Risperidone/Duloxetine; Fluoxetine; Paroxetine
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:
Duloxetine, fluoxetine, and paroxetine may slow down how quickly your liver processes risperidone.
What might happen:
The amount of risperidone in your blood may increase. This may cause you to have more side effects from your medicine.
What you should do about this interaction:
If you notice any new side effects from your risperidone, or if any side effects become worse, contact your healthcare professional (e.g. doctor or pharmacist). Your doctor may want to check the amount of risperidone in your blood or change the amount of risperidone you take.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.Risperdal Consta (risperidone long acting injection) US prescribing information. Janssen Pharmaceutical Ltd. September, 2011.
2.Spina E, Avenoso A, Scordo MG, Ancione M, Madia A, Gatti G, Perucca E. Inhibition of risperidone metabolism by fluoxetine in patients with schizophrenia: a clinically relevant pharmacokinetic drug interaction. J Clin Psychopharmacol 2002 Aug;22(4):419-23.
3.Bondolfi G, Eap CB, Bertschy G, Zullino D, Vermeulen A, Baumann P. The effect of fluoxetine on the pharmacokinetics and safety of risperidone in psychiatric patients. Pharmacopsychiatry 2002 Mar;35(2):50-6.
4.Spina E, Avenoso A, Facciola G, Scordo MG, Ancione M, Madia A. Plasma concentrations of risperidone and 9-hydroxyrisperidone during combined treatment with paroxetine. Ther Drug Monit 2001 Jun;23(3):223-7.
5.Santoro V, D'Arrigo C, Spina E, Mico U, Muscatello MR, Zoccali R. Effect of adjunctive duloxetine on the plasma concentrations of clozapine, olanzapine, and risperidone in patients with psychotic disorders. J Clin Psychopharmacol 2010 Oct;30(5):634-6.
6.Hendset M, Molden E, Enoksen TB, Refsum H, Hermann M. The effect of coadministration of duloxetine on steady-state serum concentration of risperidone and aripiprazole: a study based on therapeutic drug monitoring data. Ther Drug Monit 2010 Dec;32(6):787-90.





