Oral, I.V.: Treatment of the following infections when caused by susceptible bacteria: Acute bacterial exacerbation of chronic bronchitis; acute sinusitis; community-acquired pneumonia including pneumonia caused by multidrug-resistant S. pneumoniae (MDRSP); uncomplicated skin and skin structure infection; uncomplicated urinary tract infections (cystitis); complicated urinary tract infections; pyelonephritis; uncomplicated urethral and cervical gonorrhea; acute, uncomplicated rectal infections in women

Ophthalmic: Bacterial conjunctivitis

Severe hypersensitivity reactions, including anaphylaxis, have occurred with quinolone therapy. If an allergic reaction occurs (itching, urticaria, dyspnea, facial edema, loss of consciousness, tingling, cardiovascular collapse) discontinue drug immediately. Prolonged use may result in superinfection; pseudomembranous colitis may occur and should be considered in all patients who present with diarrhea. Quinolones may exacerbate myasthenia gravis, use with caution (rare, potentially life-threatening weakness of respiratory muscles may occur). May cause peripheral neuropathy (rare); discontinue if symptoms of sensory or sensorimotor neuropathy occur.

Safety and efficacy for ophthalmic use have not been established in children <1 year of age. Safety and efficacy for systemic use have not been established in patients <18 years of age.

Systemic therapy:

3% to 10%:

Central nervous system: Headache (3%), dizziness (3%)

Gastrointestinal: Nausea (8%), diarrhea (4%)

Genitourinary: Vaginitis (6%)

Local: Injection site reactions (5%)

0.1% to 3%: Abdominal pain, abnormal dreams, abnormal vision, agitation, alkaline phosphatase increased, allergic reaction, anorexia, anxiety, arthralgia, back pain, chest pain, chills, confusion, constipation, diaphoresis, dry skin, dyspepsia, dyspnea, dysuria, facial edema, fever, flatulence, gastritis, glossitis, hematuria, hyperglycemia, hypertension, insomnia, leg cramps, mouth ulceration, nervousness, oral candidiasis, palpitation, paresthesia, peripheral edema, pharyngitis, pruritus, rash, serum amylase increased, serum bilirubin increased, serum transaminases increased, somnolence, stomatitis, taste perversion, thirst, tinnitus, tremor, weakness, vasodilation, vertigo, vomiting

<0.1%: Abnormal thinking, arthritis, asthenia, ataxia, bone pain, bradycardia, breast pain, bronchospasm, cheilitis, colitis, cyanosis, depersonalization, depression, diabetes mellitus, dysphagia, ear pain, ecchymosis, edema, epistaxis, ethanol intolerance, euphoria, eye pain, gastrointestinal hemorrhage, gingivitis, halitosis, hallucination, hematemesis, hematuria, hostility, hyperesthesia, hypertonia, hyperventilation, hypoglycemia, lymphadenopathy, maculopapular rash, metrorrhagia, migraine, myalgia, myasthenia, neck pain, panic attacks, paranoia, parosmia, photophobia, pseudomembranous colitis, psychosis, ptosis, rectal hemorrhage, seizure, stress, tachycardia, taste disturbance, tongue edema, vesiculobullous rash

Postmarketing and/or case reports: Acute renal failure, anaphylactic reaction, angioneurotic edema, hepatitis, INR increased, prothrombin time increased, severe hyper-/hypoglycemia, nonketotic hyperglycemia, pancreatitis, peripheral neuropathy, Stevens-Johnson syndrome, syncope, tendon rupture, thrombocytopenia, torsade de pointes

Ophthalmic therapy:

5% to 10%: Ocular: Conjunctival irritation, keratitis, lacrimation increased, papillary conjunctivitis

1% to 4%:

Central nervous system: Headache

Gastrointestinal: Taste disturbance

Ocular: Chemosis, conjunctival hemorrhage, discharge, dry eye, edema, irritation, pain, visual acuity decreased

Corticosteroids: Concurrent use may increase the risk of tendon rupture, particularly in elderly patients (overall incidence rare).

Hypoglycemic agents: Gatifloxacin may alter glucose control in patients receiving hypoglycemic agents with or without insulin. Cases of severe disturbances (including symptomatic hypoglycemia) have been reported, typically within 1-3 days of gatifloxacin initiation.

