Benznidazole Chemical formula
Synonyms: Benznidazol; Benznidazolum; Ro-7-1051. N-Benzyl-2-(2-nitroimidazol-1-yl)acetamide.
Cyrillic synonym: Бензнидазол.

💊 Chemical information

Chemical formula: C12H12N4O3 = 260.2.
CAS — 22994-85-0.
ATC — P01C A02.


In Int.

💊 Adverse Effects

Nausea, vomiting, abdominal pain, peripheral neuropathy, blood dyscrasias, and severe skin reactions have been reported with benznidazole.
1. Apt W, et al. Clinical trial of benznidazole and an immunopotentiator against Chagas disease in Chile. Trans R Soc Trop Med Hyg 1986; 80: 1010.

💊 Pharmacokinetics

Benznidazole is absorbed from the gastrointestinal tract after oral doses.
1. Raaflaub J, Ziegler WH. Single-dose pharmacokinetics of the trypanosomicide benznidazole in man. Arzneimittelforschung 1979; 29: 1611–14.

💊 Uses and Administration

Benznidazole is a 2-nitroimidazole derivative with antiprotozoal activity. It is of value in the treatment of American trypanosomiasis (Chagas’ disease) due to infection with Trypanosoma cruzi, especially during the early acute stage of the disease. Benznidazole has been given orally in a dose of 5 to 7 mg/kg daily in two divided doses usually for 60 days (but see below). Children have been given 10 mg/kg daily in two divided doses.

American trypanosomiasis.

Available treatment for American trypanosomiasis is generally unsatisfactory, but benznidazole is of value especially in the acute phase. WHO1 recommends that benznidazole should be given for 60 days but some in the USA2 suggest courses of 30 to 90 days. Although treatment is usually confined to the acute phase of the disease, therapy during the early chronic phase was reported to be beneficial,3and long-term follow-up in patients who had received benznidazole has shown a reduction in cardiac complications and parasitaemia.4
1. WHO. Control of Chagas disease: second report of the WHO expert committee. WHO Tech Rep Ser 905 2002. Available at: (accessed 17/07/08
2. Abramowicz M, ed. Drugs for parasitic infections. 1st ed. New Rochelle NY: The Medical Letter, 2007
3. de Andrade ALSS, et al. Randomised trial of efficacy of benznidazole in treatment of early Trypanosoma cruzi infection. Lancet 1996; 348: 1407–13
4. Viotti R, et al. Treatment of chronic Chagas’ disease with benznidazole: clinical and serologic evolution of patients with longterm follow-up. Am Heart J 1994; 127: 151–62.

💊 Preparations

Proprietary Preparations

Arg.: Radanil; Braz.: Rochagan; Ecuad.: Ragonil.
Published October 19, 2018.