Gastroscopy & Colonoscopy

HOW TO PREPARE FOR GASTROSCOPY & COLONOSCOPY

What is a Gastroscopy?

I think that there might be a problem with your food pipe, stomach or small bowel (oesophagus, stomach and duodenum) and therefore recommend that you have a procedure to examine these areas so that I can decide if you need any treatment.

During gastroscopy, I would pass a small tube with a camera through your mouth until your small bowel (duodenum). Rarely I might have to pass the scope through your nose. 

What is a Colonoscopy?

I think that there might be a problem with your colon or the last part of your small bowel (terminal ileum) and therefore recommend that you have a procedure to examine these areas so that I can decide if you need any treatment.

During Colonoscopy, I would pass a small tube with a camera from your anus until your small bowel (terminal ileum). I might also take samples from your colon called biopsies or remove polyps that might become cancer in the future. 

Where do I go on the day of the procedure?

You will go directly to the endoscopy unit.

How do I prepare for the procedure?

In order to achieve the best results, the preparation for colonoscopy for the purpose of polyp detection starts 5 days before the procedure and is divided into 4 steps. However we do not strictly follow this rule especially in emergency and semi-urgent endoscopy. 

• STEP 1 – 3 DAYS BEFORE PROCEDURE
  • You start taking Low Residue Diet – avoid vegetable, fruits and nuts

• STEP 2 – 1 DAY BEFORE PROCEDURE
  • Take clear liquids or semi liquids like clear apple or orange juice, jelly or clear chicken soup.

• STEP 3 – BOWEL PREPARATION
  • You will be given 3 sachets of Fortrans which is a medication that causes diarrhoea to clear your colon. 
  • Each sachet of Fortrans should be diluted in 1 liter of water and consumed within 1 hour. You can add some orange or lychee cordial for taste. 
  • The timing of your Bowel Preparation depends on the time of your Colonoscopy.

MORNING COLONOSCOPY
DAY BEFORE PROCEDURE		DAY OF PROCEDURE
6 pm	8 pm	5 am	8 am
1 sachet Fortrans in 1 litre of water	1 sachet Fortrans in 1 litre of water	1 sachet Fortrans in 1 litre of water	Colonoscopy

EVENING COLONOSCOPY
DAY OF PROCEDURE
6 am	8 am	10 am	2 pm
1 sachet Fortrans in 1 litre of water	1 sachet Fortrans in 1 litre of water	1 sachet Fortrans in 1 litre of water	Colonoscopy

• STEP 4 – FASTING
  • Your last drink must be 2 hours before the procedure in order to make sure your stomach is empty during endoscopy.

Why is it important that I fast before the procedure?

You must fast, that is not eat or drink 6 hours before the procedure in order to make sure your stomach is empty during endoscopy. An empty stomach is important to prevent the contents of your stomach from entering into your lungs while you are sedated and to ensure important findings such as cancer are not missed during endoscopy. 

Image from Coleski et al.¹ 

Why is it important that I prepare my bowels before the procedure?

You must prepare your bowels for 3 days for the best results during endoscopy. Many researches have proven that a clear colon increases detection of polyps that can become cancer. While Fair bowel preparation can cause small polyps to be missed, Inadequate bowel preparation can cause large polyps and cancer to be missed. In most instances the Colonoscopy will have to be repeated on another day with repeat bowel preparation unless you refuse. Additionally Good bowel preparation reduces the risk of tearing your colon and surgery to repair it. 

Image from Park et al.¹

As seen in the picture, a colon full of feces/stool cannot be examined completely. 

If I cannot drink or eat, can I take my medications?

You can take your medications with sips of water in the morning on the day of the procedure.

I am a Heart Patient, I am restricted to only 1 litre of liquid per day.

Fortrans in 1 litre of water will enter your mouth and come out through your anus as diarrhoea in order to clear your colon, it will not be absorbed into your body. This will not count towards your 1 litre of fluid restriction. Fortrans is the safest and the only bowel preparation approved for heart patients. 

I am a Kidney Patient on Dialysis, I am restricted to only 500ml of liquid per day.

Again, Fortrans in 1 litre of water will enter your mouth and come out through your anus as diarrhoea in order to clear your colon, it will not be absorbed into your body. This will not count towards your 500ml of fluid restriction and does not need to be extracted during dialysis. Fortrans is the safest and the only bowel preparation approved for kidney patients. 

I am a Heart Patient, should I stop my blood thinners?

