Which side effect is associated with methadone?

Prolonged QT interval is a known side effect associated with methadone use. Methadone is an opioid that can affect the heart's electrical system, leading to changes in the heart's rhythm. When the QT interval, which is a measurement of the time it takes for the heart's electrical system to reset after each heartbeat, becomes prolonged, it can increase the risk of serious arrhythmias, such as Torsades de Pointes, which can be potentially life-threatening.

This side effect requires monitoring, especially for patients who may be on other medications that can also prolong the QT interval or those with existing heart conditions. Regular ECG monitoring may be indicated for patients on methadone to ensure that any prolongation is detected early and appropriately managed.

While methadone can also lead to other side effects, such as severe constipation and excessive sedation, these effects are primarily expected effects of opioid therapy rather than specific concerns related to the cardiac effects observed with methadone. Increased heart rate is generally not a typical side effect associated with methadone; rather, it may cause bradycardia (slower heart rate) in some cases. Thus, the correct identification of prolonged QT interval as a side effect is crucial for safe and effective patient