Drug Nomenclature
International Nonproprietary Names (INNs) in main languages (French, Latin, Russian, and Spanish):
Adverse Effects and Precautions
As for Ciprofloxacin. Symptomatic hyperglycaemia and/or hypoglycaemia have been reported in patients (usually diabetics) taking gatifloxacin. However, hypoglycaemia, and particularly hyperglycaemia, have occurred in non-diabetic patients. Severe life-threatening events, including hyperosmolar nonketotic hyperglycaemic coma, diabetic ketoacidosis, hypoglycaemic coma, convulsions, and mental status changes have been reported very rarely. Although in most cases the blood-glucose disturbance was reversible, fatalities have been reported. Gatifloxacin should not be given to diabetic patients.
Other risk factors for developing blood-glucose disturbances include older age (patients 65 years of age or over), renal impairment, or use of other drugs that alter blood-glucose concentrations, particularly hypoglycaemics. Patients with risk factors should have their blood-glucose concentrations closely monitored and if signs or symptoms of glucose disturbances develop, gatifloxacin should be stopped.
Effects on glucose metabolism
Hypoglycaemia and hyperglycaemia have been associated with gatifloxacin in both diabetic and non-diabetic patients. A review of spontaneous adverse effects reported to the FDA in the United States of America (US) between November 1997 and September 2003 found the rate of blood-glucose disturbances with gatifloxacin to be 10-fold higher when compared with ciprofloxacin, levofloxacin, and moxifloxacin.
Subsequent population-based case-control studies in elderly patients given fluoroquinolones (ciprofloxacin, gatifloxacin, levofloxacin, or moxifloxacin), second-generation cephalosporins, or macrolides also found an increased risk of blood-glucose disturbances with gatifloxacin.
While blood-glucose disturbances appear to be mainly associated with gatifloxacin, the possibility that they may also be a class effect of fluoroquinolones cannot be excluded; patients most at risk are the elderly, those with diabetes and/or those taking hypoglycaemic drugs, and patients with impaired renal function. Twenty two case reports of dysglycaemia associated with the use of levofloxacin were received by Health Canada between January 1997 and June 2006; reported cases included 15 diabetic patients. In contrast a review of the effects of moxifloxacin on blood glucose, including data from large postmarketing studies, suggested it had no significant effect.n
Interactions
As for Ciprofloxacin. Use of gatifloxacin with drugs that alter blood-glucose concentrations increases the risk of blood-glucose disturbances.
Antidiabetics
Given the adverse effects of gatifloxacin, phar-macodynamic interactions with antidiabetics might reasonably be anticipated. Severe and persistent hypoglycaemia occurred in 3 patients taking oral hypoglycaemics (repaglinide, glibenclamide and pioglitazone, and glimepiride) when gatifloxacin was added to their therapy.
Antimicrobial Action
As for Ciprofloxacin. Gatifloxacin is reported to have greater activity against Gram-positive bacteria, including pneumococci, than ciprofloxacin.
Pharmacokinetics
Gatifloxacin is readily absorbed from the gastrointestinal tract with an absolute bioavailability of 96%. Peak plasma concentrations occur within 1 to 2 hours of an oral dose. Gatifloxacin is widely distributed into body tissues and is about 20% bound to plasma proteins. It undergoes limited metabolism and has an elimination half-life of 7 to 14 hours. Gatifloxacin is excreted primarily unchanged in the urine with less than 1% as metabolites. About 5% is also excreted unchanged in the faeces. Distribution into milk occurs in animals.
Uses and Administration
Gatifloxacin is a fluoroquinolone antibacterial with actions and uses similar to those of ciprofloxacin. It is given orally, or by intravenous infusion as a 2 mg/mL solution over 60 minutes, for the treatment of susceptible infections, including respiratory- and urinary-tract infections and skin infections. The usual adult dose is 400 mg once daily. A single dose of 400 mg or a dose of 200 mg daily for 3 days may be adequate for uncomplicated urinary-tract infections. For details of reduced doses to be used in renal impairment, see below. A single dose of 400 mg may also be given for the treatment of uncomplicated gonorrhoea. Gatifloxacin is also used as 0.3% eye drops for the treatment of bacterial conjunctivitis.
Administration in renal impairment
Doses of gatifloxacin should be reduced in patients with renal impairment; the usual initial dose of 400 mg should be followed by reduced maintenance doses of 200 mg daily in those with a creatinine clearance of less than 40 mL/minute and in those on haemodialy sis or continuous peritoneal dialysis.
Preparations
Proprietary Preparations
Argentina: Gati; Tequin; Zymaran; Australia: Tequin; Brazil: Tequin; Zymar; Canada: Tequin; Zymar; Chile: Starox; Zymar; Germany; Bonoq; India: Biogat; Gaticin; Gatiquin; Gatt; Zyquin; Indonesia: Gaticin; Gatimax; Jpn; Gatiflo; Malaysia: Tequin; Mexico: Tequin; Zymar; New Zealand: Tequin; Philippines: Tequin; Zymar; South Africa: Tequin; Singapore: Tequin; Zymar; Thailand: Tequin; Zymar; US (USA): Tequin; Zymar
Multi-ingredient
India: Gatiquin Oz Kit.