Indications
Tinidazole is prescribed for the treatment of infections caused by certain protozoa. It is effective against trichomoniasis due to Trichomonas vaginalis in both female and male patients. Additionally, tinidazole is indicated for the treatment of giardiasis caused by Giardia duodenalis (formerly known as G. lamblia) in both adults and pediatric patients over three years old. It is also used in the management of intestinal amebiasis and amebic liver abscess caused by Entamoeba histolytica in the same age groups.
Pharmacodynamics
As a synthetic antiprotozoal agent, tinidazole displays potent activity against certain protozoa both in laboratory studies and in clinical infections. It is effective against Trichomonas vaginalis, Giardia duodenalis, and Entamoeba histolytica. However, it is important to note that tinidazole does not exhibit significant activity against most strains of vaginal lactobacilli, which are considered beneficial flora.
Absorption
Tinidazole is rapidly and completely absorbed when administered on an empty stomach. When taken with food, there is a delay in the time to reach maximum concentration (Tmax) by approximately two hours, and there is a reduction in the peak plasma concentration (Cmax) by about 10%. The average area under the curve (AUC) with food is 901.6 ± 126.5 mcg hr/mL, indicating·he liver, primarily mediated by the enzyme CYP3A4. Like metronidazole, tinidazole is significantly metabolized in humans before it is excreted. The metabolic processes include oxidation, hydroxylation, and conjugation. After administration in humans, tinidazole remains the predominant drug-related component in plasma, accompanied by a minor quantity of the 2-hydroxymethyl metabolite.
Mechanism of Action
Tinidazole functions as a prodrug and antiprotozoal agent with its mechanism of action initiated by the reduction of its nitro group within Trichomonas through a ferredoxin-mediated electron transport system. This process generates free nitro radicals, which are believed to play a crucial role in its antiprotozoal effectiveness. These radicals are thought to bind covalently to DNA, resulting in DNA damage and ultimately leading to cell death. Although the precise mechanism by which tinidazole acts against Giardia and Entamoeba species has not been definitively established, it is likely to follow a similar pathway.
