Cyclophosphamide and Propylthiouracil interaction
Cyclophosphamide and Propylthiouracil: both prescribing labels mention this combination without an instruction to avoid it or change the dose.
Mentioned, no instruction to avoid. Worth knowing; rarely a reason to change anything on its own.
What the FDA labels say
From the Propylthiouracil label · effective 2026-08-25
In some cases, vasculitis resolved/improved with drug discontinuation; however, more severe cases required treatment with additional measures including corticosteroids, immunosuppressant therapy, and plasmapheresis.
From the Cyclophosphamide (Frindovyx) label · effective 2026-08-26
Secondary malignancies (urinary tract cancer, myelodysplasia, acute leukemias, lymphomas, thyroid cancer, and sarcomas) have been reported in patients treated with cyclophosphamide-containing regimens .
Taking more than these two? Interactions stack. Check your whole list at once; it stays in your browser.
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.