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:
Your rifampin may speed up how quickly your liver processes risperidone.
What might happen:
The amount of risperidone 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. Your doctor may want to check the amount of your medicines in your blood. Your doctor may want to change the doses of your medicines. Let your doctor know if you notice any changes in how your medicine is working or any side effects.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.Risperdal Consta (risperidone long acting injection) US prescribing information. Janssen Pharmaceutical Ltd. September, 2011.
2.Mahatthanatrakul W, Nontaput T, Ridtitid W, Wongnawa M, Sunbhanich M. Rifampin, a cytochrome P450 3A inducer, decreases plasma concentrations of antipsychotic risperidone in healthy volunteers. J Clin Pharm Ther 2007 Apr;32(2):161-7.
3.Kim KA, Park PW, Liu KH, Kim KB, Lee HJ, Shin JG, Park JY. Effect of rifampin, an inducer of CYP3A and P-glycoprotein, on the pharmacokinetics of risperidone. J Clin Pharmacol 2008 Jan;48(1):66-72.