Medications
SGLT2 Inhibitors (Jardiance, Farxiga) Before Surgery
SGLT2 inhibitors are common diabetes (and heart/kidney) medicines — but they carry one specific surgical risk that makes them stand out: a dangerous ketoacidosis that can happen even with near-normal blood sugar. Because of that, they're usually paused several days before surgery.
Quick answer
Why it matters
SGLT2 inhibitors make your kidneys pass sugar out in the urine. Around surgery — with fasting, the stress of the operation and dehydration — they can push the body into ketoacidosis, a dangerous build-up of acids in the blood.
The catch is that this ketoacidosis can happen while your blood sugar reading is normal or only mildly raised, so it doesn't trigger the usual 'high sugar' alarm and can be missed. That's exactly why these drugs are singled out and stopped a few days before, rather than just on the morning.
These medicines are now also prescribed for heart failure and kidney protection, sometimes in people without diabetes — the same stop-before-surgery advice applies, because the ketoacidosis risk is about the drug, not just the diabetes.
Do not stop without instruction
What to ask your doctor
- Exactly how many days before surgery should I take my last dose?
- How should I manage my blood sugar while the SGLT2 inhibitor is paused?
- When is it safe to restart it after surgery?
- Should I be checking for ketones, and what readings should prompt a call?
Red flags — call your team
Red flags — call your team
- Nausea, vomiting, tummy pain, or feeling unusually unwell or breathless — even if your blood sugar is normal — can be euglycemic DKA: seek urgent medical care
- Fruity-smelling breath, deep or rapid breathing, drowsiness or confusion
- Tell the team you take an SGLT2 inhibitor if you weren't asked — it's easy to overlook
References
- Perioperative and diabetes guidance recommends withholding SGLT2 inhibitors around surgery (commonly the last dose ~3 days before the day of surgery) because of the risk of euglycemic diabetic ketoacidosis; your surgical and diabetes team's instruction takes precedence.
- Applies to empagliflozin (Jardiance), dapagliflozin (Farxiga/Forxiga), canagliflozin (Invokana), ertugliflozin and their combination products.
Frequently asked questions
Why do SGLT2 inhibitors need stopping before surgery when other diabetes pills don't?
Because they carry a specific risk of diabetic ketoacidosis (DKA) that can develop even when blood sugar is normal, which makes it easy to miss. The fasting and stress of surgery increase that risk. Stopping the drug a few days before — usually the last dose about 3 days before your operation — clears it from your system and greatly lowers the danger. Other diabetes medicines are usually just adjusted on the day.
Which medicines are SGLT2 inhibitors?
The generic names end in '-gliflozin': empagliflozin (Jardiance), dapagliflozin (Farxiga or Forxiga), canagliflozin (Invokana) and ertugliflozin, plus combination tablets that contain them (for example with metformin). If you're unsure, check your boxes or ask your pharmacist, and tell your surgical team — these are the ones singled out before surgery.
What is 'euglycemic DKA'?
It's diabetic ketoacidosis — a dangerous build-up of acids (ketones) in the blood — that happens while blood sugar is normal or only slightly raised, rather than very high. Because the usual warning sign of a high sugar reading is absent, it can be missed. The symptoms to watch for are nausea, vomiting, tummy pain, breathlessness or just feeling very unwell, which need urgent care.
When can I restart my SGLT2 inhibitor after surgery?
Usually once you're eating and drinking normally, well hydrated and recovering without complications — your team will give you a specific time. Don't restart it while you're still unwell, not eating properly, or dehydrated, as that's when the ketoacidosis risk is highest. If in doubt, check before resuming.