Bowel preparation for colonoscopy

How to take Halfprep (2 L liquid)

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Exam: (date) :

This is Gwanak Soo Internal Medicine Clinic. For patients having a colonoscopy, here is how to take the bowel preparation medicine Halfprep.

Taking it as instructed cleans the bowel so the exam goes well. If the bowel is not fully emptied, polyps are hard to find and you may need to have the exam again.

Your timeline

  1. From 3 days before Avoid the foods below
  2. Day before Light breakfast and lunch only · no food after 2 pm · water or sports drinks 0.5–1 L
  3. Date and time on your sheet 1st dose
  4. Date and time on your sheet 2nd dose
  5. 2 hours before the exam Stop drinking water
  6. Exam day Colonoscopy — no food on the day of the exam

Halfprep is taken in two doses. Please follow the dates and times checked and written on the instruction sheet the clinic gives you.

Food from 3 days before

Avoid

  • Watermelon
  • Korean melon
  • Strawberries
  • Grapes
  • Kiwi
  • Tangerines
  • Multigrain and brown rice
  • Sesame and sesame porridge
  • Corn
  • Nuts
  • Beans and bean sprouts
  • Kimchi and kkakdugi
  • Namul and spinach
  • Cabbage and salad
  • Green onions
  • Mushrooms
  • Chili pepper seeds
  • Gim (dried laver)
  • Miyeok and kelp

OK to eat

  • White rice
  • Plain rice porridge
  • Eggs
  • Tofu
  • Muk (jelly)
  • Fish
  • Lean chicken meat
  • Clear broth without solids
  • White bread
  • Castella (sponge cake)
  • Apples (no skin or seeds)
  • Pears (no skin or seeds)
  • Bananas
  • Potatoes
  • Water
  • Sports drinks
  • Clear juice

Foods to avoid from 3 days before the exam: fruits with seeds such as watermelon, Korean melon, strawberries, grapes, kiwi and tangerines; multigrain rice and brown rice; sesame and sesame porridge; corn; and nuts.

Also avoid beans and bean sprouts, kimchi and kkakdugi (radish kimchi), namul (seasoned vegetables) and spinach, cabbage and salad, green onions, mushrooms, chili pepper seeds, gim (dried laver), miyeok (seaweed) and kelp.

Foods you may eat: white rice and plain rice porridge, eggs, tofu, muk (jelly), fish, lean chicken meat, clear broth without solids, white bread and castella (sponge cake).

You may also eat apples and pears with the skin and seeds removed, bananas, potatoes, and drink water, sports drinks or clear juice.

On the day before the exam, eat only a light breakfast and lunch of plain rice porridge with soy sauce, broth without solids, or castella. Do not eat after 2 pm; after that, drink plenty of water or sports drinks, about 0.5–1 L. Do not eat on the day of the exam.

How to take it

You need one box of Halfprep and bottled water. The box contains 4 sachets of powder A, 4 sachets of powder B and a 500 mL mixing bottle.

  1. 1

    Mix

    How to mix: put 1 sachet of powder A and 1 sachet of powder B into the mixing bottle, pour cold water up to the 500 mL line, and shake well to dissolve.

  2. 2

    1st dose

    1st dose: drink 2 bottles (500 mL each) of the mixed medicine over 1 hour, 30 minutes per bottle. Then drink another 500 mL of water.

    ☐ Day before  ☐ Exam day  ·  ☐ AM  ☐ PM  ·   :

  3. 3

    2nd dose

    The 2nd dose is the same as the 1st: drink 2 bottles of medicine over 1 hour, then another 500 mL of water. Even if it is hard to drink, you must finish all of it for the exam to be possible.

    ☐ Day before  ☐ Exam day  ·  ☐ AM  ☐ PM  ·   :

Water

You drink a lot of water to prevent dehydration.

Drink water only until 2 hours before the exam; after that, do not drink even water.

Are you ready?

Stool colour changes from dark brown to brown, dark orange, light orange and finally clear yellow
  1. Dark brown
  2. Brown
  3. Dark orange
  4. Light orangeAlmost ready
  5. Clear yellowReady

When your stool comes out like clear yellow water, you are ready. Even if your stool is already clear, finish all of the medicine.

If this happens

While taking it, walking around or rubbing your belly empties the bowel better than lying down.

If you vomit a lot or feel very dizzy, stop taking it and call the clinic.

If you have heart or kidney disease, please talk to us before the exam.

Your usual medicines

Take blood pressure or heart medicine early in the morning on the day of the exam with a sip of water. Diabetes medicine and insulin are adjusted differently depending on the type and the exam time. Tell us the name and dose of your medicines when you book, and do as instructed. Do not stop all of them on your own.

If you take a blood thinner such as aspirin, clopidogrel or warfarin, be sure to talk to the doctor who prescribed it before the exam.

Gwanak Soo Internal Medicine ClinicIf you have any questions, call Gwanak Soo Internal Medicine Clinic at +82-2-871-1936.2F, 1810 Nambusunhwan-ro, Gwanak-gu, Seoul · Seoul Nat’l Univ. Station Exit 4
Scan to open this guide on your phonewww.gwsooclinic.com/en/prep/haprep

Video (Korean): watch on our Korean page · Other bowel preparations: Orafang (tablets) · OnePrep 1.38 (1.38 L liquid) · Back to the clinic page