MyStaq

Interaction Checker

What you take, checked against everything else you take.

Add your supplements and your medications. We'll flag where they interact, explain why, and tell you what to do about it.

What we check

  • Supplement + supplement — iron and calcium, zinc and copper, timing conflicts
  • Supplement + medication — the ones most people never get told about

What we don't check

Medication + medication. Your pharmacist and your prescriber already screen for those, and they have your full record. We focus on the gap nobody covers: what happens when supplements meet prescriptions.

Free. No account. Nothing about your list is sold or used for advertising.

Interaction Checker

Interaction Checker

Check your supplements and medications

Add your supplements and the medications you take. We'll check each supplement against each medication, and your supplements against each other.

The medications and supplements you enter are used only to build this report. They are not stored or linked to you. Learn more

Don't see something you take? Our database is always growing — this isn't an exhaustive list, so always confirm with your pharmacist or doctor even if nothing is flagged.

Start with at least one supplement, then add any medications you take.

Clinical elements

Interaction guides

Longer reads on the pairs people ask about most, each reviewed by our medical reviewer.

+ 6 more guides

Birth Control and St John's WortBerberine and MetforminBerberine and Ozempic (GLP-1s)Levothyroxine and IronInositol and MetforminSpironolactone and Spearmint

PCOS medication checks

Taking something for PCOS?

These are the combinations we get asked about most. Explore a pair, then add it to your check above, or add your PCOS medications in one go.

Common PCOS medications

More combinations and safety checks

MetforminVitamin B12

Worth knowing · Your medication may be using this up

What happens

Metformin can lower your B12 over time. Low B12 shows up as tiredness, tingling in your hands or feet, or brain fog. These are all easy to blame on PCOS itself.

What to do

Ask for a B12 level at your next blood draw, and supplement if it comes back low. If you've been on metformin four years or more, ask for it yearly.

Source: FDA metformin prescribing information; NIH Office of Dietary Supplements, Vitamin B12

Last reviewed: July 2026

Educational, not medical advice. Don't stop or change a prescription without talking to your prescriber.

Not sure which type of PCOS you have? Find your type

This tool is for information, not medical advice. It doesn't check medication–medication interactions, doesn't know your full history, lab results, or doses, and can't replace your prescriber or pharmacist. Don't start, stop, or change anything you take based on what you see here.

Sources: NIH Office of Dietary Supplements, NCCIH, Memorial Sloan Kettering About Herbs, FDA.

Medically reviewed by Dr Zainab Ajmal · Last reviewed July 2026

Sources

NIH-ODSNIH Office of Dietary Supplements
NIH-NCCIHNIH National Center for Complementary and Integrative Health
MSK-AHMemorial Sloan Kettering About Herbs database
FDA-DSCFDA Drug Safety Communications
DRUGSDrugs.com clinical interaction database
AHAAmerican Heart Association