Doxazosin and Nifedipine interaction
Doxazosin and Nifedipine: the Nifedipine prescribing label describes an interaction that usually calls for monitoring, a dose change, or spacing the doses.
Usually manageable with monitoring or a dose change. Tell your pharmacist you take both.
What the FDA labels say
From the Nifedipine label · effective 2026-02-05
In the presence of doxazosin, AUC and C max of nifedipine were increased by factors of 1.13 and 1.23, respectively.
Blood pressure should be monitored when doxazosin is co-administered with nifedipine, and dose reduction of nifedipine considered.
Central Alpha1-Blockers Doxazosin: Healthy volunteers participating in a multiple dose doxazosin-nifedipine interaction study received 2 mg doxazosin q.d. alone or combined with 20 mg nifedipine ER b.i.d. Co-administration of nifedipine resulted in a decrease in AUC and C max of doxazosin to 83% and 86% of the values in the absence of nifedipine, respectively.
Compared to nifedipine monotherapy, blood pressure was lower in the presence of doxazosin.
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.