NITAZOXANIDE FOR THE TREATMENT OF GIARDIA DUODENALIS INFECTION: A COMPARATIVE TRIAL WITH SECNIDAZOLE

Objective: Nitazoxanide is a 5-nitrothiazolyl derivative with broad-spectrum activity against numerous intestinal protozoa, helminths and anaerobic bacteria licensed in the United States for the treatment of Cryptosporidium spp. and Giardia duodenalis. The aim of this study was to compare the efficacy and safety of nitazoxanide (NTZ) versus secnidazole (SNZ) in the treatment of giardiasis. Method: A randomized controlled open-label trial was carried out at the Cuban Institute of Gastroenterology in adults with confirmed Giardia duodenalis mono-infection. 125 patients were randomly assigned to receive either NTZ [500 mg two times daily for three days (n= 62)] or SNZ [2 g single dose (n= 63)]. The evaluation of the efficacy was based on parasitological response. All patients were asked to provide three faecal samples on days 3, 5, and 10 after treatment completion. Patients were considered to be cured, if no Giardia trophozoites or cysts were found in any of the three post-treatment faecal specimens evaluated by direct wet mounts and/or after Ritchie concentration techniques. Results: The frequency of cure was a little higher for NTZ [95.2%- (59/62)] than for SNZ [93.7%- (59/63)] but the difference was not statistically significant (P>0.05). Bitter taste was only reported in SNZ treated group were as yellowish coloration of the urine and rash were only reported in NTZ treated group. Nausea and headache were more common in patients treated with SNZ (P<0.05). Conclusion: NTZ, for three days, is as efficacious as a single dose SNZ in the treatment of giardiasis in adults.