Calcium and Iron
Supplement–drug interaction evidence from the TruthStack database.
| Severity | HIGH |
|---|---|
| Evidence Tier | Moderate |
| Interaction Type | ABSORPTION INTERFERENCE |
| Mechanism | pharmacokinetic |
| Last Reviewed | 2026-02-07 |
Summary
{'primary': 'Separate Ca and Fe supplements by 2-4 hours', 'timing': 'Take iron AM on empty stomach; calcium PM with food', 'exception': 'Single-meal calcium (<50mg) has minimal effect'} Discuss with your prescriber or pharmacist.
API Reference
GET https://api.truthstack.co/v1/check?c1=calcium&c2=iron
Open, unauthenticated. Returns JSON. Developer documentation
Related Interactions
What this page is and is not. TruthStack is an informational reference database that describes published pharmacological findings. It does not provide medical advice, diagnosis, or treatment recommendations. The information on this page reflects flags in our database and should not replace consultation with a qualified healthcare provider. Always discuss supplement-drug combinations with your prescriber or pharmacist.