Metal cations (aluminum, calcium, iron, magnesium, and zinc) bind quinolones in the gastrointestinal tract and inhibit absorption. Concurrent administration of most antacids (not calcium carbonate), oral electrolyte supplements, quinapril, sucralfate, and some didanosine formulations (chewable/buffered tablets and pediatric powder for oral suspension) should be avoided. Gatifloxacin should be administered 4 hours before these agents.

Probenecid: May decrease renal secretion of quinolones.

QTc-prolonging agents: Effects may be additive with gatifloxacin. Use caution with Class Ia and Class III antiarrhythmics, erythromycin, cisapride, antipsychotics, and cyclic antidepressants.

Warfarin: The hypoprothrombinemic effect of warfarin may be enhanced by some quinolone antibiotics; monitor INR.

Ophthalmic solution: Store between 15°C to 25°C (59°F to 77°F). Do not freeze.

Powder for oral suspension: Prior to reconstitution, store at 25°C (77°F); do not freeze. Reconstitute with appropriate amount of water as specified on bottle. Shake vigorously until suspended. Following reconstitution, store under refrigeration at 2°C to 8°C (36°F to 46°F); do not freeze. Discard any unused portion after 14 days.

Solution for injection: Store at 25°C (77°F). Do not freeze. Single-use vials must be diluted to a concentration of 2 mg/mL prior to administration; do not dilute with SWFI (a hypertonic solution results). Following dilution, stable for 14 days.

Tablet: Store at 25°C (77°F).

Y-site administration: Compatible: Acyclovir, alfentanil, amikacin, aminophylline, ampicillin, ampicillin/sulbactam, aztreonam, bretylium, buprenorphine, butorphanol, calcium chloride, calcium gluconate, carboplatin, cefazolin, cefotetan, ceftazidime, ceftizoxime, ceftriaxone, chlorpromazine, cimetidine, cisatracurium, cisplatin, clindamycin, cyclophosphamide, cyclosporine, cytarabine, dexamethasone sodium phosphate, digoxin, diphenhydramine, dobutamine, dopamine, doxorubicin, droperidol, enalaprilat, esmolol, etoposide, famotidine, fentanyl, fluconazole, fluorouracil, ganciclovir, gemcitabine, gentamicin, granisetron, haloperidol, hydrocortisone sodium succinate, hydromorphone, hydroxyzine, ifosfamide, imipenem/cilastatin, labetalol, leucovorin, lidocaine, lorazepam, magnesium sulfate, mannitol, meperidine, mesna, methotrexate, methylprednisolone sodium succinate, metoclopramide, metronidazole, midazolam, mitoxantrone, morphine, nalbuphine, naloxone, nicardipine, nitroglycerin, ondansetron, paclitaxel, pentamidine, pentobarbital, phenobarbital, potassium chloride, prochlorperazine edisylate, promethazine, propranolol, ranitidine, remifentanil, sodium bicarbonate, sodium phosphates, sufentanil, theophylline, ticarcillin, ticarcillin/clavulanate potassium, tobramycin, trimethoprim/sulfamethoxazole, vecuronium, verapamil, vinblastine, vincristine, vinorelbine, zidovudine. Incompatible: Amphotericin B, amphotericin B cholesteryl sulfate complex, cefoperazone, cefoxitin, diazepam, furosemide, heparin, phenytoin, piperacillin, piperacillin/tazobactam, potassium phosphates, vancomycin

Absorption: Oral: Well absorbed; Ophthalmic: Not measurable

Distribution: Vd: 1.5-2.0 L/kg; concentrates in alveolar macrophages and lung parenchyma

Protein binding: 20%

Metabolism: Only 1%; no interaction with CYP

Bioavailability: 96%

Half-life elimination: 7.1-13.9 hours; ESRD/CAPD: 30-40 hours

Time to peak: Oral: 1 hour

Excretion: Urine (70% as unchanged drug, <1% as metabolites); feces (5%)

Children 1 year and Adults: Ophthalmic: Bacterial conjunctivitis:

Days 1 and 2: Instill 1 drop into affected eye(s) every 2 hours while awake (maximum: 8 times/day)

Days 3-7: Instill 1 drop into affected eye(s) up to 4 times/day while awake

Adults: Oral, I.V.:

Acute bacterial exacerbation of chronic bronchitis: 400 mg every 24 hours for 5 days

