Does Nelfinavir Interact with Calcifediol?
CDI records a moderate classification for Nelfinavir and Calcifediol. The stored summary is: CYP3A4 inhibitor may alter serum levels of calcifediol by inhibiting vitamin D metabolism enzymes. Dose adjustment and monitoring of serum 25-hydroxyvitamin D, PTH, and calcium may be required. The mechanism involves inhibition of cyp24a1 and cyp27b1 enzymes involved in vitamin d metabolism. Patients taking both medications should consult their healthcare provider before starting, stopping, or changing the dosage of either drug. This record was extracted from drug labeling through openFDA. NIH/NLM RxNorm is used for drug identities. The summary and severity classification are CDI's processed information, not a verbatim source quotation. Product, route, and patient circumstances matter.
- Severity
- Moderate
- Management
- Monitor for effects
- Data Source
- U.S. FDA via OpenFDA
Recorded Mechanism
Inhibition of CYP24A1 and CYP27B1 enzymes involved in vitamin D metabolism
What To Tell Your Doctor or Pharmacist
If you are taking Nelfinavir and your doctor is considering prescribing Calcifediol (or vice versa), make sure to:
- Inform your doctor and pharmacist of all current medications, including over-the-counter drugs and supplements
- Ask whether the benefits of combining these medications outweigh the risks for your specific situation
- Ask what symptoms to watch for that would indicate the interaction is causing problems
- Ask whether any dosage adjustments are needed
- Never stop or change either medication without first consulting your healthcare provider