Registered Nurses' Association of Ontario

Administration of MMT - Tips for Ensuring Right Dose When Administering Methadone

  • Prior to administering methadone, the nurse must accurately assess the client for signs and symptoms of intoxication.
  • If the client is found to be intoxicated, methadone should be deferred until the client has been reassessed by the physician. It is safer to refuse or delay administering methadone in an intoxicated client if other drugs have been consumed. Opioid withdrawal in an adult is not life threatening, but combining methadone and other sedatives may be.
  • The nurse must be able to verify when the last dose of methadone was given in order to safely administer the next dose. This is especially important when the client is transferred from one dispensary to another.
  • The nurse must follow clinic policy if consecutive doses are missed prior to administering methadone. The College of Physicians and Surgeons of Ontario (CPSO) guidelines recommend giving the client their prescribed dose of methadone, provided they are not intoxicated if they have missed one or two days. If the client misses three consecutive days, the CPSO guidelines recommend that clients are assessed by the prescribing physician prior to receiving their next dose. The nurse must document missed doses and refer clients for physician assessment when needed.
  • The nurse should verify with the client what their dose of methadone is and compare it to the dose on the container as they are verifying the client’s identity.
  • Dose increases outside of the CPSO guidelines should be verified with the physician to ensure an error has not occurred.


Summary of recommendations for management of the early stabilization phase:


The recommended initial daily dose is 10-30 mg.

Consider starting at a lower dose (10-20 mg) for the following client groups:


  • The elderly with underlying respiratory disease.
  • Users of sedation drugs or drugs that inhibit methadone metabolism.
  • Those with lower opioid tolerance e.g. non-daily opioid use, daily use of codeine, or moderate use of oral opioids.
  • The recently abstinent with negative urine screens (initiate at 5-10 mg).
  • Start at a lower methadone dose if history or urine drug screen suggests recent use of benzodiazepines, alcohol or other sedating drugs.


Summary of recommendations for dosage adjustment during the late stabilization and maintenance phases:

  • Doses should only be increased after the physician has assessed the client and determined that the client has symptoms of withdrawal, ongoing opioid use or cravings.
  • During the late stabilization phase, doses should be increased by no more than 5-15 mg every three to four days. Extra caution is advised for high-risk clients.
  • During the maintenance phase, or if the dose is 80 mg or higher, the dose should be increased by no more than 5-10 mg every five to 14 days.
  • For most clients, the optimal dose is between 50-120 mg.
Addiction and Mental Health
Supporting Clients on Methadone Maintenance Treatment
Point of Care Resources