Serious. These medicines may interact and cause very harmful effects. Contact your healthcare professional (e.g. doctor or pharmacist) for more information.
How the interaction occurs:
When haloperidol and pimozide are taken with quinupristin-dalfopristin, your body may process haloperidol and pimozide more slowly.
What might happen:
Your blood levels of haloperidol or pimozide may increase. This may result in an irregular heartbeat, which may be life threatening.
What you should do about this interaction:
Contact your healthcare professionals (e.g. doctor or pharmacist) as soon as possible about taking these two medicines together. They may already be aware of this drug interaction and may be monitoring you for it. Do not stop, start, or change the dosage of any medicine before checking with them first.
1.Synercid (quinupristin-dalfopristin) US prescribing information. Rhone-Poulenc Rorer Pharmaceuticals, Inc. September 21, 1999.
2.Drew BJ, Ackerman MJ, Funk M, Gibler WB, Kligfield P, Menon V, Philippides GJ, Roden DM, Zareba W. Prevention of torsade de pointes in hospital settings: a scientific statement from the American Heart Association and the American College of Cardiology Foundation. J Am Coll Cardiol 2010 Mar 2;55(9):934-47.