ofloxacin

Action

Inhibits bacterial DNA synthesis by inhibiting DNA gyrase in susceptible bacteria

Availability

Ophthalmic solution: 3 mg/ml (0.3%)

Otic solution: 0.3%

Tablets: 200 mg, 300 mg, 400 mg

Indications and dosages

➣ Prostatitis caused by Escherichia coli

Adults: 300 mg P.O. q 12 hours for 6 weeks

➣ Complicated urinary tract infections caused by E. coli, Klebsiella pneumoniae, or Proteus mirabilis

Adults: 200 mg P.O. q 12 hours for 10 days

➣ Uncomplicated cystitis caused by E. coli or K. pneumoniae

Adults: 200 mg P.O. q 12 hours for 3 days

➣ Acute uncomplicated urethral and cervical gonorrhea

Adults: 400 mg P.O. as a single dose

➣ Nongonococcal cervicitis or urethritis caused by Chlamydia trachomatis; mixed infections of cervix or urethra caused by C. trachomatis or Neisseria gonorrhoeae

Adults: 300 mg P.O. q 12 hours for 7 days

➣ Acute bacterial exacerbation of chronic bronchitis, community-acquired pneumonia, and uncomplicated skin and skin-structure infections caused by susceptible organisms

Adults: 400 mg P.O. q 12 hours for 10 days

➣ Acute pelvic inflammatory disease

Adults: 400 mg P.O. q 12 hours for 10 to 14 days

➣ Bacterial conjunctivitis

Adults and children ages 1 and older: One to two drops of ophthalmic solution in affected eye q 2 to 4 hours on days 1 and 2; then one to two drops q.i.d. on days 3 through 7

➣ Corneal ulcers

Adults: One to two drops of ophthalmic solution in affected eye q 30 minutes while awake on days 1 and 2, then one to two drops q hour while awake on days 3 to 7, then one to two drops q.i.d. while awake on days 7 to 9

➣ Otitis externa

Adults and children ages 13 and older: 10 drops of otic solution into affected ear daily for 7 days

➣Chronic suppurative otitis media with perforated tympanic membrane

Adults and children ages 12 and older: 10 drops of otic solution into affected ear b.i.d. for 14 days

Dosage adjustment

• Renal impairment

• Severe hepatic impairment

Contraindications

• Hypersensitivity to drug or other fluoroquinolones

Precautions

Use cautiously in:

• underlying CNS disease, renal impairment, cirrhosis, bradycardia, acute myocardial ischemia

• known history of myasthenia gravis (avoid use)

• history of tendinitis or tendon rupture with fluoroquinolone use

• dialysis patients

• elderly patients

• pregnant or breastfeeding patients (safety not established except in postex-posure inhalation or cutaneous anthrax).

• children younger than age 18 (except in postexposure inhalation or cutaneous anthrax and in ophthalmic and otic use).

Administration

• Don't give zinc- or iron-containing drugs within 2 hours of ofloxacin.

Adverse reactions

CNS: dizziness, drowsiness, headache, light-headedness, insomnia, acute psychoses, agitation, confusion, tremors, hallucinations, increased intracranial pressure, seizures

CV: chest pain, vasodilation

GI: nausea, diarrhea, constipation, abdominal pain, pseudomembranous colitis

GU: interstitial cystitis, vaginitis

Hematologic: eosinophilia, leukopenia

Musculoskeletal: tendinitis, tendon rupture, joint pain, back pain

Skin: rash, photosensitivity, phototoxicity, Stevens-Johnson syndrome

Other: altered taste, superinfection, myasthenia gravis exacerbation

Interactions

Drug-drug. Amiodarone, bepridil, disopyramide, erythromycin, pentamidine, phenothiazines, pimozide, procainamide, quinidine, sotalol, tricyclic antidepressants: increased risk of serious adverse cardiovascular reactions

Antacids, bismuth subsalicylate, iron or zinc salts, sucralfate: decreased ofloxacin absorption

Corticosteroids: increased risk of tendon rupture

Probenecid: decreased renal elimination of ofloxacin

Theophylline: increased theophylline blood level and possible toxicity

Warfarin: increased warfarin effects

Drug-diagnostic tests. Alanine aminotransferase, aspartate aminotransferase, platelets: increased levels

Hemoglobin, hematocrit: decreased values

Drug-food. Milk or yogurt (consumed alone), tube feedings: impaired drug absorption

Drug-herbs. Fennel: decreased drug absorption

Dong quai, St. John's wort: phototoxicity

Drug-behaviors. Sun exposure: phototoxicity

Patient monitoring

• Assess patient for signs and symptoms of superinfection.

• Inspect for rash. Check for signs and symptoms of hypersensitivity reaction.

☞ Watch for fever with diarrhea; diarrhea containing pus; or severe, persistent diarrhea; and tendinitis or tendon rupture.

• Evaluate neurologic status closely.

Patient teaching

• Encourage patient to maintain fluid intake of at least 1,500 ml daily to prevent crystalluria.

• Inform patient being treated for gonorrhea that partners must be treated.

☞ Tell patient to immediately report fever and diarrhea, especially if stool contains blood, pus, mucus. Caution him not to treat diarrhea without consulting prescriber.

☞ Instruct patient to stop taking drug and immediately report rash or tendon pain or inflammation.

• Instruct patient not to take iron- or zinc-containing drugs or antacids within 2 hours of ofloxacin.

• Teach patient ways to counteract photosensitivity, such as by wearing sunglasses and avoiding excessive exposure to bright light.

• Teach patient how to use eye or ear drops. Caution him not to touch dropper tip to any surface (including eye or ear).

• As appropriate, review all other significant and life-threatening adverse reactions and interactions, especially those related to the drugs, tests, foods, herbs, and behaviors mentioned above.