Mexiletine; Propafenone/Rifamycins
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 your heart medicine properly.
What might happen:
The blood levels of your heart medicine may decrease and cause problems with your heart rate.
What you should do about this interaction:
If you experience a fast or irregular heartbeat, contact your doctor. Your doctor may need to adjust the dose of your heart medicine.Your healthcare professionals (e.g. doctor or pharmacist) may already be aware of this drug interaction and may be monitoring you for it. Do not start, stop, or change the dosage of any medicine before checking with them first.
References:
1.Pentikainen PJ, Koivula IH, Hiltunen HA. Effect of rifampicin treatment on the kinetics of mexiletine. Eur J Clin Pharmacol 1982;23(3):261-6.
2.Rythmol (propafenone hydrochloride) US prescribing information. Abbott Laboratories March, 2013.
3.Dilger K, Hofmann U, Klotz U. Enzyme induction in the elderly: effect of rifampin on the pharmacokinetics and pharmacodynamics of propafenone. Clin Pharmacol Ther 2000 May;67(5):512-20.
4.Dilger K, Greiner B, Fromm MF, Hofmann U, Kroemer HK, Eichelbaum M. Consequences of rifampicin treatment on propafenone disposition in extensive and poor metabolizers of CYP2D6. Pharmacogenetics 1999 Oct; 9(5):551-9.