Please remind me and the nurse that you are taking blood thinners. Please bring the name, photo or the medication with you. However, please continue taking your blood thinners such as Aspirin, Clopidogrel, Prasugrel, Apixaban, Dabigatran, Rivaroxaban and Warfarin. DO NOT STOP unless I instruct you. 

I am a Diabetic, what do I do with my tablets?

If you are on the newer drugs called SGLT-2 inhibitors such as Empaglifon (Jardiance), Dapaglifozin (Forxiga) and Canaglifozin (Invokana), you must stop it 3 days before the endoscopy.² These medications cannot be used when you’re fasting. 

All your other diabetes tablets should be taken AFTER endoscopy as you will be fasting overnight. 

I am a Diabetic, what do I do with my Insulin?

Please reduce the night dose of your insulin by 20%.² The morning dose of your insulin can be injected AFTER your endoscopy.

I have got High Blood Pressure, should I eat my medications?

Please take your Blood Pressure medications with sips of water BEFORE coming to the hospital.

If you are on GLP-1 (Wegovy, Saxenda, Ozempic, Mounjaro) for Obesity?

GLP-1 agonists should be withheld for 1 week before endoscopy and you should consume only clear liquids during the 24 hours before the procedure.³ This is to reduce the risks of your stomach contents entering your lungs during the procedure as these medications slow the movements of food in your stomach. 

What other medications should I stop?

If you are taking Omeprazole, Lansoprazole, Rabeprazole, Esomeprazole, Pantoprazole, Ranitidine, Cimetidine and Famotidine, then please stop these medications 2 weeks before endoscopy. You can take Gaviscon as required until the day of the procedure. 

You also need to stop antibiotics 1 month before endoscopy as both these types of medications affect Helicobacter Pylori (H.Pylori) testing. However this is not absolute especially in emergencies.

What about my Vitamins and Supplements, should I stop?

Yes. Please stop all vitamins and supplements 1 week before endoscopy as it interferes with the examination, especially iron tablets and iron containing supplements. 

What other information should you inform me?

It is very important to inform me or the nurse if you are pregnant, have a pacemaker or have an implantable cardiac defibrillator. While endoscopy is safe in pregnancy, it is generally postponed until the second trimester unless absolutely necessary.⁴ Patients with pacemakers and defibrillators will require consultation with a cardiologist. 

Drug Allergies.

It is very important to inform me or the nurse if you have any drug allergies especially to painkillers and antibiotics. We use medications such as Pethidine, Fentanyl and Midazolam for sedation and antibiotics such as Ceftriaxone during the procedure which commonly causes a mild rash, but rarely can cause an allergic reaction. 

Travelling for your Endoscopy.

Endoscopy procedures are almost always performed under conscious sedation which means we will give you medications such as painkillers and sedatives to make you drowsy and sleepy. You must not drive or make important decisions for the next 24 hours. 

Please ensure somebody drives you and accompanies you for your endoscopy appointment. Alternatively you can use public transport like Taxi or GrabCar.  

Valuables

Please DO NOT bring any valuables on the day of the procedure such as jewelleries. You will be asked to remove it as metal items can interfere with our equipment.

Consent Form

A consent form should be signed before the test after being given all the important information as this allows you the opportunity to ask questions. This may be signed by yourself or may require to be signed by someone on your behalf. You can withdraw your consent anytime before the procedure. 

How are the scopes cleaned?

After each use they are thoroughly cleaned, disinfected and sterilised. The hospital cleans and

disinfects all scopes according to the specifications set by the manufacturer and International Guidelines.

Single Use Disposable Endoscope.

However, if you are concerned about the sterility of the endoscope, then you can now opt for single use disposable endoscope, this however costs significantly more. Please inform us if you wish to have a single use endoscope and we will give you a quotation.  

In order to save you some money, we can use the same disposable endoscope for gastroscopy first then followed by colonoscopy as this is an acceptable practice and carries no additional risks to the patient. 

CONSENT

About the Condition

I would have explained the purpose for Colonoscopy such as acid reflux, stomach pains or checking for cancer. 

Investigation Options and Alternatives

Colonoscopy enables me to see the abnormality directly and take biopsies to determine the problem. 

Other options such as Barium Swallow and CT scan involve both radiation and contrast, but I will not be able to take biopsies. 

Treatment Options

Treatment options will depend on the nature of the problem.

Benefits

To diagnose and treat conditions involving the food passage (esophagus, stomach and duodenum).

