Cimetidine and Praziquantel interaction
Cimetidine and Praziquantel: the Praziquantel prescribing label flags this combination with the strongest language, such as a contraindication, a boxed warning, or an instruction to avoid it.
Do not combine without a prescriber's guidance. The label language below is the strongest FDA uses.
What the FDA labels say
From the Praziquantel (Biltricide) label · effective 2026-03-02
…outweighs the risks [see Warnings and Precautions ( 5.6 ) and Clinical Pharmacology ( 12.3 ).] 7.2 CYP450 inhibitors Concomitant administration of drugs that decrease the activity of drug metabolizing liver enzymes (CYP450 inhibitors), for example, cimetidine, ketoconazole, itraconazole, erythromycin, and ritonavir may increase plasma concentrations of praziquantel.
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Open in the checkerNot medical advice. Interaction Checker quotes FDA label text and NIH fact sheets. Whether an interaction matters for you depends on doses, timing, kidney and liver function, and other conditions. Confirm with a pharmacist or prescriber.