Cyclosporine and Fosphenytoin interaction

Cyclosporine and Fosphenytoin: both prescribing labels describe an interaction that usually calls for monitoring, a dose change, or spacing the doses.

Moderate

Usually manageable with monitoring or a dose change. Tell your pharmacist you take both.

What the FDA labels say

From the Cyclosporine (Neoral) label · effective 2026-08-10

Moderate

Drugs/Dietary Supplements That Decrease Cyclosporine Concentrations Antibiotics Anticonvulsants Other Drugs/Dietary Supplements nafcillin carbamazepine bosentan St.

Drug interactionsby drug classView label on DailyMed

From the Fosphenytoin (CEREBYX) label · effective 2025-08-28

Moderate

…the concentration of amprenavir Calcium channel blockers Nifedipine, nimodipine, nisoldipine, verapamil Other Albendazole (decreases active metabolite), chlorpropamide, clozapine, cyclosporine, digoxin, disopyramide, folic acid, methadone, mexiletine, praziquantel, quetiapine 7.3 Hyperammonemia with Concomitant Use of Valproate Concomitant administration of phenytoin…

Drug interactionsnames CyclosporineView label on DailyMed

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Not 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.