Risks

Complications following esophagogastroduodenoscopy (EGD) are rare, occurring in less than 2% of patients. These could be related to sedation, endoscopy, and complications related to diagnostic or therapeutic maneuvers.⁵ 

Complications following colonoscopy are also rare, occurring in less than 1% of patients. These could be related to sedation, endoscopy, and complications related to diagnostic or therapeutic maneuvers.⁶ Additionally, there is a 9.4% risk that Endoscopy might miss abnormalities or cancers.⁷ 

Possible Adverse Effects or Complications

The most frequent and serious complications of sedation involve your heart and breathing. Adverse events from sedation include drop in oxygen level, slow breathing, low blood pressure, blocked breathing passage, irregular heartbeat and food particles going into lungs. Patients have rarely suffered heart attack or stroke, but these are usually very frail patients. We continuously monitor you throughout the procedure to reduce the risks.

The complications following Gastroscopy include infection, bleeding, injury or tear to your food pipe, stomach or small bowel. The risk of bleeding following Colonoscopy with biopsy is 0.3%. a tear to your food pipe, stomach or small bowel occurs in less than 0.3 % of cases but this might require surgery to repair, and infection is rarely reported. Complications typically are identified in the first 24 hours after the procedure. Another rare but important risk to note is a possibility of damage to your teeth. 

The complications following Colonoscopy include infection, bleeding, injury or tear to your colon or small bowel. The risk of bleeding following Colonoscopy with biopsy is 0.41%. a tear to your colon or small bowel occurs in less than 0.1% of cases but this might require surgery to repair, and infection is rarely reported. Rarely, in patients who had polyps removed, there is a 0.16% risk of developing stomach pains after polyp removal called post-polypectomy syndrome. Complications typically are identified in the first 24 hours after the procedure.⁶

Residual Effects

Sore throat lasting 2-3 days is the most common residual effect reported. Some minor blood spots are normal if polyps are removed. You might experience some pain or discomfort if your hemorrhoids were banded.  

Likely Results If Treatment Not Undertaken

Possibility to miss polyps,  ulcers or cancers. 

Minors⁸

It is important to note that for the purposes of the Regulations, a patient who is unmarried and below 18 years of age does not have the capacity to give valid consent to any medical procedure or surgery in Malaysia.

Patients Who Are Incapable of, or Impaired with, Decision-Making Ability.⁸

Some patients might not be able to give consent such as those with dementia. When there is a relative, next-of-kin or legal guardian available, and the relationship well established or confirmed, the consent may be obtained from such a person if an elective or non-emergency operation is necessary according to the doctor.

Additional Procedures

I might occasionally take biopsies, burn or clip an ulcer, or remove a polyp. tie or inject glue into a swollen blood vessel leading to additional costs depending on findings during endoscopy. 

You can choose to perform diagnosis at first endoscopy and perform any treatment at a separate session but this costs more. Please inform me or the nurse if you wish to do so. 

Change of Mind

It is perfectly ok to change your mind even after you have signed the consent form. You can always inform me or the nurse if you no longer wish to have the procedure. Alternatively you can discuss your concerns with me such as pain and medication side effects.

WHAT TO EXPECT ON DAY OF PROCEDURE

Registration

On arrival, please take a number at the Registration Counter where you will be registered by the Counter Staff. You will then proceed to the Endoscopy Unit Counter where a nurse will perform a Safety Screening using a Checklist. 

Screening

The nurse will measure your blood pressure, heart rate, temperature, oxygen level and blood sugars if you are a diabetic. The nurse will also ask a series of questions regarding your health. Please inform the nurse if you are on blood thinners or if you have any concerns. 

Change of Clothes

You will be asked to remove your shirt and change into a hospital gown. You may keep your pants but you will have to remove your belt. 

Preparation for Procedure

The test can be carried out with a local anaesthetic throat spray to numb the throat or a conscious sedation (to make you drowsy and relaxed). However patients often prefer to be sedated for a pain free procedure.

A nurse will put a tube in the back of your hand if you are going to have some sedation. 

Waiting

You will then be taken into the waiting area and asked to lie down on a bed. You will wait for your turn. Occasionally emergency cases might cut the cue depending on their urgency. 

WHAT TO EXPECT DURING PROCEDURE 

Chaperone

All female patients will have a female nurse chaperoning them at all times during the procedure.

Local Anesthesia

Once you enter the Endoscopy Room, a nurse will spray your throat with the local anaesthetic to numb the throat. It tastes both bitter and spicy. You hold it for 30 seconds in your mouth before swallowing it. 

Monitoring Equipments

You will be connected to the monitoring machine for continuous monitoring of blood pressure, heart rate and oxygen level throughout the procedure.If you are having sedation, oxygen will be given via a small tube in your nose.

