Colonic Lavage (Fortrans®)

What is this medication for?

This medication is also known as Macrogol or Polyethylene Glycol (PEG).

Colonic Lavage (Fortrans®) is a laxative used to clean out your bowel (large intestine) before:

• A camera examination of your bowel (colonoscopy or endoscopy), or
• Bowel surgery.

It works by drawing water into the bowel, which helps to flush out the contents of the bowel so that your doctor can clearly see the lining of the bowel during the procedure.

How should I take or use this medication?

• Each sachet must be dissolved in one litre (four glasses) of water. Stir well until the powder is fully dissolved before drinking.
• Your doctor will advise you on how many sachets to take and when to take them, based on your body weight and the time of your procedure. Follow the instructions given by your doctor or healthcare team closely.
• Drink the solution at a steady pace to complete the entire solution within the timeframe advised by your healthcare professional.
• Drink this solution while sitting upright. This helps to reduce the risk of the liquid accidentally entering your airway. If you have difficulty swallowing or tend to choke easily, please inform your doctor or nurse before taking this medication.
• The solution may be prescribed as a single dose the evening before your procedure, or as divided doses — part the evening before and part on the morning of your procedure. Your doctor or healthcare team will advise you on the schedule that is right for you.
• The solution should be finished at least three to four hours before your procedure.
• After finishing the solution, drink additional water to replace the fluids lost to prevent dehydration.

Please note: Your bowel preparation is successful when your stools pass out as a clear or light yellow liquid with no solid bits. If your stools are still dark or contain solid matter after finishing the solution, please inform your healthcare team as your procedure may need to be rescheduled. 

What should I do if I forget to take or use this medication?

If you forget to take a dose or are unable to finish the full amount of solution, do not take extra doses on your own to make up for it. Please inform your doctor or healthcare team as soon as possible, as your procedure may need to be postponed.

What precautions should I take when taking or using this medication?

Inform your healthcare professional if:

• You are allergic to this medication or any of the other ingredients of this medication.
• You are pregnant, planning to become pregnant, or breastfeeding.
• You are taking any other medications, including supplements, traditional medications and herbal remedies.
• You have kidney problems, heart problems, or are on a low-salt diet.
• You have a history of bowel problems such as inflammation of the bowels (e.g. Crohn's disease or ulcerative colitis), bowel blockage, or slow stomach emptying.
• You are taking blood-thinning medications (e.g. clopidogrel, rivaroxaban, aspirin) or diabetes medication (e.g. empagliflozin, dapagliflozin, semaglutide, liraglutide, dulaglutide, tirzepatide) as these may need to be stopped before your procedure. Follow your doctor's advice on when to stop these medications.

If you have any questions about this medication, please discuss with your healthcare professional.

What are some common side effects of this medication? ​

• Diarrhoea (loose and frequent stools) is an expected effect of this medication, as it is meant to clean out your bowel.
• Nausea and vomiting may occur at the start of taking the solution. These usually get better as you continue drinking.
• You may also experience stomach pain or bloating (a feeling of fullness or swelling in the stomach).

These side effects are temporary and should go away after you finish the solution and your bowel has been cleared.

What are some rare but serious side-effects that I need to seek medical advice immediately? 

The symptoms of a drug allergy include one or more of the following:

• Swollen face/eyes/lips/tongue
• Difficulty in breathing
• Itchy skin rashes over your whole body

If you experience any of these symptoms, you should stop your medication and see your healthcare professional immediately.

You can also find out about drug allergies by watching these videos:

For videos in 中文, Melayu and தமிழ், click here.

Other rare but serious side effects include:

• Severe stomach pain or rectal bleeding — this may be a sign of a serious bowel condition called ischaemic colitis (reduced blood flow to the bowel). Seek medical attention immediately if you experience this.
• Signs of low sodium or potassium levels in the blood, such as muscle cramps, numbness or tingling of the hands and feet, unusual tiredness, or an irregular heartbeat. Seek medical attention if you experience these symptoms.

What food or medication should I avoid when I take or use this medication?

• Take all your other oral medications at least two hours before starting the colonic lavage solution, as this medication may affect how other medications are absorbed by your body.
• If you are on blood-thinning medications, diabetes medication, follow your doctor's advice on when to stop these before your procedure.

On the day before your procedure (unless otherwise advised by your healthcare professional):

• Eat only light, low-fibre foods such as white bread, white porridge or rice, lean meat (chicken or fish), and eggs.
• Avoid dairy products (milk, yoghurt, cheese, butter), fruits, vegetables, and whole grains.
• Stop eating solid food as instructed by your healthcare team before you begin taking the solution.

How should I store this medication?

Store in a cool and dry place, away from direct sunlight. Do not store above 30°C. Keep this medication away from children

How do I throw away this medication safely? ​

Pack this medication into a black trash bag and seal it tightly before throwing into the rubbish chute or bin.