The European Medicines Agency’s safety committee (PRAC) has recommended that all medicines containing levamisole be withdrawn from the EU market. 

 

The decision follows an EU-wide review concluding that “the benefits of these medicines no longer outweigh their risks for the treatment of parasitic worm infections in adults and children.”

 

The review confirmed that leukoencephalopathy, a rare but serious side effect, can be triggered by levamisole. This condition “damages the white matter of the brain, which is made of nerve fibres covered by myelin, a protective layer that allows efficient communication between different parts of the brain.” It can be debilitating and life-threatening, especially if left untreated, and diagnosing it is complex.

 

PRAC’s findings show that “leukoencephalopathy can occur after a single dose of levamisole and that symptoms may develop up to several months after treatment.” 

 

The committee noted that “the review did not identify any measures to reduce the risk or any group of people who may be at higher or lower risk.” With other medicines available in the EU for parasitic worm infections, PRAC concluded that “the benefits of levamisole medicines no longer outweigh the risks and recommended that their marketing authorisations be withdrawn in the EU.”

 

The recommendation is based on new data from continuous safety monitoring of medicines in the EU, including reports of “serious cases of leukoencephalopathy and demyelination of the central nervous system (loss of myelin in the brain and spinal cord) following use of levamisole,” scientific literature, and advice from independent experts in infectious diseases, neurology, and the World Health Organization.

 

The EMA emphasized that it “continuously monitors the safety of medicines authorised in the EU. When new evidence shows that a medicine’s risks may outweigh its benefits, the Agency acts to protect public health.”

 

Patients who have taken levamisole should seek medical advice immediately if they experience “muscle weakness, difficulty speaking, confusion or difficulty controlling movements,” as symptoms can appear even after a single dose and may take months to manifest.

 

For healthcare professionals, PRAC stressed that “neurologic symptoms vary depending on the localisation of the lesions and may include muscular weakness, language impairment, cognitive dysfunction, ataxia and paresis.” Alternative treatments for parasitic worm infections are available across the EU.