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Diet guidance

Diet guide for colonoscopy prep

Easy-to-read guides for each phase of your preparation diet. Choose the section that matches where you are in your prep.

Print the food lists on this page, save this page as a PDF, download every phase in one combined document, or grab the one-page day-by-day plan and urgent help card to keep on the fridge.

Larger margins, black-and-white text and no coloured panels — easier and cheaper to print at home.

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We will send a secure download link for the sections you are viewing, including your saved procedure date and gluten-challenge advice if applicable.

When to follow this phase

Typically the day before your colonoscopy

A clear-liquid diet gives your digestive system a rest while keeping you hydrated and providing some energy. You can see through clear liquids, and they leave no residue in the colon.

Gluten challenge for Coeliac testing

Your doctor is taking biopsies to check for Coeliac disease. For the test to be accurate, you need to keep eating gluten before the procedure.

  • Continue eating normal amounts of wheat, barley, rye, and oats (if you usually eat them).
  • If you are already on a gluten-free diet, speak with your doctor about a formal gluten challenge before the test. A common challenge is the equivalent of 2 slices of wheat bread daily for about 6 weeks.
  • Do not start a gluten-free diet until after your procedure and your doctor has discussed the results with you.
  • The low-fibre and clear-liquid diet instructions still apply, but choose gluten-containing refined options where possible (e.g., white bread, plain wheat biscuits, white pasta) until your prep phase begins.

If you have already cut out gluten, let the clinic know before your appointment. Your doctor may need to reschedule the biopsies or adjust the advice.

Clear liquids you can have

These are typically allowed on a clear-liquid diet. Avoid anything with red, purple, or blue dyes unless your doctor says otherwise.

Hydration

  • Water and sparkling water
  • Clear broths and bouillon
  • Clear fruit juices without pulp
  • Clear sodas and sports drinks

Warm drinks

  • Plain black coffee without milk
  • Plain tea without milk
  • Clear fruit-flavoured drinks without pulp

Light snacks

  • Plain jelly without fruit
  • Ice blocks without fruit or cream
  • Clear boiled lollies

Sweets

  • Honey, sugar, and clear syrup
  • Plain sugar-based drinks

What to avoid

Do not drink or eat anything that is not clear or that leaves residue in the colon.

  • Milk, cream, and non-dairy creamers
  • Orange juice, tomato juice, or any juice with pulp
  • Smoothies, protein shakes, and meal-replacement drinks
  • Soups with noodles, vegetables, or meat pieces
  • Anything red, purple, or blue dyed
  • Alcohol
  • Solid food of any kind

Sample clear-liquid day

Morning

Black coffee or tea, water, clear juice

Midday

Clear broth, jelly, clear sports drink

Afternoon

Water, ice blocks, clear soft drink

Evening

Clear broth, jelly, water until cutoff

What to buy from your pharmacy

0 of 2 purchased

You do not need a prescription for any of these. Tick each item once you have it.

Morning admission (before 12:00 PM)

If your admission time is before 12:00 PM, follow this timetable the day before your procedure.

  1. From 8.00amA light breakfast from the white diet list BEFORE 8.00am (e.g. egg on white toast, cornflakes or Rice Bubbles, plain croissant or crumpets), then clear fluids only — no solid foods. Clear fluids include water, fizzy drinks, clear strained soup, clear stock, jelly, cordial (yellow and orange colours only), and black tea and coffee.
  2. During the dayMake up Dose 1 of Plenvu and store it in the refrigerator.
  3. 7:00 PMDrink your first dose of Plenvu slowly over 60 minutes, then an additional 500ml of clear fluid. Frequent watery bowel motions will occur — keep drinking clear fluids to prevent dehydration.
  4. Before bedMake up Dose 2 of Plenvu, cover it and store it in the refrigerator.
  5. 4:00 AM (procedure day)Or 4 hours before your admission time — drink Dose 2 of Plenvu plus an additional 500ml of clear fluid SLOWLY over 60 minutes. Peppermint tea beforehand can help; alternate 1 sip of Plenvu with 1 sip of clear fluid, and a straw can help.
  6. After your prepTake your regular medications with a sip of water 60 minutes after completing your preparation, then water only until 2 hours before your procedure — NIL BY MOUTH from 2 hours before.

Afternoon admission (12:00 PM or later)

If your admission is at 12:00 PM or later, use this timetable the day before your procedure instead of the morning list above.

  1. From 10.00amA light breakfast from the white diet list BEFORE 10.00am (e.g. egg on white toast), then clear fluids only — no solid foods. Clear fluids include water, fizzy drinks, clear strained soup, clear stock, jelly, cordial (except red or green), and black tea and coffee. Aim for about 2 litres (8–10 glasses) through the day, not counting the bowel preparation.
  2. That eveningBoth Plenvu doses are taken tomorrow morning — there is no prep to drink this evening.
  3. 5:30 AM (procedure day)Take your regular medications with a sip of water.
  4. 6:00 AMOver 30 minutes, drink Plenvu Dose 1 mixed in 500ml of water, then an additional 500ml of clear liquid. Frequent bowel motions will occur — keep drinking water or clear fluids to prevent dehydration.
  5. 8:00 AMOver 30 minutes, drink Plenvu Dose 2 (sachets A & B) mixed in 500ml of water, then an additional 500ml of water or clear liquid. Finish ALL Plenvu solution BEFORE 10.00am.
  6. From 10.00amWater only until 2 hours before your procedure — NIL BY MOUTH from 2 hours before.

Hydration tip

Drink plenty of clear fluids throughout the day to stay hydrated. Dehydration can make the prep solution harder to tolerate. If you feel nauseated, take small sips more frequently.