Is Calcium Safe with Verapamil?
Free · No account · based on published sources including NIH ODS, FDA drug labels, and peer-reviewed literature
Do not abruptly start or stop high-dose calcium supplements while on verapamil. Discuss with your doctor before taking calcium supplements above 500 mg/day. Monitor blood pressure for signs of reduced drug efficacy.
Why this interaction occurs
High-dose calcium supplementation may competitively antagonize verapamil's mechanism of action by increasing extracellular calcium concentrations, potentially reducing its antihypertensive and antiarrhythmic efficacy. This interaction is more clinically relevant with verapamil due to its strong calcium channel blockade.
Evidence
Evidence level: limited.
Reported safety data
The FDA’s adverse event reporting system (FAERS) has received 41,693 reports mentioning Verapamil. This reflects reported cases involving the medication in general — not confirmed causation, and not specific to the Verapamil + supplement combination on this page.
FAERS reports are voluntary and cannot prove that a drug caused an event. Do not use report counts to assess the safety of this specific drug-supplement pair.
Frequently asked questions
Related interactions
All Calcium interactions → · All Verapamil interactions →
Already checked this one — check your whole list
Educational only — not medical advice.
Always confirm with your doctor or pharmacist.