Free Tool
Supplement Interaction Checker
Add the supplements and medications you're taking. We'll check them against a curated database of 105 documented interactions — including dangerous combinations, absorption conflicts, timing issues, and beneficial synergies. Every entry has a cited source.
Your list
Add two or more substances below to check for interactions.
Add at least two items to see interactions.
Popular pairs
What we track
- danger
- 18
- warning
- 22
- caution
- 32
- synergy
- 27
- info
- 6
Formulate surfaces the same interaction intelligence inside the desktop app so you can see warnings on every stack change. Get the desktop app →
Medical disclaimer. This tool is for educational purposes only and does not replace advice from a qualified healthcare provider. Always consult your prescriber before combining supplements with prescription medication.