Norfloxacin Dosage

Applies to the following strengths: 400 mg

Usual Adult Dose for:

Cystitis
Urinary Tract Infection
Prostatitis
Gonococcal Infection - Uncomplicated
Pyelonephritis

Additional dosage information:

Renal Dose Adjustments
Liver Dose Adjustments
Precautions
Dialysis
Other Comments

Usual Adult Dose for Cystitis

400 mg orally every 12 hours

Duration of Therapy:

Complicated urinary tract infections (UTIs):10 to 21 days
Uncomplicated UTIs (cystitis) due to Escherichia coli, Klebsiella pneumoniae, or Proteus mirabilis: 3 days
Uncomplicated UTIs due to other listed organisms: 7 to 10 days

Comments:

Since fluoroquinolones (including this drug) have been associated with serious side effects and uncomplicated UTI is self-limiting for some patients, this drug should be saved for treatment of uncomplicated UTIs in patients with no alternative treatment options.

Uses: For the treatment of complicated UTIs due to susceptible strains of Enterococcus faecalis, E coli, K pneumoniae, P mirabilis, Pseudomonas aeruginosa, or Serratia marcescens; for the treatment of uncomplicated UTIs (including cystitis) due to susceptible strains of E faecalis, E coli, K pneumoniae, P mirabilis, P aeruginosa, Staphylococcus epidermidis, S saprophyticus, Citrobacter freundii, Enterobacter aerogenes, E cloacae, P vulgaris, S aureus, or Streptococcus agalactiae

Usual Adult Dose for Urinary Tract Infection

400 mg orally every 12 hours

Duration of Therapy:

Complicated urinary tract infections (UTIs):10 to 21 days
Uncomplicated UTIs (cystitis) due to Escherichia coli, Klebsiella pneumoniae, or Proteus mirabilis: 3 days
Uncomplicated UTIs due to other listed organisms: 7 to 10 days

Comments:

Since fluoroquinolones (including this drug) have been associated with serious side effects and uncomplicated UTI is self-limiting for some patients, this drug should be saved for treatment of uncomplicated UTIs in patients with no alternative treatment options.

Usual Adult Dose for Prostatitis

400 mg orally every 12 hours for 28 days

Use: For the treatment of prostatitis (acute or chronic) due to susceptible strains of E coli

Usual Adult Dose for Gonococcal Infection - Uncomplicated

800 mg orally once

Uses: For the treatment of uncomplicated urethral and cervical gonorrhea due to susceptible strains of Neisseria gonorrhoeae

US CDC recommendations:

Due to high rates of resistance, fluoroquinolones are not recommended for treatment of gonococcal infections in the US; dual therapy with ceftriaxone and azithromycin is the recommended regimen for treatment of gonorrhea in the US.
Antimicrobial susceptibility patterns should be monitored.
The patient's sexual partner(s) should also be evaluated/treated.
Current guidelines should be consulted for additional information.

Usual Adult Dose for Pyelonephritis

Some experts recommend:

Mild infections: 400 mg orally every 12 hours for 14 days

Renal Dose Adjustments

CrCl 30 mL/min/1.73 m2 or less:

For the treatment of UTIs: 400 mg orally once a day
For the treatment of other infections: Data not available

Liver Dose Adjustments

Data not available

Precautions

US BOXED WARNING:
SERIOUS SIDE EFFECTS INCLUDING TENDINITIS, TENDON RUPTURE, PERIPHERAL NEUROPATHY, CNS EFFECTS, AND EXACERBATION OF MYASTHENIA GRAVIS:

Fluoroquinolones (including this drug) have been associated with disabling and potentially irreversible serious side effects that have occurred together (including tendinitis and tendon rupture, peripheral neuropathy, CNS effects). This drug should be discontinued immediately and use of fluoroquinolones (including this drug) should be avoided in patients with any of these serious side effects.
Fluoroquinolones (including this drug) may exacerbate muscle weakness in patients with myasthenia gravis. This drug should be avoided in patients with known history of myasthenia gravis.
Since fluoroquinolones (including this drug) have been associated with serious side effects, this drug should be reserved for use in patients with no alternative treatment options for uncomplicated urinary tract infections (including cystitis).

CONTRAINDICATIONS:

History of hypersensitivity, tendinitis, and/or tendon rupture related to use of this drug or any quinolone antimicrobial agent

Safety and efficacy have not been established in patients younger than 18 years.

Consult WARNINGS section for additional precautions.

Dialysis

Data not available

Other Comments

Administration advice:

Administer at least 1 hour before or at least 2 hours after a meal, milk, and/or other dairy products.
Administer with a glass of water.
Administer this drug at least 2 hours before or 2 hours after iron-, zinc-, aluminum-, or magnesium-containing products (e.g., antacids, sucralfate, mineral supplements/multivitamins, buffered didanosine).

Storage requirements:

Store at 25C (77F); excursions permitted to 15C to 30C (59F to 86F).
Keep bottle tightly closed.

General:

Culture and susceptibility information should be considered when selecting/modifying antibacterial therapy or, if no data are available, local epidemiology and susceptibility patterns may be considered when selecting empiric therapy.
Appropriate culture and susceptibility testing recommended before therapy to isolate and identify infecting organisms and to establish susceptibility to this drug. Therapy may be started before test results are known; appropriate therapy should be continued when results are available.
Production of penicillinase should not affect activity of this drug.

Monitoring:

Hematologic: Organ system functions, including hematopoietic (periodically during prolonged therapy)
Hepatic: Organ system functions, including hepatic (periodically during prolonged therapy)
Infections/Infestations: Culture and susceptibility (periodically during therapy); syphilis serology in gonorrhea patients (at diagnosis and 3 months after therapy)
Renal: Organ system functions, including renal (periodically during prolonged therapy); renal function in elderly patients

Patient advice:

Read the US FDA-approved Medication Guide.
Drink plenty of fluids.
Avoid missing doses and complete the entire course of therapy.
Avoid or minimize exposure to natural or artificial sunlight; use sun protection (e.g., protective clothing, sunscreen) if sun exposure cannot be avoided. Contact physician if sunburn-like reaction or skin eruption develops.
Do not drive, operate machinery, or engage in other tasks that require mental alertness or coordination until you know how the drug affects you.
Stop this drug immediately and contact health care provider if a serious side effect occurs.
Stop this drug and contact health care provider if tendon pain, swelling, or inflammation develops or you have weakness or are unable to use 1 of your joints; rest and do not exercise.
Stop this drug at once and contact physician if symptoms of peripheral neuropathy develop.
Contact physician immediately if any muscle weakness worsens or respiratory problems develop or if watery and bloody stools occur; contact physician if persistent headache (with or without blurred vision) occurs.
Stop this drug immediately at first sign of rash or other symptoms of allergic reaction.