Mouth Piece

You will have a mouthpiece put into your mouth; this protects your teeth and the camera. You will not be able to talk with the mouthpiece and your saliva will drool. Please don’t swallow your saliva.

Gastroscopy Procedure

I will pass the camera into your mouth and down your food pipe so that I can examine your food pipe, stomach and small bowel.

Small tissue samples (biopsies) of the lining of the food pipe, stomach or small bowel will be taken to check for the bacteria H.Pylori and additional samples taken if needed to help find out what is wrong.

The whole process takes 10-15 minutes. 

Exposure

Next your bum / backside / behind will be exposed fully to enable safe insertion of endoscope into the anus. This is especially important for female patients in order to minimize the risks of inserting the Colonscope into the vagina (female private parts). You are welcome to use a gauze or tissue paper to cover up if you wish to do so to protect your modesty. 

Colonoscopy Procedure

I will pass the camera into your anus all the way to the small bowel (terminal ileum) so that I can examine your colon and small bowel.

Small tissue samples (biopsies) of the lining of the colon or small bowel will be taken to check especially in patients with diarrhoea and additional samples taken if needed to help find out what is wrong.

The whole process takes 20-30 minutes.

WHAT TO EXPECT AFTER PROCEDURE

Recovery

When the test is finished you will go to the recovery area, the recovery nurse will take your blood pressure, temperature, heart rate and oxygen level a few times and look after you until you go home. 

It is important for you to stay in your bed until the nurse tells you to go home. The sedation might not have fully worn off and you can fall and hurt yourself. 

You will be given something to drink and something to eat, then you can go home

Discharge 

I will briefly explain your results and a nurse will provide a copy of the report. You will then settle the outstanding bill before returning home. 

Follow-up

You will normally be given a follow-up appointment to see me as you might not remember the explanation given at the Endoscopy Unit due to the effects of the sedative. 

Biopsy Results

If you had any biopsy taken during the procedure, the results of the biopsy will be explained during the follow-up appointment. 

After Sedation

If you have had sedation it is advisable not to drive, drink alcohol, sign any legal documents or go to work for 24 hours 

After Endoscopy

You may have a sore throat after the procedure and your tummy may feel bloated for a few hours or you might have some crampy abdominal pains but this should pass usually after you have passed some wind. 

The next day you should feel OK but if you still have a tummy ache, feel unwell with a sore throat or bleeding,  please contact the clinic.

REFERENCE

1. Fig. 1. Aronchick bowel preparation scale. ResearchGate. Accessed January 9, 2025. https://www.researchgate.net/figure/Aronchick-bowel-preparation-scale_fig1_318765331

2. Dogra P, Anastasopoulou C, Jialal I. Diabetic Perioperative Management. In: StatPearls. StatPearls Publishing; 2024. Accessed December 4, 2024. http://www.ncbi.nlm.nih.gov/books/NBK540965/

3. GLP-1 Agonists and Retained Gastric Contents at Endoscopy: An Update. Accessed December 4, 2024. https://www.jwatch.org/na57481/2024/05/14/glp-1-agonists-and-retained-gastric-contents-endoscopy

4. Savas N. Gastrointestinal endoscopy in pregnancy. World J Gastroenterol WJG. 2014;20(41):15241-15252. doi:10.3748/wjg.v20.i41.15241

5. Ahlawat R, Hoilat GJ, Ross AB. Esophagogastroduodenoscopy. In: StatPearls. StatPearls Publishing; 2024. Accessed December 4, 2024. http://www.ncbi.nlm.nih.gov/books/NBK532268/

6. (PDF) Colonoscopy-related complications in a nationwide immunochemical fecal occult blood test-based colorectal cancer screening program. Accessed January 9, 2025. https://www.researchgate.net/publication/328904320_Colonoscopy-related_complications_in_a_nationwide_immunochemical_fecal_occult_blood_test-based_colorectal_cancer_screening_program

7. Waddingham W, Kamran U, Kumar B, Trudgill NJ, Tsiamoulos ZP, Banks M. Complications of diagnostic upper Gastrointestinal endoscopy: common and rare – recognition, assessment and management. BMJ Open Gastroenterol. 2022;9(1):e000688. doi:10.1136/bmjgast-2021-0006888.

8. Consent_Guideline_21062016.pdf. Accessed December 4, 2024. https://mmc.gov.my/wp-content/uploads/2019/11/Consent_Guideline_21062016.pdf