Due to the seriousness of the COVID-19 pandemic, Health Canada provided guidance on Canadians' access to controlled substances when needed for medical treatments. As such, prescribers and pharmacists may have to modify care from usual practice. A new protocol was established by META:PHI, CAMH and Ontario Medical Association (OMA) Executive for Addictions Medicine to provide guidance for prescribers. An accompanying guidance document for pharmacists was created by CAMH. Both resources will be updated as circumstances change, and new information becomes available.
Last updated August 2021
Methadone is an opioid medication used to treat severe pain and opioid addiction.
When used to treat severe pain, methadone is available as a tablet or oral solution.
When used to treat opioid addiction, methadone usually comes in the form of a fruit-flavoured drink. The powder is dissolved and taken orally once a day.
Methadone is a long-acting opioid drug used to replace the shorter-acting opioids that someone may be addicted to, such as heroin, oxycodone, fentanyl or hydromorphone. Long-acting means that the drug acts more slowly in the body, for a longer period of time. The effects of methadone last for 24 to 36 hours. In contrast, a person who uses short-acting opioids to avoid withdrawal must use three to four times a day.
When taken at the correct dose, methadone prevents withdrawal symptoms and reduces drug cravings without causing the person to feel high (euphoric) or sleepy. This lowers the harms associated with opioid misuse and gives people who are addicted to opioids a chance to stabilize their lives. This treatment is known as methadone maintenance, which is a type of opioid agonist therapy. Methadone therapy for opioid addiction works similar to buprenorphine, another opioid agonist therapy.
When combined with medical and supportive care, methadone and buprenorphine are equally effective treatments for opioid addiction, although one may work better than the other for some people.
Methadone maintenance is a long-term treatment. The length of treatment varies from one or two years to 20 years or more. However, if the person taking methadone and their doctor agree to end treatment, the methadone dose is tapered down gradually over many weeks or months, easing the process of withdrawal.
Side-effects can include:
Trade names include:
Differences between methadone and buprenorphine include the following:
Mixing methadone or buprenorphine with other drugs that depress the central nervous system can be very dangerous. Avoid other opioids, alcohol and benzodiazepines (e.g., Ativan, Xanax, Restoril, Valium, clonazepam). Taking these is especially risky when you first start opioid agonist therapy. Using other drugs while taking opioid agonist treatment can also cause your dose of methadone to wear off more quickly, meaning you could experience withdrawal.
All opioids have a risk of overdose. The risk is higher with methadone than with buprenorphine. The risk is especially high when you start treatment, and when you stop taking opioids (methadone or other opioids) for a while and then start again. Mixing opioids with other drugs also increases the risk of overdose. If you or someone you know uses opioids, it is a good idea to have a free naloxone kit. Naloxone is a medication that can temporarily reverse the effects of an opioid overdose and allow time for medical help to arrive.
Making the Choice, Making it Work © 2016 Centre for Addiction and Mental Health
Opioid Agonist Therapy: Information for Clients © 2016 Centre for Addiction and Mental Health
Straight Talk: Street Methadone © 2016 Centre for Addiction and Mental Health
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