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Medication interaction checker
Tick the medicines you take and this flags the combinations that matter most around surgery and anesthesia — so you know what to raise with your team. It's a screening aid, not a complete check, and never a reason to stop a medicine on your own.
Frequently asked questions
Is this a complete drug interaction check?
No — it's a screening aid for the combinations that matter most around surgery and anesthesia. It is deliberately conservative and not exhaustive. Your anesthetist and pharmacist do the full, definitive check against your exact medicines, doses and procedure. Always bring your complete medicine list (including supplements) to your pre-assessment.
What is serotonin syndrome and why does it matter for surgery?
Serotonin syndrome is a dangerous build-up of serotonin that can cause agitation, fast heart rate, high temperature, shivering and muscle stiffness. Several antidepressants combined with certain painkillers used around surgery — especially tramadol, pethidine (meperidine) and the antibiotic linezolid — can trigger it. That's why your team needs to know every antidepressant you take, including St John's Wort.
Should I stop any of these medicines myself?
No. Never start or stop a prescription medicine on your own based on this tool. Some must be continued right up to surgery, some are timed to stop a specific number of days before, and stopping the wrong one (like a blood thinner after a stent, or an antidepressant) can be harmful. Use this to know what to raise — your team makes the plan.
Do supplements really count?
Yes. Fish oil, vitamin E, high-dose garlic, ginkgo and others can add to bleeding risk, and St John's Wort interacts with antidepressants and changes how other drugs are handled. 'Natural' does not mean no interaction — list them too.