or plan to become pregnant or plan to breast-feed.¹⁰¹

• Importance of informing patients of other important precautionary information.¹⁰¹

Additional Information

The American Society of Health-System Pharmacists, Inc. represents that the information provided in the accompanying monograph was formulated with a reasonable standard of care, and in conformity with professional standards in the field. Readers are advised that decisions regarding use of drugs are complex medical decisions requiring the independent, informed decision of an appropriate health care professional, and that the information contained in the monograph is provided for informational purposes only. The manufacturer’s labeling should be consulted for more detailed information. The American Society of Health-System Pharmacists, Inc. does not endorse or recommend the use of any drug. The information contained in the monograph is not a substitute for medical care.

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

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