Single low-dose treatment with praziquantel for Diphyllobothrium nihonkaiense infections.

OBJECTIVE

To investigate whether praziquantel is effective against diphyllobothriasis nihonkaiense at doses less than the conventional dose.

PATIENTS AND METHODS

Fourteen Japanese men with diphyllobopthriasis nihonkaiense were treated with a single administration of praziquantel at 5-10 mg/kg.

RESULTS

Twelve patients expelled a complete integrated Diphyllobothrium nihonkaiense with its scolex. One patient expelled an integrated D. nihonkaiense without its scolex, and one patient expelled 2 complete integrated D. nihonkaiense with their scolex, and an integrated D. nihonkaiense without its scolex. The lack of eggs in stool samples was confirmed in these 2 patients after the end of therapy. All patients had not expelled proglottides after the end of therapy for more than 1 year. No side effects were identified in any of the patients.

CONCLUSION

All patients were considered to be cured. Our results indicate that the oral administration of a single dose of praziquantel at 5-10 mg/kg is effective and safe against D. nihonkaiense infections.