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:
St. John's wort may speed up how quickly your liver processes methadone and oxycodone.
What might happen:
The amount of methadone or oxycodone in your blood may decrease and it may not work as well or you may have symptoms of withdrawal.
What you should do about this interaction:
Let your healthcare professionals (e.g. doctor or pharmacist) know that you are taking these medicines together and if you have any symptoms of withdrawal or if your methadone or oxycodone is not effective for your pain. Let your doctor know if you stop taking St. John's wort. Your doctor may need to change the dose of your medication.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.
1.Eich-Hochli D, Oppliger R, Golay KP, Baumann P, Eap CB. Methadone maintenance treatment and St. John's Wort - a case report. Pharmacopsychiatry 2003 Jan;36(1):35-7.
2.Dolophine (methadone hydrochloride) US prescribing information. Roxane Laboratories, Inc. April, 2015.
3.Nieminen TH, Hagelberg NM, Saari TI, Neuvonen M, Laine K, Neuvonen PJ, Olkkola KT. St John's wort greatly reduces the concentrations of oral oxycodone. Eur J Pain 2010 Sep;14(8):854-9.