Norfloxacin (PrNorfloxacin)

Product Information

• Name: PrNorfloxacin
• Active Ingredient: Norfloxacin
• Strength: 400 mg tablets
• Manufacturer: AA Pharma Inc.

Therapeutic Classification

• Class: Antibacterial Agent

Mechanism of Action

• Norfloxacin is a quinolone carboxylic acid antibacterial agent that inhibits bacterial DNA synthesis and is bactericidal.
• Specific actions include inhibition of DNA gyrase, relaxation of supercoiled DNA, and promotion of double-stranded DNA breakage.

Indications and Clinical Use

• Urinary Tract Infections: Treatment of upper and lower urinary tract infections caused by susceptible strains of various bacteria, including E. coli, Klebsiella spp., Enterobacter spp., Proteus mirabilis, Staphylococcus aureus, Streptococcus faecalis, and Pseudomonas aeruginosa.
• Gonococcal Infections: Treatment of gonococcal urethritis or cervicitis due to Neisseria gonorrhoeae.

Dosage and Administration

• Urinary Tract Infections: 400 mg twice daily for 7-10 days. For uncomplicated acute cystitis in women, the duration can be reduced to 3 days.
• Gonococcal Infections: 800 mg as a single dose.

Contraindications

• Known hypersensitivity to norfloxacin or other quinolone antibacterial agents.
• Use in patients with a history of convulsions or conditions predisposing to seizures should be cautious.

Adverse Effects

• Common: Nausea, dizziness, headache, rash, gastrointestinal disturbances.
• Serious: Tendonitis, tendon rupture, peripheral neuropathy, neuropsychiatric effects, hemolytic reactions in G6PD-deficient patients, photosensitivity, and potential retinal detachment.

Warnings and Precautions

• Tendinitis and Tendon Rupture: Rare but serious; discontinue if symptoms occur.
• Convulsions: Use cautiously in individuals with a history of seizures.
• Photosensitivity: Avoid excessive sunlight exposure.
• Hydration: Maintain adequate hydration to prevent crystalluria.
• Pregnancy: Safety in pregnant women is not established; use only if benefits justify risks.
• Nursing Mothers: Not detected in human milk but caution is advised.
• Elderly: Dosage adjustments generally not required for those with normal renal function.

Drug Interactions

• Probenecid: Reduces urinary excretion of norfloxacin.
• Theophylline: May lead to elevated plasma levels and toxicity.
• Cyclosporine: Elevated serum levels with concomitant use.
• Warfarin: Enhanced anticoagulant effect.
• Multivitamins and Antacids: Should not be administered concurrently or within 2 hours of norfloxacin.

Pharmacokinetics

• Absorption: Rapid with peak serum concentrations within 1-1.5 hours after oral administration.
• Excretion: Primarily renal, with approximately 25-30% of a dose recovered unchanged in urine.
• Half-life: Approximately 3 hours in healthy adults; prolonged in renal impairment.