Thioridazine/Selected SSRIs; Duloxetine
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:
Severe. These medicines may interact and cause very harmful effects and are usually not taken together. Contact your healthcare professional (e.g. doctor or pharmacist) for more information.
How the interaction occurs:
Some selective serotonin reuptake inhibitors and duloxetine may slow down how quickly your liver processes thioridazine.
What might happen:
The level of thioridazine in your blood may increase. This may increase your risk of an irregular heartbeat, which may be life-threatening.
What you should do about this interaction:
Contact your healthcare professionals (e.g. doctor or pharmacist) right away about takings these medicines together.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.
References:
1.Cymbalta (duloxetine hydrochloride) US prescribing information. Eli Lilly and Company October, 2012.
2.Dear Doctor Letter. Re: Important drug warning about Mellarill. Novartis Pharmaceuticals Corporation July 7, 2000.
3.Thioridazine tablet, US prescribing information. Mylan Pharmaceuticals September, 2010.
4.Sarafem (fluoxetine hydrochloride) US prescribing information. Warner Chilcott April, 2009.
5.Prozac (fluoxetine hydrochloride) US prescribing information. Eli Lilly and Company January, 2013.
6.Symbyax (olanzapine and fluoxetine hydrochloride) US prescribing information. Eli Lilly and Company January, 2013.
7.Luvox (fluvoxamine maleate) US prescribing information. ANI Pharmaceuticals November, 2012.
8.Paxil (paroxetine hydrochloride) US prescribing information. GlaxoSmithKline December, 2012.
9.Pexeva (paroxetine mesylate) US prescribing information. Noven Therapeutics, LLC December, 2012.
10.Carrillo JA, Ramos SI, Herraiz AG, Llerena A, Agundez JA, Berecz R, Duran M, Benitez J. Pharmacokinetic interaction of fluvoxamine and thioridazine in schizophrenic patients. J Clin Psychopharmacol 1999 Dec;19(6):494-9.
11.von Bahr C, Movin G, Nordin C, Liden A, Hammarlund-Udenaes M, Hedberg A, Ring H, Sjoqvist F. Plasma levels of thioridazine and metabolites are influenced by the debrisoquin hydroxylation phenotype. Clin Pharmacol Ther 1991 Mar;49(3):234-40.
12.Hartigan-Go K, Bateman DN, Nyberg G, Martensson E, Thomas SH. Concentration-related pharmacodynamic effects of thioridazine and its metabolites in humans. Clin Pharmacol Ther 1996 Nov;60(5):543-53.
13.Syvalahti EK, Taiminen T, Saarijarvi S, Lehto H, Niemi H, Ahola V, Dahl ML, Salokangas RK. Citalopram causes no significant alterations in plasma neuroleptic levels in schizophrenic patients. J Int Med Res 1997 Jan-Feb; 25(1):24-32.
