Is methadone bad for the heart?

Used appropriately as part of an MMT program, methadone does not appear to directly cause heart problems, even at quite high doses.

There were some concerns during 2001 when LAAM (a long-acting cousin of methadone) was associated with disturbances of normal heartbeat, called cardiac arrhythmias. LAAM was taken off the market in Europe and manufacture of the product in American was discontinued.

To some extent, all opioids, including methadone, have an influence on heart function. Some of these effects are helpful. For example, persons having heart attacks are sometimes given morphine. Other effects, which have been demonstrated mostly in animals or test tube experiments, are less certain as being helpful or harmful. However, methadone has generally not been found to be harmful to heart health in actual patients.

A review panel of MMT medical directors consulted by Addiction Treatment Forum, and collectively representing 117 years of experience in treating more than 29,000 persons with methadone, noted that they had not seen a single heart problem that they would directly attribute to methadone. Similarly, a small study of patients receiving very high doses of methadone – from 500 to 1,400 milligrams per day – did not find any methadone-related heart problems.

This is not to say that MMT patients do not experience heart problems just like other persons. However, the health risks, heart-related and otherwise, for opioid-addicted individuals not in treatment are great and death rates are high. MMT programs, of which methadone is a central part, provide a total healthcare environment potentially contributing to better heart health.

There also is some evidence that methadone maintenance preserves heart health. Having previously observed an absence of cardiovascular disease in MMT patients, a team of New York researchers investigated whether long-term exposure to opioid agents might be associated with decreased severity of coronary artery disease that is believed to precede most myocardial infarctions (heart attacks).

The investigators compared autopsy results in persons who had methadone or opioids in their blood compared with matched decedents (controls) without such drugs present. Severe coronary artery disease (CAD) was found significantly less often in decedents with methadone in their blood than in control-group decedents. In fact, subjects with methadone in their systems were roughly 2½ times less likely to have moderate or severe CAD. Exact reasons for these possible cardioprotective effects of methadone were unclear and require further research. However, the authors concluded that long-term exposure to methadone may lessen CAD severity and its often fatal consequences.