Study supports a flexible approach to methadone dosing

Feb 7 2006

Methadone has been used for more than 30 years as a treatment for heroin addicts. Doctors have all along struggled to find the best doses to help patients overcome their heroin cravings without getting them used to higher levels of methadone (itself an dependence-forming substance) than necessary.

A new study by Jodie Trafton and colleagues (from the VA Palo Alto Health Care System) provides strong support for the notion that there is no one dose that fits all.

Current guidelines recommend methadone doses of at least 60 milligrams (per kilogram bodyweight). However, doctors in methadone clinics report a wide range of doses that are effective, and quite a few clinics treat patients with starting doses that are lower or higher than the recommended amount. Trafton and colleagues studied 222 heroin addicted volunteers who started methadone treatment at 8 different clinics and followed them for up to a year. They examined the range of methadone doses which helped patients achieve heroin abstinence and the factors that influenced whether a particular patient needed a higher or a lower dose.

The range of effective methadone doses (among the 168 patients who achieved abstinence) was very wide, from 1.5 mg to 191.2 mg. 38% of the patients achieved abstinence on less than 60 mg, and 16% of the abstinent patients received a dose of over 100 mg. On the other hand, almost half of the patients who did not achieve heroin abstinence received the recommended dose of 60 mg or more. Overall, patients at clinics that generally adhered to the treatment guidelines (and treated most patients at 60mg or higher) achieved longer periods of abstinence. Among patients who achieved abstinence, higher methadone doses were correlated with posttraumatic stress disorder, depression, a higher number of previous detoxifications from heroin, and some other factors.

These results confirm that effective methadone doses vary very widely. Even high doses that work for one patient do not necessarily work for another, and a substantial percentage of patients achieve abstinence on less than the recommended dose. The study also identifies some factors, such as posttraumatic stress disorder and depression, that seem to influence whether a patient is more likely to need a higher dose. The authors conclude that doctors should work with each patient to find the lowest effective dose for that individual. Because patients in clinics that adhere to the guidelines do better on average, the recommended dose should serve as a starting point that is then adjusted upward or downward.