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Hymenolepis diminuta Infection


Chelsea Marie

, PhD, University of Virginia;

William A. Petri, Jr

, MD, PhD, University of Virginia School of Medicine

Last review/revision Dec 2021 | Modified Sep 2022
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H. diminuta, the rat tapeworm, has a life cycle similar to the indirect cycle of Hymenolepis nana Hymenolepis nana (Dwarf Tapeworm) Infection Hymenolepis nana, a tiny intestinal tapeworm, is one of the most common human cestodes; the life cycle does not require an intermediate host. Infection is treated with praziquantel or... read more in grain insects. H. diminuta is 20 to 60 cm in length. Human infection is usually asymptomatic, it but can cause mild gastrointestinal symptoms.

Diagnosis is by finding characteristic eggs in stool.

Treatment of Hymenolepis diminuta Infection

  • Praziquantel

  • Alternatively, nitazoxanide or, outside the US, niclosamide

H. diminuta infection is effectively treated with

  • Praziquantel 25 mg/kg orally once

Alternatives include nitazoxanide and niclosamide (not available in the US).

For nitazoxanide, dosage is

  • For patients > 11 years: 500 mg orally 2 times a day for 3 days

  • For children aged 4 to 11 years: 200 mg orally 2 times a day for 3 days

  • For children aged 1 to 4 years: 100 mg orally 2 times a day for 3 days

For niclosamide, dosage is

  • For adults: 2 g orally once/day for 7 days

  • For children > 34 kg: 1.5 g in a single dose on day 1, then 1 g once/day for 6 days

  • For children 11 to 34 kg: 1 g in a single dose on day 1, then 500 mg once/day for 6 days

A stool sample should be repeated one month after therapy is completed to verify cure.

Drugs Mentioned In This Article

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