Medications and Anaesthesia
Before your surgery or procedure, some medicines may need to be stopped or reviewed by your anaesthetist, GP or another medical specialist. At your pre-operative consultation, please tell your anaesthetist about every medication you are taking or have recently taken — including anything you buy without a prescription.
10–14 days before surgery
The following medicines need to be reviewed at least 10 days before surgery. Many can be continued through the operative period, but this depends on the nature of the operation and your individual circumstances.
Pain relief and anti-inflammatories
- Aspirin (low-dose aspirin — Astrix, Cardiprin, Cartia, DBL Aspirin, Solprin)
Aspirin used to be stopped before surgery as a matter of course. That is no longer the general rule, and it can be continued in most cases. As a precaution, please discuss continuing or stopping it with your GP, anaesthetist or surgeon.
Aspirin is also an ingredient in many other medicines, including some for coughs and colds. If in doubt, read the product labelling or ask a pharmacist.
- Piroxicam (Candyl, DBL Piroxicam, Feldene, Mobilis, Rosig, Pirohexal)
- Tenoxicam (Tilcotil)
- Clopidogrel (Iscover, Plavix)
If you take clopidogrel, it needs to be reviewed before your operation. The decision to stop or continue is made on an individual basis, so please review this medication with your anaesthetist, GP or other medical specialist at least 10 days before surgery.
- Natural health or herbal medicines
These need to be stopped 7–14 days before surgery. Some herbal medicines may be unsafe before surgery, including echinacea, ephedra, garlic, gingko, ginseng, kava, St John’s wort and valerian.
Paracetamol (Panadol) can be continued without interruption.
Three days before surgery
The following should generally be stopped at least 3 days before surgery:
Anti-inflammatories
- Diclofenac (Arthrotec, Diclohexal, Dinac, Fenac, Voltaren)
- Diflunisal (Dolobid)
- Ibuprofen (Act 3, Nurofen, Brufen, generic ibuprofen, Rafen, Triprofen, Actiprofen)
- Indometacin (Arthrexin, Indocid, Indospray)
- Ketoprofen (Orudis, Oruvail, Orudis Gel)
- Ketorolac (Toradol)
- Mefenamic acid (Mefic, Ponstan)
- Naproxen (Inza, Proxen, Naprosyn)
- Naproxen sodium (Aleve, Anaprox, Crysanol, Naprogesic, generic naproxen)
- Sulindac (Aclin, Clinoril)
- Tiaprofenic acid (Surgam)
Warfarin (Coumadin, Marevan)
- Warfarin needs to be stopped before nearly all surgery (cataract surgery is the usual exception). Please organise this well before your operation, with your surgeon and prescribing doctor involved in planning it. Injections may be needed to replace the warfarin during the peri-operative period.
The day of surgery
Medicines to speak to your anaesthetist and surgeon about:
- Aspirin (low-dose aspirin — Astrix, Cardiprin, Cartia, DBL Aspirin, Solprin)
- Clopidogrel (Iscover, Plavix)
- Accutane (isotretinoin)
- Dipyridamole (Asasantin, Persantin)
- Diabetes medication and insulin
You will almost certainly need to fast on the day of surgery, and this affects how your diabetes is managed, whatever its type. Please discuss any change to your diabetes medication with your diabetes specialist, anaesthetist or GP before the day of surgery.
GLP-1 medications for diabetes or weight loss
These medicines are also known as GLP-1 receptor agonists and dual GLP-1/GIP receptor co-agonists. They include:
- Ozempic and Wegovy (semaglutide)
- Saxenda and Victoza (liraglutide)
- Trulicity (dulaglutide)
- Mounjaro (tirzepatide)
Please tell your anaesthetist if you take one of these medicines, whether it was prescribed for diabetes or for weight loss.
These medicines slow the rate at which the stomach empties, so food and drink can still be in your stomach at the time of your anaesthetic even after a normal fast. That is unsafe, because stomach contents can come back up into your mouth during a procedure.
Current advice from the Australian and New Zealand College of Anaesthetists is to keep taking your medication as you normally would — it does not need to be stopped before surgery. What changes instead is how you prepare your stomach, starting the day before your procedure. Our fasting guidelines set out what this involves.
If you have diabetes (particularly if you take insulin), or you are having bowel preparation for a colonoscopy or barium enema, please ask your doctor for instructions specific to you.
Take all other medicines as prescribed, unless your doctor advises otherwise.
- Bringing a written list of your medications with you — including doses and timing — is a real help, and makes it easier to manage your treatment before, during and after your operation.
If you have any questions or concerns about your medications, please contact us — we are glad to help.
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