Procedure and preparation for a colonoscopy

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A colonoscopy is not as scary as it seems; it's quick, low-pain, with a fast recovery.

Preparing for a colonoscopy (Colonoscopy Steps) is a very important procedure. In addition to seeing lesions clearly, it also helps your doctor make a preliminary diagnosis in a timely manner. However, patients who undergo a colonoscopy do need to prepare in advance in to get maximum benefit.

Preparation for a colonoscopy

  1. In the case of congenital disease that require regular medication, please inform your doctor. Certain medications may have to be stopped because they can affect the colonoscopy results. In particular, blood clot dissolving medicines such as Aspirin, Warfarin, Ticlid , Clopidrogrel, or NSAIDs (non-steroidal anti-inflammatory drugs), vitamin E, and fish oil, which must be discontinued at least 5 days before the examination.
  2. Eat soft, easily digestible foods, and abstain from fruits and vegetables 2 days in advance to prepare the intestines.
  3. Consult with a gastroenterologist via free video call before undergoing a colonoscopy to obtain any history of congenital disease, explain the treatment plan, indications, and possible complications. Please inform your doctor if you are allergic to any medicines, or have a chronic disease, such as heart disease.
  4. After consulting with a gastroenterologist, a specialist nurse will contact you to guide you on how to prepare for the procedure and make an appointment for the colonoscopy.
  5. Abstain from meat and dark fruit juices such as grape juice, concentrated chicken soup, and all dairy products. Consume only clear liquid food such as clear soups, juices, or jellies 1 day before the examination.
  6. Come to the hospital in the morning for bowel preparation under the supervision of a specialist nurse. A gastroenterologist will perform the colonoscopy in the afternoon. In the case where it is more convenient for the patient to take the medication at home, the hospital will deliver the medicine to your home free of charge.

Colonoscopy Procedure

Steps on the day of the colonoscopy

  • After arriving at BNH Hospital, please contact the Gastrointestinal and Liver Centre on the 3rd floor.

For those who undergo preparation at the hospital:

  1. Conduct a comprehensive health history assessment and undergo intestinal preparation under the supervision of a specialist nurse in the morning, in a private room.
  2. When the intestines are ready, a gastroenterologist will perform the colonoscopy.
  3. After the colonoscopy is completed, the patient will receive further care in the recovery room for 1 – 2 hours, or until waking up.
  4. Get the examination results from your doctor on the day of the colonoscopy.

For those preparing at home:

  1. Conduct a comprehensive health history assessment and perform another enema before entering the examination room for the best results of the colonoscopy.
  2. Start the colonoscopy examination process.
  3. After the colonoscopy is completed, the patient will receive further care in the recovery room for 1 – 2 hours, or until waking up.
  4. Get the examination results from your doctor on the day of the colonoscopy.

    * Colonoscopy time may be changed as appropriate. This depends on the time of the intestinal enema.

Colonoscopy Process

  1. 1. The patient lies on their left side, with knees bent close to the chest.
  2. The doctor gives the patient sleeping pills, and may also give painkillers, and then inserts an endoscope into the anus to examine the colon. This task takes approximately 25-30 minutes.
  3. If abnormalities or lesions are found in the large intestine, the doctor may take a biopsy for further pathological examination and remove the tumors that are not too large.
  4. After the colonoscopy is completed, the patient will receive further care in the recovery room for 1 – 2 hours, or until waking up.
  5. Observe unusual symptoms that may occur, such as abdominal pain, abdominal stiffness, severe abdominal discomfort, tenderness, high fever, or vomiting.
  6. Examine the stool, which may contain blood, and report to the doctor if there is any excessive bleeding.
  7. Get the examination results on the same day of the colonoscopy.


Post-Colonoscopy Instructions

  • In the case that the patient chooses to have a colonoscopy using sedation (general anaesthesia), please refrain from driving or working on the day of receiving the colonoscopy. Driving is not allowed. There must be a caregiver to take the patient home.
  • Follow the doctor’s instructions and seek medical attention according to the plan to monitor symptoms, especially in the case of biopsy.
  1. If you have any questions about whether standard medication will affect the examination, please consult your doctor before the examination.
  2. The patient must sign a consent form before the examination. If you are under the age of 20, your parents must sign the consent form on your behalf. The doctor will explain the benefits and complications of this procedure.

Why undergo a colonoscopy at BNH Hospital?

  • We have an experienced team of doctors and nurses specialized in the gastrointestinal tract to monitor you closely.
  • We are equipped with the most modern tools, including an endoscope with AI technology from Japan.
  • There is a private endoscopic preparation room, so you don’t have to worry, even if you come alone.
  • The specialist nursing team will prepare the laxatives for you according to the appropriate process and time. No more worrying about difficult or incomplete defecation, or painful excretion when travelling.
  • If abnormalities are detected, we can treat and cure them from end to end.
  • Comfortable. Completed within 1 day. Includes both intestinal preparation and Colonoscopy.


Q : How do I prepare for a gastroscopy and colonoscopy?

A : In order to prepare for gastroscopy, the patient must abstain from food and drink for 6 – 8 hours. As for preparation for a colonoscopy, the patient should abstain from food and drink for at least 8 hours and take laxatives before the examination. In the case where the patient is taking blood clot dissolving or anticoagulant medicine, it is recommended to refrain from taking those 5 – 7 days before the gastroscopy and colonoscopy, or to seek medical advice in advance.


Q : Do I need to be hospitalized for an Colonoscopy?

A : The gastroscopy is a procedure that does not take long to complete. The patient preparation procedure can be done from home so there is no need to stay overnight at the hospital.


Q : How long does a colonoscopy take?

A : Examining the colon takes approximately 25-30 minutes.

Q : What symptoms may occur after an endoscopy? Is it necessary to stay overnight at the hospital?

A : After the gastroscopy and colonoscopy, you may feel drowsy from the medication. If you have no symptoms, you will be allowed to go home, but it is not recommended that you drive.

Q : What happens if a polyp is found?

A : The doctor can remove the polyp immediately through a colonoscopy, and sends it to be examined for diagnosis.

Q : If a polyp is found and surgically removed, does it cure the cancer?

A : The data show that regular colonoscopies and polyp removal can reduce the incidence of colon cancer. A colonoscopy is considered an examination that greatly reduces the risk of colon cancer.

Colonoscopy Packages by BNH Hospital
"Let our Digestive Care Centre take care of your digestive tract."

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