infectious diseases
Metronidazole and Tinidazole
Pharmacokinetics
Oralmetronidazoleis absorbed well. It is usually given IV only if patients cannot be treated orally. It is distributed widely in body fluids and penetrates into cerebrospinal fluid, resulting in high concentrations. Metronidazoleis metabolized presumably in the liver and excreted mainly in urine, but elimination is not decreased in patients with renal insufficiency. However, becausemetronidazolemetabolites may accumulate in patients with end-stage renal disease, these patients should be monitored formetronidazole-associated adverse effects such as central nervous system effects, including headaches, convulsions, and peripheral neuropathy (mainly numbness or paresthesias in an extremity). Tinidazolehas a slightly longer half-life thanmetronidazole, allowing for less frequent dosing. 