Aspects of the pharmacology and pharmacokinetics of nitroimidazoles with special reference to tinidazole.

Tinidazole has been reported to be highly effective against trichomoniasis, giardiasis and amoebiasis. In vitro, tinidazole is more active against trichomonads than metronidazole and possesses antiprotozoal activity at least comparable to metronidazole against Entamoeba histolytica, Tinidazole gives higher serum levels in animals following oral administration than metronidazole and is well distributed in organs and tissues. When tinidazole or metronidazole is given to healthy volunteers at a dose of 2g orally, the serum level of tinidazole at 48h is considerably higher than that of metronidazole. At 72h tinidazole is still present but metronidazole is not. These pharmacokinetic differences result from the longer half-life of tinidazole. These findings suggest that tinidazole might prove to be more useful than metronidazole in the treatment of protozoal infections when given in once daily oral doses of 2g.