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Michael E. Seem, MD

Preparing for Surgery · No. 3

Medication Instructions Before Surgery.

Several common medications affect bleeding, healing, or anesthesia. This sheet explains the categories, your specific stop-and-restart instructions come from the surgical team and your prescribers.

The one rule that matters most

Never stop a prescribed medication on your own
Especially blood thinners, heart medications, and diabetes medications. Stopping some of these without a plan is more dangerous than the surgery itself. Every stop-and-restart decision is made with the prescribing clinician.

Bring a complete list

Include prescriptions, over-the-counter medicines, vitamins, and supplements, with doses. Supplements matter — several affect bleeding and interact with anesthesia.

Categories we will review with you

CategoryExamplesWhy it matters
Blood thinnersWarfarin, apixaban, rivaroxaban, clopidogrel Timing is coordinated with your prescriber — individualized, never one-size-fits-all
NSAIDsIbuprofen, naproxen, aspirin products Can increase bleeding; you will receive specific guidance on when to pause
Diabetes medicationsInsulin, metformin, GLP-1 agonists Doses often change around fasting and surgery day; GLP-1 timing affects anesthesia
Immune-modifying drugsRheumatoid/psoriasis biologics, steroids May affect infection risk and healing; coordinated with your rheumatologist
Supplements & herbalsFish oil, vitamin E, ginkgo, turmeric Several increase bleeding risk and should be reviewed individually
Weight-loss / GLP-1 injectionsSemaglutide, tirzepatide Tell us — these change fasting requirements for anesthesia safety

Surgery-day medications

At your pre-operative visit you will receive a written list of exactly which medications to take with a sip of water on the morning of surgery, and which to hold. The facility’s instructions are always the ones to follow — keep them with this sheet.

What happens next

Questions about your visit or your recovery?