Patients with Diabetes, on Tablets or Non-insulin Injections, Undergoing Surgery
You are due to have an operation which will mean that you will be asked to omit at least one meal. This leaflet gives advice about what you should do about your diabetes treatment before and after the surgery.
Before your operation, please follow the instructions below.
If your operation is in the morning
- Do not take any food or drink other than water from six hours before the time you are asked to come to hospital
- You may drink water until two hours before you come to hospital.
If your operation is in the afternoon
- Eat breakfast before 7am and take no food or drink other than water after this time
- You may drink water until two hours before you come to hospital
If you are on tablets like Gliclazide, Glipizide, Glibenclamide, Glimepiride, you may have a blood glucose meter. These tablets may increase the chances of a low blood glucose or hypoglycaemia episode when the blood glucose falls below 4mmol/L
- Please check your blood glucose at 6am if your operation is in the morning, or before breakfast if your operation is in the afternoon. If you are driving, check your blood glucose before starting the car and drive only if your blood glucose is more than 5mmol/l
- Please inform staff at the hospital if you have needed to take any hypo treatment because it is possible that your surgery may have to be rearranged for another day.
For further information on how to treat hypoglycaemia or low blood glucose levels less than 4mmol/L please visit the Trend Diabetes website.
Things to bring with you to hospital
- Hypo treatments (glucose drink, tablets or jelly babies) if you are on tablets like Gliclazide, Glimepiride, Glibenclamide, Glimepiride
- Blood glucose testing equipment if you usually test
- Your usual medications.
During your operation
If you are likely to miss more than one meal, or if your blood glucose is high at the time of the operation, you may be given an intravenous insulin infusion (a combination of insulin and fluid given into a vein). This will be continued until you are ready to eat and drink.
After your operation
It is not uncommon to experience changes in blood glucose levels after your operation. Your blood glucose will be monitored after the operation and additional insulin given if necessary. The glucose targets may change for safety reasons.
After your operation you will be offered food and drink when you feel able to eat.
Once you are eating and drinking normally, you should restart your normal insulin from that meal onwards. Your blood glucose levels may be higher than usual for a day or so.
At home
Continue taking your usual medication as advised by your healthcare team.
If you normally have a blood glucose meter, monitor your blood glucose levels more often as this may be higher than usual for a day or so. This is not a problem unless you are feeling unwell.
If you feel unwell, especially if you are vomiting and unable to eat or take medication, please seek medical attention.
For more information on what to do when you are ill, please visit the Trend Diabetes website.
Contact your usual diabetes team/GP surgery or local out-of-hours service for advice. If you usually attend the hospital for diabetes care, please telephone the Diabetes team on 01305 255342.
What to do with your medications before surgery
| Name of medication | Day prior to surgery | Day of surgery if your operation is in the morning | Day of surgery if your operation is in the afternoon |
|---|---|---|---|
| Acarbose | Take as normal | Omit the morning dose | Take the usual morning dose with breakfast |
| Repaglinide Nateglinide | Take as normal | Omit the morning dose | Take the usual morning dose with breakfast |
| Metformin | Take as normal | If taken once or twice a day – take as normal If taken three times per day, omit the lunchtime dose | If taken once or twice a day – take as normal If taken three times per day, omit the lunchtime dose |
| Glibenclamide Gliclazide Glipizide Glimepiride | Take as normal | If taken once daily in the morning – omit the dose that day If taken twice daily – omit the morning dose that day | If taken once daily in the morning – omit the dose that day If taken twice daily – omit the morning dose that day |
| Pioglitazone | Take as normal | Take as normal | Take as normal |
| Sitagliptin Vildagliptin Saxagliptin Alogliptin Linagliptin | Take as normal | Take as normal | Take as normal |
| GLP1 injections Exenatide (Byetta®, Bydureon®) Liraglutide (Victoza®) Lixisenatide (Lyxumia®) Dulaglutide (Trulicity®) Semaglutide (Ozempic®) GLP1 tablet Semaglutide (Rybelsus®) | Take as normal | Take as normal | Take as normal |
| Canagliflozin Dapagliflozin Empagliflozin Ertugliflozin | Omit | Omit on the day of surgery | Omit on the day of surgery |
Contact numbers
We hope that you have found this information useful. If you have any questions or are worried about anything, please speak to the Pre-operative Assessment Unit on 01305 254222 or the diabetes nurse specialist on 01305 255342.
About this leaflet
Author(s): Amelia Denham, Deputy Sister, Pre-assessment Department, Dr Claire Joannides, Consultant Anaesthetist and Pre-assessment Lead and Dr Mo-Lee Wong, Consultant Diabetes and Endocrinology
Written: February 2023
Approved: October 2023
Review date: October 2026
Edition: v1
If you have feedback regarding the accuracy of the information contained in this leaflet, or if you would like a list of references used to develop this leaflet, please email patientinformation.leaflets@dchft.nhs.uk
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