Norfloxacin

C. diff Risk

High

Oral Bioavailability

Moderate

Approximate Cost

Non-formulary

Dosing

Adult

400 mg PO BID

General Information

Unacceptable Uses

Non-formulary

Common Usage

Prophylaxis of spontaneous bacterial peritonitis.
Urinary tract infection
Prostatitis

Uncomplicated UTI.

Drug Monitoring

Monitor QTc in patients with increased risk

Adverse Effects

  • QTc prolongation

  • Dysglycemia

  • Rash

  • Tendinopathy and rupture

  • GI upset

  • Increased liver enzymes

  • Weakness exacerbation in myasthenia gravis

  • CNS toxicity including confusion, psychosis

  • Leukopenia, thrombocytopenia

Major Interactions

Other QTc prolonging agents.

Divalent cations - Decreased absoprtion.

Methadone - Increased seizures.

Thyroid replacement - Decreases T.

Warfarin - Increased INR.

Pharmacology

Antimicrobial class: Fluoroquinolone

Pregnancy category: C

Average serum half life: 4 hours

Biliary penetration: Therapeutic

CSF penetration: Poor

Urine penetration: Therapeutic