Levomethadone; Methadone/Ritonavir 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:
Ritonavir may speed up how quickly your body processes methadone.
What might happen:
The amount of methadone in your blood may decrease and it may not work as well.
What you should do about this interaction:
Let your healthcare professionals (e.g. doctor or pharmacist) know that you are taking these medicines together. If you experience nausea, vomiting, stomach pain, diarrhea, irritability, sleep disturbances, other withdrawal symptoms, or if your methadone is not controlling your pain, contact your healthcare professionals (e.g. doctor or pharmacist). Your doctor may want to adjust the dose of your medicine.Your healthcare professionals 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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- 3.Levopidon (levomethadone) Swedish Summary of Product Characteristics. DNE Pharma AS November 30, 2018.
- 4.Beauverie P, Taburet AM, Dessalles MC, Furlan V, Touzeau D. Therapeutic drug monitoring of methadone in HIV-infected patients receiving protease inhibitors. AIDS 1998 Dec 24;12(18):2510-1.
- 5.Kharasch ED, Bedynek PS, Park S, Whittington D, Walker A, Hoffer C. Mechanism of ritonavir changes in methadone pharmacokinetics and pharmacodynamics: I. Evidence against CYP3A mediation of methadone clearance. Clin Pharmacol Ther 2008 Oct;84(4):497-505.
- 6.Jimenez-Lerma JM, Iraurgi I. Potential opiate withdrawal syndrome after ritonavir administration in a patient treated with methadone. Rev Clin Esp 1999 Mar;199(3):188-9.
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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.