Higher than recommended doses of the diarrhoea medicine loperamide (imodium) has been linked to serious cardiac events, the FDA warns.

The majority of the 48 reported cardiac adverse events occurred in individuals who were intentionally misusing and abusing high doses of loperamide in attempts to self-treat opioid withdrawal symptoms or to achieve a feeling of euphoria the agency said in a Drug Safety Communication.

Clinicians should consider loperamide as a possible cause of unexplained cardiac events including QT interval prolongation, Torsades de Pointes or other ventricular arrhythmias, syncope, and cardiac arrest.

Patients should be advised that taking loperamide to follow the dosing recommendations on the label because taking higher than recommended doses, either intentionally or unintentionally, may lead to abnormal heart rhythms and serious cardiac events leading to death.