Fever and mebendazole
Until July 2024, the Netherlands Pharmacovigilance Centre Lareb received 23 reports of fever following use of mebendazole. Fever is not a known side effect of mebendazole. Fever is mentioned in the product information of mebendazole in several countries.
Mebendazole is an anthelmintic and is indicated for the treatment of infections by worms, such as pinworm and common roundworm. Fever is not a known side effect of mebendazole, but is mentioned in the product information as a symptom of adverse reactions of the skin, such as Steven-Johnson syndrome. Fever is described in different sources from other countries. There is little known about the occurence of fever in relation to the use of mebendazole. Some cases were reported, particularly in those receiving high-dose therapy.
Lareb reports
The Netherlands Pharmacovigilance Centre Lareb has received 23 reports of fever following the use of mebendazole. Fever occurred with a mean time to onset of 1 day after intake of mebendazole. The course of fever was generally mild. Two people were treated with paracetamol. In half of the reports, the person had recovered or was recovering at the time of reporting. Other causes for fever, such as an underlying infection, were not mentioned in the reports.
Fever after use of other anthelmintics
The fever may be caused by a reaction to the killing of the worms by mebendazole. This has also been described with other anthelmintics. Other symptoms that may develop include: skin rash, arthralgia, and swollen lymph nodes.
The Netherlands Pharmacovigilance Centre Lareb has informed the Dutch Medicines Evaluation Board (MEB) about the reports. The MEB asked the Dutch firms to add fever to the product information of mebendazole.