Preparing for your colonoscopy

Learn what you need to do to prepare for your colonoscopy:

  • Three days before your colonoscopy, eat only low-fiber foods.  Also, stop taking any fiber supplements or anti-diarrheal medication.
  • Two days before, continue eating only low-fiber foods.
  • One day before, go on a clear-liquid diet.
  • The evening before, drink half of a prescription laxative drink to clean out your colon for the procedure. (You'll finish it the next morning.)

Important: Arrange for someone to drive you home after the colonoscopy. Your test will have to be rescheduled if you don't have someone to accompany you home.

If you need to cancel your procedure, please cancel 5 business days (1 week) in advance.

Three days before your procedure

Start preparing three days before your colonoscopy. For example, if your colonoscopy is scheduled for Wednesday, you would start the low-fiber diet Sunday morning.

  • Stop taking any fiber supplements and anti-diarrheal medication
  • Eat only low-fiber foods, and avoid foods with certain dyes that may interfere with the test.

Low-fiber food chart

Confirm that a family member or friend is available to drive you home after your procedure and to stay with you for two hours afterward.

Two days before procedure

Continue eating only low-fiber foods. Avoid foods with certain dyes that may interfere with the test.

Low-fiber food chart

One day before procedure

  • Drink only clear liquids or certain light-colored beverages. (See the clear liquid chart below.)
  • Do not eat solid foods.
  • You will drink half of the laxative drink today, starting in the late afternoon.
  • Mix your laxative drink and start drinking it, following the instructions below or a handout from the medical center.  (Do not follow the instructions on the bottle itself.) Start drinking the laxative between 4 p.m. and 7 p.m. (You will need up to 6 hours to complete the laxative drink and finish bowel movements.)
  • Do not use alcohol, marijuana, or other substances that could impair your thought process.

Drink at least 8 glasses of liquid the day before your colonoscopy (in addition  to the laxative drink)  to prevent dehydration. See examples of what liquids you may drink and what to avoid:

Clear liquid chart

Mixing the laxative drink

The laxative drink is a prescription and you may pick it up at the pharmacy. Follow the instructions below or what you receive from our clinic. Don't follow the instructions on the bottle.

  • Fill the laxative container to half full. Shake well, and then finish filling to the top line.
  • Use flavoring packets (included with the laxative bottle) if needed. Try a little flavoring in a glass before mixing the packets with the entire bottle.

Drinking the laxative

  • Drink 8 ounces every 10 to 15 minutes. Try to drink quickly rather than sipping.
  • Drink half the laxative the evening before the procedure. This takes about 2 hours, drinking a glass every 10 to 15 minutes. Store the rest in the refrigerator until the morning of your procedure.

Day of the colonoscopy

If your procedure is in the morning, you may need to get up earlier than usual to finish drinking the laxative.

  • Drink the rest of the laxative 4 to 5 hours before you leave home for the procedure.  Our clinic instructions will have a specific time listed for you to start drinking based on your procedure time. It is ok to start drinking up to 1 hour earlier if you think you need to. Drink about an 8 ounce glass every 10 to 15 minutes, the same as the previous evening.
  • You must finish drinking any other beverage at least 2 hours before your appointment time.  This means that you need to calculate what time you need to get up so you have time to finish the prep drink 4 to 5 hours before leaving home.

The other liquids you may drink are the same as you had the day before your procedure. See the clear liquid chart.

Remember, you can't drink anything for at least 2 hours before your procedure.

You must have someone to take you home after your colonoscopy and stay with you for at least two hours.

Do not use alcohol, marijuana, or other substances that could impair your thought process prior to your appointment.

Do not drink alcohol, drive a car, or sign legal documents until the day after your procedure.

After your procedure

You will receive discharge instructions from your nurse after the procedure, including an after-visit summary with the results.

If tissue was removed, you will get a letter or phone call after your procedure with those results.

There is a very small risk of bleeding after a colonoscopy for up to two weeks. You should be within a two-hour drive of a medical center for two  weeks following your colonoscopy and avoid traveling outside of the United States during this time period.