From the Guidelines
You should take only the medications specifically approved by your anesthesiologist or surgeon on the morning of surgery. Typically, essential medications that are usually continued include blood pressure medications (such as lisinopril, metoprolol, or amlodipine) 1, seizure medications (like levetiracetam or lamotrigine), thyroid medications (such as levothyroxine), and Parkinson's disease medications. These should be taken with just a small sip of water. However, you should generally avoid taking diabetes medications (including insulin and oral medications like metformin) 1, diuretics (water pills like hydrochlorothiazide), and blood thinners (such as warfarin, apixaban, or clopidogrel) 1 unless specifically instructed otherwise.
The reason for continuing certain medications is to prevent dangerous fluctuations in vital functions during surgery, while others are stopped to reduce risks of hypoglycemia, dehydration, or excessive bleeding. For example, metformin should be held on the day of surgery 1, and SGLT2 inhibitors should be discontinued 3–4 days before surgery 1. Other oral glucose-lowering agents should be held the morning of surgery or procedure 1.
It's also important to note that antihypertensive therapy should be continued up to the morning of surgery and restarted promptly in the post-operative period 1. However, consideration should be given to withholding ACE inhibitors and angiotensin receptor antagonists the morning of surgery to decrease the risk of perioperative renal dysfunction 1. Always follow your specific pre-operative instructions, as individual circumstances may require different approaches, and inform your surgical team about all medications you regularly take.
Some key points to consider:
- Continue essential medications like blood pressure medications and seizure medications
- Avoid taking diabetes medications, diuretics, and blood thinners unless specifically instructed otherwise
- Follow specific pre-operative instructions and inform your surgical team about all medications you regularly take
- Consider withholding ACE inhibitors and angiotensin receptor antagonists the morning of surgery to decrease the risk of perioperative renal dysfunction 1
From the FDA Drug Label
The FDA drug label does not answer the question.
From the Research
Medications to be Taken on the Morning of Surgery
The following medications can be considered for continuation on the morning of surgery:
- Antiplatelet drugs, such as aspirin and clopidogrel, can be continued in most cases, except when bleeding may occur in closed spaces or where excessive blood loss is expected 2
- Patients taking nonsteroidal anti-inflammatory drugs (NSAIDs) should stop taking them in time to allow elimination of the drug, or use drugs with short half-lives 3
- Sodium-glucose cotransporter 2 inhibitors (SGLT2i) should be held for at least 3-to-4 days preoperatively, according to Food and Drug Administration guidelines 4
- Oral anticoagulants and antiplatelet medications require careful management, and surgery is delayed when possible, with attention paid to exercising meticulous techniques and treating coexisting issues 5
- Most neurologic medications appear safe to continue until the morning of surgery, but consultation with a neurologist may be necessary to ensure patient safety 6
Medications to be Discontinued Before Surgery
The following medications may need to be discontinued before surgery:
- Clopidogrel should not be discontinued before a noncardiac procedure, unless vital, and should be resumed within 12-24 hours after the operation 2
- NSAIDs with half-lives longer than 6 hours should be discontinued before elective surgery 3
- SGLT2i should be held for at least 3-to-4 days preoperatively, according to Food and Drug Administration guidelines 4
- Oral anticoagulants and antiplatelet medications may require reversal agents or platelet transfusion before emergency cardiac surgery 5