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CT Colon Full Dose Prep (Picolax/Omnipaque) Bowel Prep and Diet Sheet

Patient Information Leaflet

Two days before your scan:

You can eat low fibre foods including the following:

  • Milk (2 cups/day), plain yoghurt, cheese, butter, margarine
  • White fish or chicken: boiled/steamed/grilled
  • Eggs, Tofu, white pasta, white rice
  • White bread, white pitta, white flour chapattis
  • Potatoes with no skin, e.g. mashed or boiled
  • Clear soups with no solid bits, e.g. sieved chicken noodle, Bovril, Oxo
  • Clear jelly, boiled sweets, ice cream, chocolate (no fruit or nut pieces)
  • Salt, pepper, sugar, sweeteners, and honey

Have plenty to drink:

  • Tea, coffee, squash, fizzy drinks, water, clear fruit juices (e.g. apple, grape, cranberry)

Suggested meals could include for example:

  • Breakfast: White bread/toast with butter and honey Boiled or poached egg
  • Lunch/ Dinner: Grilled fish or chicken with white rice and boiled potatoes (no skin) Scrambled eggs on white toast, vanilla ice cream

Do not eat high fibre foods such as:

  • Fruit, vegetables, salad, mushrooms, sweetcorn, cereals, nuts, seeds, pips, bran, beans, lentils, brown bread, brown or wild rice, brown pasta, pickles or chutneys.
  • Do not eat red meats or pink fish like salmon/mackerel)

The day before your scan:

  • Have a light breakfast, choosing from the list of allowed foods (see above).
  • After this, do not eat any solid food until after your scan.
  • You can still have clear soups (e.g. sieved chicken noodle soup, vegetable Bouillon), jelly, ice cream, Ambrosia custard, Complan.
  • Drink plenty of fluids (tea, coffee, fizzy drinks, squashes, water, clear fruit juices, Bovril, Oxo) throughout the day.
  • Drink at least ¼ pint (150ml) of fluid each hour during the daytime.

If you are diabetic: Please monitor your blood sugar carefully and seek medical advice if you start to feel unwell.

At 8.00am:

Picolax image

  • Dissolve one sachet of Picolax in a cup of water and stir for 2-3 minutes. (see above)
  • The mixture will get warm - let it cool down, then add more cold water and drink it all.

At 2.00pm:

  • Dissolve the second sachet of Picolax in the same way and drink it all.

  • You can take all your usual prescribed medications but try to take it at least two hours before drinking the Picolax solution and at least six hours after, or they may not take effect.

  • Picolax is a laxative causing loose bowel motions taking effect within 2-3 hours, but this varies.

  • There is often more effect after the second dose.

  • You should expect frequent bowel actions and eventually diarrhoea.

  • Some intestinal cramping is normal.

  • Use a barrier cream (i.e. Vaseline) locally after each bowel action to help reduce soreness around the anus.

  • Please make sure you are near a toilet once commencing your bowel prep and remember to drink plenty of fluids.

The night before your scan:

Omnipaque bottle image

  • Before going to bed, mix the 50ml bottle of Omnipaque 240 in half a cup of water and drink it all.
  • This drink will enhance the fluid in your large bowel overnight making the CT scan images much clearer.
  • Before taking the Omnipaque, please inform the CT Radiographers on 02072883951 if you have an allergy to iodine or have had an allergic reaction to CT contrast in the past.
Published:
23 Feb 2024
Review:
23 Feb 2026
Reference:
ACW/Imag/D&BPPOCTVC/01