Successful treatment of niclosamide- and praziquantel-resistant beef tapeworm infection with nitazoxanide.

Background: Beef tapeworm (Taenia saginata) infection is acquired by eating inadequately cooked beef that contains the larvae or cysticerci of T. saginata. Niclosamide and praziquantel have proved effective for its treatment but treatment failures are well known. We report herein the results of nitazoxanide therapy.

Methods: A prospective study was conducted in 18 children and 34 adults to assess the efficacy and safety of nitazoxanide in the treatment of niclosamide- and praziquantel-resistant T. saginata infection. Nitazoxanide was administered twice daily for 3 days in 500-mg doses for those aged over 14 years and at 20mg/kg body weight/day in children aged 5-14 years. Post-treatment follow-up was undertaken at 1, 2, 4, 8, and 12 weeks for fecal samples for proglottides, and to check the presence, number, and viability of Taenia eggs.

Results: Nitazoxanide cured 51 of 52 (98.1%) patients. Mild side effects occurred in seven patients, which resolved spontaneously. There were no abnormalities in laboratory parameters.

Conclusions: Nitazoxanide is a safe, effective, inexpensive, and well-tolerated drug for the treatment of niclosamide- and praziquantel-resistant beef tapeworm infection.