Your usual medicines may need to be adjusted before surgery to keep you safe. Always bring your medicines (or a complete list) to hospital, including tablets, inhalers, patches, and injections. Below is a guide to common medicines.
If you are unsure about any drug, ask!
Your usual medicines may need to be adjusted before surgery to keep you safe. Always bring your medicines (or a complete list) to hospital, including tablets, inhalers, patches, and injections. Below is a guide to common medicines.
If you are unsure about any drug, ask!
Blood Pressure Medicines
ACE Inhibitors and ARBs
Examples: perindopril (Coversyl®), ramipril (Tritace®), lisinopril (Zestril®), irbesartan (Avapro®), valsartan (Diovan®), candesartan (Atacand®), telmisartan (Micardis®), losartan (Cozaar®).
Instruction: Withhold for 24 hours before surgery (do not take on the morning of surgery).
Beta-blockers
Examples: atenolol (Tenormin®), metoprolol (Betaloc®, Lopresor®), bisoprolol (Bicor®), propranolol (Inderal®).
Instruction: Continue as normal, including the morning of surgery.
Calcium channel blockers
Examples: amlodipine (Norvasc®), diltiazem (Cardizem®), verapamil (Isoptin®).
Instruction: Continue as normal.
Diuretics
Examples: frusemide (Lasix®), hydrochlorothiazide, indapamide (Natrilix®), spironolactone (Aldactone®).
Instruction: Withhold on the morning of surgery to reduce dehydration/low blood pressure.
Blood Thinners
Warfarin (Coumadin®, Marevan®)
Usually stopped 5 days before surgery. May need “bridging” with injections.
Direct Oral Anticoagulants (DOACs)
Examples: apixaban (Eliquis®), rivaroxaban (Xarelto®), dabigatran (Pradaxa®), edoxaban (Lixiana®).
Usually stopped 2–3 days before surgery (longer if kidney function is reduced).
Antiplatelets
Examples: clopidogrel (Plavix®), ticagrelor (Brilinta®), prasugrel (Effient®).
Usually stopped 5–7 days before surgery.
Aspirin (Cartia®, Astrix®) → Continued
Diabetes Medicines
Diabetes medicines and insulin before surgery
These are general instructions for adults having surgery or a procedure with sedation or anaesthesia. Please follow any specific instructions given to you by your anaesthetist, surgeon, pre-admission clinic, GP, endocrinologist or diabetes educator.
If you have type 1 diabetes, use an insulin pump, have frequent low blood glucose, or have unstable diabetes control, please contact us before surgery for an individual plan.
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Diabetes tablets
Take your usual diabetes tablets up to and including the night before surgery, unless you have been told otherwise.
Do not take diabetes tablets on the day of surgery.
Restart them when you are eating and drinking normally, unless you have been told otherwise.
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SGLT2 inhibitors / “flozins”
Some diabetes, heart failure and kidney medicines need to be stopped earlier because they can increase the risk of ketoacidosis around surgery. This can occur even when the blood glucose level is not very high.
Stop SGLT2 inhibitors for 3 days before your procedure. This means do not take them on the two days before surgery or on the day of surgery.
For example, if your surgery is on Friday, your last dose should be on Tuesday.
Examples include:
Jardiance, Forxiga, Steglatro, Xigduo/Xigduo XR, Jardiamet, Glyxambi, Qtern/Qternmet, Segluromet and Steglujan.
Do not restart an SGLT2 inhibitor until you are eating and drinking normally and are not unwell. Ask for advice before restarting if you have nausea, vomiting, abdominal pain, infection, dehydration or ketones.
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Short-acting or meal-time insulin
Do not take short-acting or meal-time insulin while fasting, unless you have been given a specific correction-dose plan.
Examples include:
NovoRapid, Fiasp, Humalog, Apidra and Actrapid.
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Long-acting basal insulin
Do not stop basal insulin completely unless you have been specifically told to do so.
If you take long-acting basal insulin, take 50% of your usual dose at the usual time from the evening before surgery until your procedure, unless you have been given different instructions.
Examples include:
Optisulin/Lantus, Toujeo, Tresiba, Levemir and Semglee.
For example, if you normally take 20 units, take 10 units.
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Intermediate-acting insulin
If you take intermediate-acting insulin, such as Protaphane or Humulin NPH, take 50% of your usual dose at the usual time, unless you have been given different instructions.
Premixed insulin and Ryzodeg
Premixed insulin and co-formulated insulin contain both a meal-time insulin component and a longer-acting insulin component. This means the dose needs to be adjusted when you are fasting.
Examples include:
NovoMix 30, Ryzodeg 70/30, Humalog Mix, Mixtard 30/70 and Humulin 30/70.