Acute sinusitis: 400 mg every 24 hours for 10 days

Community-acquired pneumonia: 400 mg every 24 hours for 7-14 days

Uncomplicated skin/skin structure infections: 400 mg every 24 hours for 7-10 days

Uncomplicated urinary tract infections (cystitis): 400 mg single dose or 200 mg every 24 hours for 3 days

Complicated urinary tract infections: 400 mg every 24 hours for 7-10 days

Acute pyelonephritis: 400 mg every 24 hours for 7-10 days

Uncomplicated urethral gonorrhea in men, cervical or rectal gonorrhea in women: 400 mg single dose

Elderly: No dosage adjustment is required based on age, however, assessment of renal function is particularly important in this population.

Dosage adjustment in renal impairment: Creatinine clearance <40 mL/minute (or patients on hemodialysis/CAPD) should receive an initial dose of 400 mg, followed by a subsequent dose of 200 mg every 24 hours. Patients receiving single-dose or 3-day therapy for appropriate indications do not require dosage adjustment. Administer after hemodialysis.

Dosage adjustment in hepatic impairment: No dosage adjustment is required in mild-moderate hepatic disease. No data are available in severe hepatic impairment (Child-Pugh Class C).

Oral: May be administered with or without food, milk, or calcium supplements. Gatifloxacin should be taken 4 hours before supplements (including multivitamins) containing iron, zinc, or magnesium. Suspension may be administered through a gastric feeding tube.

I.V.: For I.V. infusion only. Concentrated injection (10 mg/mL) must be diluted to 2 mg/mL prior to administration. No further dilution is required for premixed 100 mL and 200 mL solutions. Infuse over 60 minutes. Avoid rapid or bolus infusions.

I.V.: Report any redness, pain, itching, burning, or signs of irritation at infusion site; swelling of mouth, lips, or tongue, back pain, tendon pain; dizziness, abnormal thinking, or anxiety

Ophthalmic: Tilt head back and instill drops in affected eye at often as directed for length of time prescribed. Do not allow touch dropper to any surface, including the eyes or hands. Apply light pressure to the inside corner of the eye (near the nose) after each drop. Do not wear contact lenses if being treated for a bacterial eye infection. May cause some temporary stinging, burning, itching, redness or tearing; eyelid swelling or itching, or a bad taste in you mouth after instillation. Report persistent pain, burning, swelling, or visual disturbances.

Oral: Take exactly as directed with or without food. Avoid alcohol. Take 4 hours before antacids or mineral supplements (iron, magnesium, or zinc). Do not miss a dose (take a missed dose as soon as possible unless it is almost time for next dose). Take entire prescription even if feeling better. Maintain adequate hydration (2-3 L/day of fluids, unless instructed to restrict fluids). May cause nausea, vomiting, taste perversion (small, frequent meals, good mouth care, chewing gum, or sucking hard candy may help); headache, dizziness, insomnia, anxiety (use caution when driving or engaging in tasks requiring alertness until response is known). Report immediately any CNS changes (dizziness, insomnia, hallucinations, suicidal ideation or actions); rash or itching; respiratory difficulty or swallowing; tendon pain; swelling of mouth, lips, tongue, or throat; chest pain or tightness; or back pain. Report changes in voiding pattern, vaginal itching, burning, or discharge; vision changes or hearing; abnormal bruising or bleeding or blood in urine; or other adverse reactions.

Injection, infusion [premixed in D5W] (Tequin®): 200 mg (100 mL); 400 mg (200 mL)

Injection, solution [preservative free] (Tequin®): 10 mg/mL (40 mL)

Powder for oral suspension (Tequin®): 200 mg/5 mL (25 mL, 50 mL, 75 mL, 100 mL) [contains phenylalanine 168 mg/5 mL; fruit flavor]

Solution, ophthalmic (Zymar™): 0.3% (5 mL) [contains benzalkonium chloride]

Tablet (Tequin®): 200 mg, 400 mg

Blondeau JM, "Expanded Activity and Utility of the New Fluoroquinolones: A Review,"Clinical Therapeutics, 1999, 21(1):3-40.

"Gatifloxacin and Moxifloxacin: Two New Fluoroquinolones,"The Medical Letter, 2000, Vol 42, 1072:15.

Perry CM, Barman Balfour JA, Lamb HM, "Gatifloxacin,"Drugs, 1999, 58(4):683-96.