Tinidazole Cimetidine

Cimetidine reduces the metabolism of tinidazole, and possibly also metronidazole, but this is probably not clinically important. 

In a study in 6 healthy subjects cimetidine 400 mg twice daily for 7 days raised the peak serum levels of a single 600-mg dose of tinidazole by 21%, increased the 24-hour AUC by 40% and increased the half-life by 47%, from 7.66 to 11.23 hours. ... 

Cimetidine is a well known enzyme inhibitor, which probably inhibits the metabolism of the metronidazole and tinidazole by the liver. 

The modest changes in the pharmacokinetics of tinidazole with cimetidine seem unlikely to be clinically significant, but bear them in mind in the case of an unexpected response to treatment. The interaction between metronidazole and cimetidine is not established, but any changes in metronidazole pharmacokinetics seem to be modest and unlikely to be important. 

Patel RB, Shah GF, Raval JD, Gandhi TP, Gilbert RN. The effect of cimetidine andii mpicin on tinidazole kinetics in healthy human volunteers.(1986) 23,338-41. 

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