The evening before surgery (Intermediate-acting insulin only)
Take 80% of your usual evening dose.
For example, if you normally take 30 units in the evening, take 24 units.
Morning surgery — procedure before 1 pm (Intermediate-acting insulin only)
Do not take your morning premixed insulin or Ryzodeg while you are fasting.
Check your blood glucose level when you wake up and bring your insulin and glucose monitor with you to hospital.
Your insulin will be restarted after surgery when you are eating and drinking safely.
Afternoon surgery — procedure after 1 pm (Intermediate-acting insulin only)
Have an early light breakfast as instructed by the hospital.
Take 50% of your usual morning dose of premixed insulin or Ryzodeg with breakfast.
For example, if you normally take 30 units in the morning, take 15 units.
After breakfast, do not take any more premixed insulin, Ryzodeg or meal-time insulin while you are fasting.
Check your blood glucose level when you wake up and bring your insulin and glucose monitor with you to hospital.
Lunchtime dose (Intermediate-acting insulin only)
If you normally take a lunchtime dose, do not take it while fasting unless you have been given different instructions.
After surgery (Intermediate-acting insulin only)
Restart your usual insulin routine when you are eating and drinking normally, unless your anaesthetist, surgeon, pre-admission clinic or diabetes team gives you different instructions.
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Insulin pumps
Do not stop or suspend an insulin pump unless you have been given an alternative insulin plan.
Please contact us before surgery for specific pump instructions.
Cholesterol Medicines
Statins
Examples: atorvastatin (Lipitor®), rosuvastatin (Crestor®), simvastatin (Zocor®), pravastatin (Pravachol®).
Instruction: Continue as normal.
Other cholesterol-lowering drugs
Ezetimibe (Ezetrol®), fenofibrate (Lipanthyl®). → Continue.
Antidepressants and anti-anxiety medicines
Examples: sertraline (Zoloft®), escitalopram (Lexapro®), venlafaxine (Efexor®), amitriptyline (Endep®).
Instruction: Continue.
Epilepsy medicines
Examples: valproate (Epilim®), carbamazepine (Tegretol®), levetiracetam (Keppra®).
Instruction: Continue.
Inhalers for asthma/COPD
Examples: Ventolin®, Seretide®, Spiriva®.
Instruction: Continue and bring them to hospital.
Steroids
Examples: prednisone, dexmethasone, hydrocortisone.
Instruction: Do not stop suddenly. You may need extra “stress doses” during surgery.
Pain medicines
Paracetamol: continue as normal.
Anti-inflammatories (NSAIDs): (Nurofen®, Voltaren®, Mobic®) - stopped before surgery due to bleeding/kidney risk.
Opioids (Endone®, Targin®, Tramadol®): continue if prescribed.
Supplements and herbal remedies
Fish oil, vitamin E, garlic, ginkgo, ginseng, St John’s Wort: stop at least 7 days before surgery.
Ozempic, Wegovy, Mounjaro, Trulicity etc
If you are taking Ozempic, Wegovy, Mounjaro, Trulicity or similar medications before surgery, you will need to follow special fasting rules.
- 24–6 hours before surgery: clear fluids only.
- 6–2 hours before: water only (max 200 ml per hr).
- 2 hours before: nothing by mouth.
Clear fluids include water, black tea/coffee (no milk), clear apple juice, electrolyte drinks, or clear broth. Avoid milk, smoothies, protein shakes, creamy soups, or juices with pulp.
If you did not follow these instructions, please tell me - your surgery may be delayed or modified.
Some conditions (e.g. gastroparesis, Parkinson’s, bowel problems) may also slow stomach emptying, even with correct fasting. Please let your me know.
©EJHalvey FANZCA
Blood Pressure Medicines
ACE Inhibitors and ARBs
Examples: perindopril (Coversyl®), ramipril (Tritace®), lisinopril (Zestril®), irbesartan (Avapro®), valsartan (Diovan®), candesartan (Atacand®), telmisartan (Micardis®), losartan (Cozaar®).
Instruction: Withhold for 24 hours before surgery (do not take on the morning of surgery).
Beta-blockers
Examples: atenolol (Tenormin®), metoprolol (Betaloc®, Lopresor®), bisoprolol (Bicor®), propranolol (Inderal®).
Instruction: Continue as normal, including the morning of surgery.
Calcium channel blockers
Examples: amlodipine (Norvasc®), diltiazem (Cardizem®), verapamil (Isoptin®).
Instruction: Continue as normal.
Diuretics
Examples: frusemide (Lasix®), hydrochlorothiazide, indapamide (Natrilix®), spironolactone (Aldactone®).
Instruction: Withhold on the morning of surgery to reduce dehydration/low blood pressure.