Health Guides
Sourced, substantial guides on checking interactions, timing, and how to read the evidence behind a result.
How to Check Medication and Supplement Interactions
A practical walkthrough of how to use the checker, read its results, and know what to do when a pair hasn't been reviewed yet.
Last reviewed 2026-08-23
Can You Take Supplements With Prescription Medications?
Why the answer is usually 'it depends on the specific pair' -- and how to find out for a specific combination rather than guessing.
Last reviewed 2026-08-23
Vitamins and Minerals That Can Affect Medication Absorption
How calcium, iron, magnesium, and zinc can bind to certain medications in the gut, and what the reviewed evidence says about spacing doses.
Last reviewed 2026-08-23
Why Timing Matters When Taking Supplements and Medicines
Interaction and timing are different questions -- how spacing, food, and time of day can matter even when there is no direct interaction.
Last reviewed 2026-08-23
Levothyroxine and Supplements: What to Know
Reviewed findings on levothyroxine's sensitivity to timing and specific supplement/medication interactions, sourced from FDA labeling.
Last reviewed 2026-08-23
Warfarin and Supplements: Important Interactions
Why warfarin is especially interaction-sensitive, and the specific, sourced findings currently reviewed for it in our catalog.
Last reviewed 2026-08-23
Antibiotics and Mineral Supplements
How tetracycline-class antibiotics interact with calcium, iron, magnesium, and zinc, and why spacing usually resolves it.
Last reviewed 2026-08-23
Blood Pressure Medicines and Supplements
Potassium-sparing blood pressure medications, potassium supplements, and the reviewed hyperkalemia-risk interaction between them.
Last reviewed 2026-08-23
Can You Take Multiple Supplements at the Same Time?
Supplement-supplement interactions are real too -- what to watch for when stacking several supplements together.
Last reviewed 2026-08-23
What Does “No Documented Interaction Identified” Mean?
A precise explanation of this site's most common result -- what it does and does not tell you about a combination's safety.
Last reviewed 2026-08-23
How We Research Drug–Supplement Interactions
The source hierarchy, review stages, and publishing gate behind every reviewed pair on this site.
Last reviewed 2026-08-23
Questions to Ask Your Pharmacist About Supplements
Specific, useful questions to bring to a pharmacist or clinician about a supplement/medication combination -- and when to ask.
Last reviewed 2026-08-23