Methadone induced torsade de pointes in a patient receiving antiretroviral therapy.

St James's Hospital, Dublin.
Irish medical journal (Impact Factor: 0.51). 100(10):631-2.
Source: PubMed


Adverse drug reactions account for approximately 5% of acute medical admissions. A 34-year-old male patient receiving antiretroviral therapy, methadone and flurazepam presented to the emergency room following collapse with associated loss of consciousness. Cardiac monitoring demonstrated marked Q-T prolongation followed by the cardiac arrhythmia, torsade de pointes. The patient made a full recovery following withdrawal of the antiretroviral therapy and a reduction in methadone dose. Methadone is a recognised cause of this potentially fatal cardiac arrhythmia which is more likely to occur when methadone metabolism is inhibited by drugs such as HIV tease inhibitors.

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