Efficacy of some metronidazole derivatives against Giardia lamblia, in vivo study

Document Type : Research(Original) Article


1 Basic Research in Infectious Diseases center, Shiraz University of Medical Sciences, Shiraz, Iran

2 Department of Parasitology, School of Medicine. Ahvaz University of Medical Sciences, Ahvaz Iran.

3 School of Pharmacy and pharmaceutical sciences research center, Shiraz University of Medical Sciences, Shiraz, Iran


Giardiasis is a protozoal infection of small intestine caused by giardia lamblia. The disease is usually asymptomatic though it can present as acute or chronic diarrhea. Giardiasis is a major cause of intestinal infection and Iran is an endemic area of the disease. Despite reports about drug resistance, long course treatment and various side effects, metronidazole is the drug of choice for giardiasis.In this study we investigated in vivo effects of five new derivatives (a-e) of metronidazole (MTZ) on the giardia lamblia trophozoite in infected mice. Giardia intestinalis cysts were isolated from a patient and purified by sucrose gradient method. Fifty Purified cysts were inoculated to mice and after development of infection, the new metronidazole derivatives were given to the mice and results were compared to metronidazole as positive control.Compounds a and b showed desirable antigiardiasis activity and could destroy the cyst and trophozoite of giardia lamblia in mice after both two and four days, but the activity of the other compounds appeared only after 4 days.


  1. Saebi E. Clinical parasitology, protozoal diseases in Iran. Tehran: Aeeizh; 2011.
  2. Pierce KK, Kirkpatrick BD. Update on human infections caused by intestinal protozoa. Curr Opin Gastroenterol. 2009;25(1):12-7.
  3. Feng Y, Xiao L. Zoonotic potential and molecular epidemiology of Giardia species and giardiasis. Clin Microbial Rev. 2011;24(1):110-40.
  4. Dib HH, Lu SQ, Wen SF. Prevalence of Giardia lamblia with or withoutdiarrhea in South East, South East Asia and the Far East. Parasitol Res. 2008;103(2):239-51.
  5. Dwivedi KK, Prasad G, Saini S, Mahajan S, Lal S, Baveja UK. Enteric opportunistic parasites among HIV infected individuals: associated risk factors and immune status. Jpn J Infect Dis. 2007;60(2/3):76.
  6. Bajer A. Cryptosporidium and Giardia spp. infections in humans, animals and the environment in Poland. Parasitol Res. 2008;104(1):1-17.
  7. Reynoldson J, Thompson R, Horton R. Albendazole as a future antigiardial agent. Parasitol Today. 1992;8(12):412-4.
  8. Khabnadideh S, Rezaei Z, Motazedian M, Eskandari M. Synthesis of metronidazole derivatives as antigiardiasis agents. Daru. 2007;15(1):17-20.
  9. Jokipii L, Jokipii AM. In vitro susceptibility of Giardia lamblia trophozoites to metronidazole and tinidazole. J Infect Dis. 1980;141(3):317-25.
  10. Gillin FD, Diamond LS. Inhibition of clonal growth of Giardia lamblia and Entamoeba histolytica by metronidazole, quinacrine, and other antimicrobial agents. J Antimicrob Chemother. 1981;8(4):305-16.
  11. Wright JM, Dunn LA, Upcroft P, Upcroft JA. Efficacy of antigiardial drugs. Expert Opin Drug Saf. 2003;2(6):529-41.
  12. A Escobedo A, Cimerman S, Almirall P. An old drug against giardiasis: mebendazole as a treatment option. Infect Disord Drug Targets. 2011;11(1):94-5.
  13. Lalle M. Giardiasis in the post genomic era: treatment, drug resistance and novel therapeutic perspectives. Infect Disord Drug Targets. 2010;10(4):283-94.
  14. Löfmark S, Edlund C, Nord CE. Metronidazole is still the drug of choice for treatment of anaerobic infections. Clin Infect Dis. 2010;50(Supplement 1):S16-S23.
  15. Upcroft P. Drug resistance in< i> Giardia: clinical versus laboratory isolates. Drug Resist Updat. 1998;1(3):166-8.
  16. Alizadeh A, Ranjbar M, Kashani K, Taheri M, Bodaghi M. Albendazole versus metronidazole in the treatment of patients with giardiasis in the Islamic Republic of Iran. East Mediterr Health J. 2006;12(5):548.
  17. Sadjjadi S, Alborzi A, Mostovfi H. Comparative clinical trial of mebendazole and metronidazole in giardiasis of children. J Trop Pediatr. 2001;47(3):176-8.
  18. Kavousi S. Giardiasis in infancy and childhood: a prospective study of 160 cases with comparison of quinacrine (Atabrine) and metronidazole (Flagyl). Am J Trop Med Hyg. 1979;28(1):19-23.