Bowel cleansing: in 3 steps


This is usually the most troublesome part of your procedure:

  • Step 1:  48 hours before: "the white diet" with low fibre and roughage (day -2)
  • Step 2:  24 hours before: clear fluids only (day -1)
  • Step 3:  Laxative drinks (don't follow the instructions on the Prepkit C or Prepkit Orange packet!)
    • For a procedure after 10am, take two sachets the afternoon or night before and, one in the morning 4 hours before the test. 
    • For a procedure before 10am, take the third sachet at 9pm.
    • Some occasionally will need an enema on test day.

See 10 tips for surviving the bowel prep below.

Please don't deviate from the instructions without discussing with the doctor. If bowel cleansing is inadequate, you may be cancelled or rescheduled, as abnormalities including bowel cancer may be missed.

48-24 hours before colonoscopy


Limit: seeds including bread with seeds, nuts, uncooked vegetables, skins and whole grains

Enjoy "the white diet": white rice/bread/pasta, rice bubbles or cornflakes, congee, fresh white fish, poultry (without skin),  bacon, pork or chicken sausage, eggs (one yolk only - eg, white scrabbled eggs with 1 yolk), boiled peeled potatoes or pumpkin, potato salad (without skin or greens), hash browns, canned or well cooked vegetables without skins or seeds. Milk and foods made from milk if tolerated eg. plain yoghurt, margarine, butter,  ice cream,  chocolate, cream/cottage/ricotta/fetta cheese. Macaroni cheese or pasta carbonara (no tomato or bottled sauces), plain bagels or white toast with vegemite/honey/lemon butter/butter, French or cinnamon toast, plain or ham/cheese croissant, honey and crumpets or pancakes, chocolate brioche, rice custard, chocolate mouse. cheese and crackers/rice cakes, protein bars without nuts or seeds, wedges with sour cream, ham quiche, parmesan cheese sticks, scones with honey, waffles or pikelets with lemon/sugar/honey.

Enjoy all clear fluids below. If you prefer raw fruits and vegetables, use a juicing machine to remove their pulp before consumption.

Avoid these white foods: pears, parsnip, cauliflower, onion, high fibre white breads (e.g. Wonder White), tofu, coconut, porridge, banana, mushrooms, semolina, couscous, popcorn

24 - 2 hours before colonoscopy


Water, clear fruit juices (apple, pear, white grape), coconut water, jelly, skim milk, Bonox, black tea/coffee, honey, carbonated beverages, clear cordials (lemon/lime), Ensure ® (<3 cans), sports drinks (eg.Gatorade ®), popsicles, sorbet/gelati. Clear broth/bouillon or Vietnamese pho broth (STRAIN chicken/ beef/vegetable noodle soups), thin congee, Hard/gelatine sweets (eg. barley sugars, lollipops, gummy bears), small volume of clear alcohol (light beer, white wine, vodka, gin, whiskey etc)

Take care to avoid dehydration.

Drink 2-3 glasses or serves of clear fluids throughout the day at: breakfast, morning tea, lunch, afternoon tea, dinner and evening (and test morning up to two hours prior)


No solid food, full cream milk nor red/purple food colouring

Buy Prepkit Orange or Prepkit C (3 sachets) well in advance from a local pharmacy

(No prescription required):


"PICOPREP" (x2 picosulfate): add (sachet A or C) to ONE 250mL glass of warm water (if preferred, chill in a refrigerator before drinking), drink over 30 minutes

"GLYCOPREP C" (x1 macrogol): add (sachet B) to FOUR 250mL glasses (or 1L jug) of warm water (if preferred, chill in a refrigerator before drinking).  Drink 1 glass every 15 mins. If you start to feel nauseous, slow down

take two sachets the evening before and one on test day

Expect diarrhoea (30 mins to 4 hours) after drinking laxative sachet




Your options for the third (Picoprep) sachet depend on when you like to sleep. They are to take it:

  • at 9pm  (ie take each at 5pm, 7pm, 9pm) - most common
  • at 3pm  (ie take each at 3pm, 5pm, 7pm)
  • 4 hours before (eg. for a 10am test, after setting your alarm! take each at 5pm, 7pm and the next day at 5-6am )


  1. Prepare laxative mixtures in advance and chill well
  2. If you feel nauseous, slow down
  3. Add lemon juice, ginger ale or lime cordial (but only if you never want to drink that beverage again in your life ! )
  4. Chill glass, drink with a straw and rinse mouth after drinking
  5. Suck on sweets
  6. Stock up on peppermint tea, lemonade iceblocks and ginger ale beforehand
  7. Apply Vaseline or Zinc oxide to your anal area in advance and use baby wipes instead of toilet paper
  8. Ensure safe, well-lit bathroom access, particularly at night, to prevent falls or accidents
  9. Don't be afraid to bring some entertainment to the bathroom, you'll be there a while
  10. Drink clear fluids right up to 2 hours before your test

If you feel you'd be more comfortable to be admitted the night before your colonoscopy for extra nursing care, please let our rooms know.

Sister Jenny Burns RN, our endoscopy practice nurse, will give you her number when she calls before and after your procedure. Sr Jenny is available to you if you would like to speak with her about your procedure or bowel preparation or you may like to call the hospital to speak with our endoscopy nurses.


These conditions may need special instructions for bowel preparation

consider "double prep" or extra prep:

  • diabetes
  • severe constipation consider 
  • prior inadequate bowel preparation

consider MoviPrep (avoid Picoprep):

  • severe kidney disease (eGFR<30)
  • liver cirrhosis (you take spironolactone)
  • heart failure (you take diuretics or EF<40%)

colonoscopy before 10am: see above