Levomethadone; Methadone/CYP2B6 Inhibitors Interactions
This information is generalized and not intended as specific medical advice. Consult your healthcare professional before taking or discontinuing any drug or commencing any course of treatment.
Medical warning:
Moderate. These medicines may cause some risk when taken together. Contact your healthcare professional (e.g. doctor or pharmacist) for more information.
How the interaction occurs:
When these two medicines are taken together, your body may not process methadone properly.
What might happen:
The blood levels of levomethadone or methadone may increase and cause more side effects than expected, including:1. High serotonin levels, which may cause changes in body temperature, blood pressure, and behavior or mood, leading to a medical condition called Serotonin Syndrome. Serotonin Syndrome may be life threatening.2. Opioid overdose, including slow/shallow breathing, slow heartbeat, or coma.3. Irregular heartbeat, which can be life-threatening.
What you should do about this interaction:
Your levomethadone or methadone dose may need to be changed if you start or stop taking your other medicine. Let your healthcare professionals (e.g. doctor or pharmacist) know that you are taking both of these medicines.If you experience muscle twitching, tremors, shivering and stiffness, fever, heavy sweating, heart palpitations, restlessness, confusion, agitation, trouble with coordination, or severe diarrhea contact your doctor right away.Ask your doctor or pharmacist if you should have naloxone available to treat opioid overdose. Teach your family or household members about the signs of an opioid overdose and how to treat it. If someone has overdosed and has serious symptoms such as passing out or trouble breathing, give them naloxone if available, then call 911. If the person is awake and has no symptoms, call a poison control center right away. US residents can call their local poison control center at 1-800-222-1222. Canadian residents can call a provincial poison control center. Symptoms of overdose may include: slow/shallow breathing, slow heartbeat, coma.Let your doctor know right away if you notice an irregular heartbeat or have any dizziness or fainting episodes.Your healthcare providers may already be aware of this interaction and may be monitoring you for it. Do not start, stop, or change the dosage of any medicine before checking with them first.
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- 9.This information is based on an extract from the Certara Drug Interaction Database (DIDB) Platform, Copyright Certara 1999-2023..
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CONDITIONS OF USE: The information in this database is intended to supplement, not substitute for, the expertise and judgment of healthcare professionals. The information is not intended to cover all possible uses, directions, precautions, drug interactions or adverse effects, nor should it be construed to indicate that use of a particular drug is safe, appropriate or effective for you or anyone else. A healthcare professional should be consulted before taking any drug, changing any diet or commencing or discontinuing any course of treatment.