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Verapamil May Increase Bioavailability of Risperidone


In vivo evidence suggests that verapamil may significantly increase the plasma concentration of risperidone (Risperdal—Janssen) due to an increase in bioavailability through P-glycoprotein inhibition.



Nakagami T et al. Effect of verapamil on pharmacokinetics and pharmacodynamics of risperidone: in vivo evidence of involvement of P-glycoprotein in risperidone disposition. Clin Pharmacol Ther. 2005;78:43–51.

Belpomme D et al. Verapamil increases the survival of patients with anthracyclineresistant metastatic breast carcinoma. Ann Oncol. 2000;11:1471–6.

Molento MB et al. Influence of verapamil on the pharmacokinetics of the antiparasitic drugs ivermectin and moxidectin in sheep. Parasitol Res. 2004;92:121–7.

Sadeque AJM et al. Increased drug delivery to the brain by P-glycoprotein inhibition. Clin Pharmacol Ther. 2000;68:231–7.