Use this link to enable the ReciteMe accessibility toolkit

Accessibility tools

Enable ReciteMe accessibility tools
Home > Patients and Visitors > Patient Information Library > Guidance for people with diabetes having a gastroscopy

Guidance for people with diabetes having a gastroscopy

The aim of this patient information is to help people with type 1 Diabetes Mellitus or type 2 Diabetes Mellitus who are on tablets and/or insulin for their condition. If you have type 2 Diabetes Mellitus managed by diet alone, you do not need to read this patient information.

Guidance for people with diabetes having a gastroscopyTo view a PDF you may need to download Adobe Reader.

Please read this patient information as soon as possible and well in advance of your appointment.

If you are having a colonoscopy at the same time as your gastroscopy, please read the patient information ‘Guidance for people with diabetes when taking bowel preparation’.

Day before your procedure

  • If you are not on insulin – take your medications as normal
  • If you are on insulin – see instructions below

Day of procedure

  • Do not have anything to eat for at least 6 hours before the procedure and only have a light meal before this time. You may have small amounts of water up to 2 hours before your appointment time. You should have nothing to drink for at least 2 hours before the test.
  • If you are not on insulin – do not take your morning dose of tablets. If you have an afternoon appointment you will also need to omit (leave out) your lunchtime dose.
  • If you are on insulin – see information below. Check your blood glucose regularly.

What to do if you have a hypo whilst fasting

  • If blood glucose is below 4mmol/L, treat with 4 glucose tablets (suck, don’t chew) OR 4-5 teaspoons sugar dissolved in a small amount of water.
  • Test your blood glucose after 10-15 minutes and if it is still below4mmol/L repeat the treatment. Hypo treatment can be repeated up to 3 times if your blood glucose stays below 4mmol/L. If you have a hypo during the 2-hour time when you are not allowed to eat and drink, please treat with glucose tablets OR sugar as above.
  • Continue to monitor blood glucose levels hourly, until after the procedure.
  • Please make the endoscopy staff aware if you have had hypos whilst preparing for your procedure.

For patients taking insulin only

Biphasic mixed insulin/Twice daily

(Novomix 30, Humulin M3, Humalog Mix25, Humalog Mix50, Insuman Comb25, Insuman Comb50)

Day before procedure

  • Take your usual dose.

MORNING appointment – day of procedure

  • Do not take your morning dose.
  • If eating lunch, take half of your usual morning dose before lunch (bring your insulin and a sandwich with you).
  • Take your usual dose with your evening meal.

AFTERNOON appointment – day of procedure

  • Take half your usual morning dose.
  • Take your usual dose in the evening.

Day after procedure

  • Take usual dose of insulin.

Bolus (short‑acting) insulins

Actrapid, Apidra, Fiasp, Humalog, Humulin S, Insuman Rapid, Lyumjev, Novorapid

Day before procedure

  • Take your usual dose.

MORNING appointment – day of procedure

  • Do not take your morning dose.
  • Take usual dose at lunch if eating and drinking (bring your insulin and a sandwich with you).
  • Take usual dose with evening meal if eating and drinking.

AFTERNOON appointment – day of procedure

  • Take usual morning dose if eating breakfast.
  • Do not take lunchtime dose if not eating.
  • Take usual dose with evening meal if eating and drinking.

Day after procedure

  • Take usual dose of insulin.

Basal (long‑acting) insulins

Abasaglar, Humulin I, Insulatard, Insuman Basal, Lantus, Levemir, Semglee, Toujeo, Tresiba

If taken in the morning:

Day before procedure

  • Take your usual dose.

MORNING appointment – day of procedure

  • Reduce your usual dose by 20%.

AFTERNOON appointment – day of procedure

  • Reduce your usual insulin dose by one third.

Day after procedure

Take usual dose of insulin.

If taken in the evening:

Day before procedure

  • Reduce insulin dose by 20%.

Day of procedure for ALL appointments

  • Take usual dose of insulin.

Day after procedure

  • Take your usual dose of insulin.

Patients with Type 1 Diabetes MUST NOT OMIT basal insulin

Continuous Subcutaneous Insulin Infusion (CSII) & Hybrid Closed Loop (HCL) pump users

  • Users of CSII may need to use a temporary base rate reduction of 10% from 6am on the morning of the test to maintain a blood glucose of 5-10mmol/l.
  • HCL pump users’ basal level should be adjusted in line with glucose level.
  • Your insulin pump should remain in-situ throughout your procedure.
  • If unsure, please contact your specialist pump team for advice.

Useful contact numbers

For appointments and general enquiries (8.30am to 5.00pm Monday to Friday). Our booking service covers all sites so please ring any of the numbers below.

01205 445072

01476 464366

01522 573849

For procedure related enquiries (8.30am to 6.00pm Monday to Friday)

Boston           01205 446559

Grantham      01476 464085

Lincoln           01522 573016

Louth              01507 631236

For more information please see: www.ulh.nhs.uk/services/endoscopy