Issues for surgery
Increased risk of post-operative infection and delayed wound healing due to poor glycaemic control if omitted.
Potential for hypoglycaemia when taken concomitantly with other blood glucose lowering medicines and continued during nil by mouth period.
Combination product containing metformin – risk of lactic acidosis if continued (see Interactions with other common medicines used in the perioperative period and Further information).
Advice in the perioperative period
Elective and emergency surgery
Sitagliptin should be taken as normal the day prior to surgery.
EXCEPT:
- patients undertaking a liver reduction diet pre-operatively – see Patients undergoing surgery that requires liver reduction diet (LRD)
Consideration should be given to prescribing the components of combination products as separate medicines perioperatively.
Morning or afternoon surgery
Continue.
EXCEPT:
- as indicated above
- patient with eGFR < 60ml/min and having contrast media taking combination product containing metformin (Janumet®) – see also Metformin drug monograph
Consideration should be given to prescribing the components of combination products as separate medicines perioperatively.
Patients undergoing surgery that requires liver reduction diet (LRD) (e.g. bariatric surgery, gallbladder surgery)
For patients with type 2 diabetes mellitus commencing liver reduction diet (LRD), consideration should be given to stopping sitagliptin when the LRD commences, with close monitoring of capillary blood glucose (CBG) (see Further information).
For patients with type 2 diabetes mellitus not following a LRD, follow the advice above for elective and emergency surgery.
For information on combination product with metformin, also see Metformin drug monograph.
Perioperative Considerations
Commence variable rate intravenous insulin infusion (VRIII) perioperatively where indicated (see Further information) and withhold sitagliptin during VRIII treatment.
Ensure emergency treatment of hypoglycaemia is prescribed, i.e. Glucogel® and 20% dextrose. Rapid acting insulin should also be prescribed.
Post-operative advice
Restart once eating and drinking normally and VRIII (where applicable) has been stopped.
For combination product containing metformin – follow advice in Metformin drug monograph.
Patients undergoing bariatric surgery
Improved glycaemic control is expected because of reduced calorie intake, early satiety and weight loss following bariatric surgery, therefore discontinuation of sitagliptin should be considered post-operatively. Blood glucose should be monitored until eating habits and food intake stabilises. Patients should have their need for ongoing pharmacological management of their diabetes reviewed by their GP or bariatric surgical team.
Interactions with common anaesthetic agents
None.
Interactions with other common medicines used in the perioperative period
None for sitagliptin alone.
Iodinated contrast agents
Caution with combination product containing metformin and concomitant use of iodinated contrast agents – see Metformin drug monograph.
Non-steroidal anti-inflammatory drugs (NSAIDs)
Caution with combination product containing metformin and concomitant use of NSAIDs – see Metformin drug monograph.
Further information
VRIII
Patients with a planned short starvation period (no more than one missed meal in total) should be managed by modification of their usual diabetes medication, avoiding VRIII wherever possible (although VRIII may be necessary if emergency surgery or in people with poorly controlled diabetes (HbA1c >69mmol/mol)). Patients with type 2 diabetes who are expected to miss more than one meal should have VRIII if they develop hyperglycaemia (capillary blood glucose (CBG) >12mmol/L).
Liver reduction diet (LRD)
Obese patients often have a large, fatty liver which can cause difficulty for laparoscopic surgery, as the stomach cannot be easily accessed. The LRD typically starts 10 – 15 days prior to surgery and is based on low calories, in particular low carbohydrate and fat. This forces stored glycogen to be released from the liver (plus some water), making it softer, more flexible and easier to move. Due to the reduced calorie and carbohydrate intake, CBG levels will most likely be reduced. Whilst sitagliptin does not cause hypoglycaemia, the reduction in dietary intake means it is unlikely to have any benefit.
Lactic acidosis
Risk of lactic acidosis with combination product containing metformin – see Metformin drug monograph.
References
Busetto L, Dicker D, Azran C et al. Practical Recommendations of the Obesity Management Task Force of the European Association for the Study of Obesity for the Post-Bariatric Surgery Medical Management. Obesity Facts 2017;10:597 – 632. DOI: 10.1159/000481825
Centre for Perioperative Care. Guideline for Perioperative Care for People with Diabetes Mellitus Undergoing Elective and Emergency Surgery (March 2021). Available at: https://cpoc.org.uk/guidelines-resources/guidelines [Accessed on 8th March 2021]
Joint Formulary Committee. British National Formulary (online) London: BMJ Group and Pharmaceutical Press. http://www.medicinescomplete.com [Accessed on 27th February 2021]
Summary of Product Characteristics – Januvia® (sitagliptin) 100mg film-coated tablets. Merck Sharp & Dohme (UK) Limited. Accessed via www.medicines.org.uk 27/02/2021 [date of revision of the text May 2020]
Summary of Product Characteristics – Janumet® (sitagliptin + metformin) 50mg/1000mg film-coated tablets. Merck Sharp & Dohme (UK) Limited. Accessed via www.medicines.org.uk 27/02/2021 [date of revision of the text September 2020]