Original Article

Efficacy of Nitazoxanide, Nitazoxanide-Garlic Combination and Tinidazole in Treatment of Giardia duodenalis and Blastocystis hominis: Coproscopic Assessment


Background: Giardia duodenalis and Blastocystis hominis are among the most common intestinal protozoa worldwide. Treatment of infection by metronidazole (MTZ) has some limitations. The objective of this study was to detect the prevalence of Blastocystis and giardiasis among school-age children from December 2021 till March 2022 from Motoubes, Kafrelsheikh, Egypt, and determine the efficacy of nitazoxanide (NTZ), NTZ plus garlic and tinidazole (TIN) on Blastocystis and giardiasis infection.

Methods: Stool samples were collected from 390 children and microscopically examined using formalin-ethyl acetate concentration and culturing on Jones' medium for B. hominis. Those who tested positive for giardiasis (120 children, 30.7%) (Group I) or Blastocystis (180 children, 46.1%) (Group II) were equally divided into four subgroups. The first subgroup received NTZ orally, every 12 hours for three successive days. The second subgroup received NTZ in the same dose as the first subgroup plus dry garlic powder every 12 hours for three successive days. The third subgroup received TIN as a single oral dose, and a fourth control subgroup. Successful cure was considered if no Blastocystis or giardiasis stages were found in post-treatment faecal specimens.

Results: Cure rate was significantly higher in TIN treated groups (75.5% and 96.6%) than NTZ (57.7% and 40% ) or NTZ plus garlic treated groups ( 55.5% and 43%) in both Blastocystis and giardiasis, respectively (P<0.05).

Conclusion: TIN, once, is more efficacious than NTZ or NTZ plus garlic in the treatment of Blastocystis and giardiasis in children.

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IssueVol 18 No 1 (2023) QRcode
SectionOriginal Article(s)
Giardia duodenalis Blastocystis hominis Tinidazole Nitazoxanide Garlic

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How to Cite
Abdo S, Ghallab MMIG, Zaghloul MS, Elhadad H. Efficacy of Nitazoxanide, Nitazoxanide-Garlic Combination and Tinidazole in Treatment of Giardia duodenalis and Blastocystis hominis: Coproscopic Assessment. Iran J Parasitol. 2023;18(1):48-55.