Before a colonoscopy, a person needs to drink a special fluid that clears their bowels to make any irregularities easier to spot during the procedure. Some people may refer to the fluid as a “colonoscopy prep drink”.

Tips such as splitting the dose and chilling the drink may make it easier to take.

A colonoscopy allows a doctor to see inside a person’s bowels and assess any irregularities. At the start of the procedure, a healthcare professional inserts a long, thin tube with a light and camera at the end into the person’s rectum.

Colonoscopy prep is essential. Without it, the doctor will be unable to see the bowels clearly and may need to repeat the procedure.

In this article, we discuss what colonoscopy prep drinks are and some strategies for drinking them. We also give a timeline of the overall preparation and describe what to expect on the day of the colonoscopy.

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Colonoscopy prep drinks vary, depending on an individual’s needs. Some come as powders that people mix in water. A doctor may recommend one of the following prep drinks:

The instructions for use vary, and a doctor or a member of their team will give specific directions. They may also recommend an additional oral laxative. A healthcare professional recommends a preparation plan that is tailored to each person’s situation.

People can usually combine their prep solution with a flavored sports drink to counteract the solution’s saltiness. However, check with a healthcare professional before adding anything to the prep solution.

Colonoscopy prep drinks often contain flavoring, but not everyone likes the taste, and drinking enough of the mixture can be a struggle. The following strategies might help:

  • Split up the prep: It is becoming more common for people to have half the mixture the night before their procedure and the remaining half the following morning.
  • Sip the drink: Doctors often advise people to drink the mixture gradually throughout the day. This can be especially helpful if the drink causes nausea.
  • Chill it: Some people report that the solution tastes worse when warm, so chilling it may help.
  • Use a straw: Drinking it with a straw can help the mixture bypass the taste buds.
  • Take a break: Anyone who experiences nausea or vomiting should take a 30-minute break before trying the drink again. If a person vomits, they should drink as much as possible and tell a healthcare professional.

People should check with their doctor’s staff about whether these strategies are suitable for their situation and the prescribed brand of prep solution.

Drinking the solution is just one part of the preparation plan. In addition, a person may need to take the following steps:

1 week before

If a person has diabetes or takes other medications, the doctor may alter their dosage. This applies to people who take drugs that influence blood clotting, such as warfarin or over-the-counter medications such as aspirin or ibuprofen (Advil).

3 days before

Medical staff typically recommend that 3 days before a colonoscopy, a person should avoid:

  • nuts
  • seeds
  • corn, including popcorn

Also, drink plenty of clear liquids and avoid anything with red, blue, or purple dyes. These colorings can make it seem as if there is blood in the colon.

Some examples of liquids that are OK to drink include:

  • pulp-free fruit juices, such as apple or white grape juice
  • coffee or tea without milk or creamer
  • clear broth or bouillon
  • carbonated soft drinks
  • Gatorade, Powerade, and similar light-colored drinks

2 days before

Start drinking at least 8 glasses of water or other liquids a day to prevent dehydration.

1 day before

The day before a colonoscopy, people should not have solid food. A person can have unlimited amounts of clear liquids and those in the list above.

Usually, a person starts drinking the prep solution at this time. Healthcare staff tend to recommend having half the night before and half on the morning of the colonoscopy.

The morning of the procedure

A person continues to have only clear liquids and no solid foods. By this point, they should be using the toilet regularly, and their stools should be clear.

Remember to stay hydrated. The preparation essentially involves giving a person diarrhea, so it is important to drink plenty of fluids until 2 hours before the procedure.

Stay near a toilet while drinking the prep solution and afterward. The need to use the bathroom may come on suddenly and frequently.

The aim is to eventually pass only clear or slightly yellow-tinted liquid as bowel movements. This shows that the bowel is clear and that the procedure is likely to produce accurate results.

On the day of the procedure, a doctor will explain the process and introduce the other healthcare professionals in the room.

The person will receive sedation medicine, and a healthcare professional will insert a thin, flexible tool called a colonoscope through their rectum. The scope sends images to a monitor, and the doctor uses this to examine the colon, looking for anything out of the ordinary. Using the same tool, they may remove polyps and take samples of tissue.

A person should not drive right after the procedure, as the anesthetic may still be in effect, so arrange for a ride home, if necessary. It can also be a good idea to take the rest of the day off to rest, if possible.

Drinking enough colonoscopy prep solution can be a challenge, but doing so helps ensure that the procedure is effective and leads to accurate findings.

The following strategies can help a person finish their prep drink:

  • having half the night before and half on the morning of the colonoscopy
  • chilling the drink
  • using a straw so that the drink bypasses the taste buds
  • having regular breaks between sipping the drink

People may find the colonoscopy preparation and the procedure unpleasant. However, it is worth noting that the colonoscopy may need repeating if a person does not take the prep correctly.