Drug Interaction Checker

Search and add medications to check for known drug-drug interactions with severity ratings.

Checker

Disclaimer: This tool is for informational purposes only. It does not constitute medical advice. Always consult your doctor or pharmacist before making changes to your medication regimen.

How to Use

1
Search for a drug
Type a drug name into the search box. Results appear as you type. Select the drug you want to check.
2
Add more medications
Add at least two medications to your list. You can add up to 10 drugs to check all pairwise interactions.
3
View interactions
Interactions are checked automatically when you have 2 or more drugs. Results show severity level, clinical effect, and management advice.

Search and add medications

Add at least 2 drugs. Maximum 10.

Your medications ()

Checking interactions...

Results

Common combinations to check

About

Drug interactions occur when two or more medications affect each other's pharmacological activity. These interactions can reduce a drug's effectiveness, increase its toxicity, or produce entirely new side effects that neither drug would cause alone. Understanding drug interactions is essential for medication safety.

Pharmacokinetic interactions affect the absorption, distribution, metabolism, or excretion (ADME) of a drug. The most clinically significant involve CYP450 enzymes in the liver. Pharmacodynamic interactions occur when drugs act on the same or related physiological systems. These can be additive, synergistic, or antagonistic.

Always inform your healthcare provider about all medications you take, including over-the-counter drugs, vitamins, and herbal supplements. Drug interaction databases capture documented interactions from FDA labels and clinical studies but cannot predict every possible combination.

FAQ

What is a drug interaction?

A drug interaction occurs when two or more medications affect each other's effectiveness or produce unexpected side effects. Interactions can be pharmacokinetic (affecting how the body processes a drug) or pharmacodynamic (affecting how the drug works at its target site).

What do the severity levels mean?

Major interactions may be life-threatening or require treatment modification. Moderate interactions may worsen a patient's condition and require close monitoring. Minor interactions produce limited clinical effects and are generally manageable with standard care.

Does this tool replace medical advice?

No. This tool is for informational purposes only. It does not constitute medical advice. Always consult your doctor or pharmacist before making changes to your medication regimen. Not all interactions may be listed in our database.

How is the interaction data sourced?

Interactions come from two layers. A curated set covers well-known, clinically significant interactions (such as warfarin with NSAIDs, MAOIs with SSRIs, or ACE inhibitors with potassium-sparing diuretics), described using standard pharmacology references. A second, heuristic layer flags additional potential interactions derived from FDA drug-label warnings (DailyMed, openFDA). All results are informational only and are not a complete list of every possible interaction — always confirm with your doctor or pharmacist.

Can I check supplement and herbal interactions?

Currently, this tool focuses on prescription and over-the-counter drug interactions. Herbal supplements and dietary supplements are not included in our database. Always tell your healthcare provider about all supplements you take, as they can interact with prescription medications.

Medical Disclaimer

This content is for educational and informational purposes only. It is not a substitute for professional medical advice, diagnosis, or treatment. Always consult a qualified healthcare provider before making medication decisions.

Data sources: ChEMBL, PubChem, DailyMed.