Fasting Guidelines

What you can eat and drink before your procedure

Standard Fasting Times

6 hours

No food

No solid food, milk, or drinks containing milk

2 hours

Clear fluids OK

Water, black tea/coffee, apple juice, clear cordial

Chewing gum & lollies = food — stop 6 hours before

YES:

NO:

Request a morning list to minimise fasting
Tablets (not SGLT2i): Skip morning dose. Restart evening meal.
SGLT2i (Forxiga, Jardiance): Stop 3 days before
GLP-1 (Ozempic, Wegovy, Mounjaro): If told to stop — 1 week (weekly) / day before (daily). If continuing — 24-hour clear fluid diet (ANZCA 2025)
Metformin + major surgery: Stop on day of surgery
Insulin: Adjust doses — see full diabetes guide

BGL Monitoring While Fasting:

Oral medications: Omit while on clear fluids. Restart at lunchtime after test.
Insulin: Requirements will be less (fewer carbs from clear fluids)
Check BGL 4–6 times daily during bowel prep
Type 1: Do not omit insulin — risk of DKA
Below 5.0 — glucose-containing clear fluids
Above 10.0 — water or clear diet drinks only
Unstable diabetes or large insulin doses — arrange admission during bowel prep

Do not drive to hospital while fasting
Take regular non-diabetes medications with a sip of water (unless told otherwise)
If surgery is delayed, tell staff you are diabetic
Bring insulin, injecting equipment, and hypo treatment