Common side effects of methadone treatment
Methadone does come with side effects. Here, Dr. Jana Burson outlines how methadone acts in and on the body. If you have any questions about other side effects of methadone, be sure to send us an email (info [at] addictionblog [dot] org) or respond in the comment section below.
How is methadone absorbed?
Methadone is quickly absorbed from the stomach and intestines, stored in the liver, and released into the bloodstream over time. Plasma levels peak at around two to four hours after dosing.
Opioid tolerance on methadone
Euphoria and drowsiness can be seen if the initial methadone dose is too high, or if the dose has been raised too quickly. Tolerance develops within two weeks to both of these symptoms, and any euphoria felt by the patient subsides. However, patients don’t develop a tolerance to the blocking effects of methadone, meaning that once they get to a stable dose, they do not need to continually increase their dose in order to keep withdrawal symptoms at bay.
The most common side effects of taking methadone include sweating and constipation. All opioids can cause both of these side effects, but methadone is more likely to cause both. Tolerance doesn’t seem to build for this, so these effects usually don’t improve with time.
Methadone effects on the liver
Though stored in the liver, methadone doesn’t damage the liver. Medical illnesses that affect the liver may affect the storage and metabolism of methadone, but methadone will not hasten deterioration of liver function. In fact, there are no serious, long term, adverse effects with indefinite methadone treatment. The most common side effects are sweating, constipation, weight gain, and sexual dysfunction.
Low testosterone and opiates
Methadone causes sexual dysfunction, particularly in men. All opioids, including methadone, suppress testosterone levels. This in turn can decrease sexual desire, and limit the ability to initiate and sustain an erection. Sometimes, as the body adjusts to the presence of a steady level of opioids, testosterone levels may return to normal. If not, some male patients may need to be started on replacement testosterone.
Methadone and weight gain
Many patients on methadone say they crave sweets. Most people do gain weight while on methadone, but the reason isn’t clear. Some of the weight gain may be due to eating more regular meals, and expending less activity to get illicit opioids.
Have you experienced any of these side effects? What other side effects have you heard about from people who are currently taking methadone. And do you know the facts from the myths about methadone maintenance.