Fortrans powder for oral solution – macrogol bowel cleansing before colonoscopy and surgery

Fortrans is a powder for preparing an oral solution used to completely empty the contents of the large bowel (colonic lavage) before bowel surgery and before diagnostic examinations such as endoscopy (colonoscopy) and radiological examination. It belongs to the osmotic laxative group and contains macrogol 4000 (high-molecular-weight polyethylene glycol) with added salts: sodium sulfate, sodium hydrogen carbonate, sodium chloride and potassium chloride.

The solution works by retaining water in the bowel, making the bowel contents more liquid and increasing the frequency of bowel movements. The medicine is intended for adults only, is available on prescription, and the way and timing of drinking the solution are adapted to the scheduled examination or procedure.

How is Fortrans used for bowel preparation before colonoscopy and other examinations?

Key facts about the medicine

What is Fortrans used for?

According to the package leaflet, Fortrans is used to empty the contents of the large bowel (colonic lavage) when:

• preparing patients for bowel surgery;
• preparing patients for diagnostic procedures involving rectal examination – radiological examination and endoscopy.

Fortrans is not a medicine for occasional constipation – it is used once, for bowel preparation, as recommended by the doctor.

How is the Fortrans solution prepared and taken?

• Dose: one litre of solution per 15 to 20 kg body weight, on average 3 to 4 litres of solution.
• Preparation: dissolve the contents of one sachet in 1 litre of water and stir until completely dissolved. Once prepared, the solution must be drunk without delay.
• Two split doses: 2 litres the evening before the procedure and 1 to 2 litres the next morning, or 3 litres in the evening and 1 litre the next morning – the last glass should be drunk 3–4 hours before the procedure.
• Single dose: 3 to 4 litres the evening before the procedure; a one-hour break may be taken after the first 2 litres.
• Drinking rate: 1 to 1.5 litres per hour is recommended (e.g. 250 mL every 10–15 minutes). The doctor may adjust the rate to your clinical condition.
• Food and drink: do not take food or drink while using the medicine, so that it can work fully and the bowel is adequately prepared.

After drinking the solution you will empty your bowels frequently – this is expected and shows that the medicine is working. Stay close to a toilet until the effect wears off.

Special patient groups

Children and adolescents: Fortrans must not be used in people under 18 years – safety and efficacy have not been established. Elderly patients: in elderly people in poor general health the medicine is given only under medical supervision.

Impaired kidney function: there are insufficient data; in kidney disease and heart failure there is a risk of fluid overload and acute pulmonary oedema, so monitoring is needed. Bedridden patients and people with swallowing difficulties: because of the risk of aspiration the medicine is given carefully and only under medical supervision, in a sitting position.

Contraindications – when the medicine must not be used

Do not take Fortrans:

• if you are allergic to macrogol 4000, anhydrous sodium sulfate, sodium hydrogen carbonate, sodium chloride, potassium chloride or saccharin sodium;
• if your general condition is severely impaired, such as dehydration, or you have severe heart failure;
• in advanced colon cancer or another severe bowel disease with a fragile mucosa;
• in severe acute inflammation of the digestive tract, including Crohn’s disease and haemorrhagic rectocolitis;
• in known bowel obstruction or a tendency to obstruction, stenosis, ileus or bowel perforation;
• in gastric emptying disorders (gastroparesis, gastric stasis);
• in toxic colitis or toxic megacolon;
• in children and adolescents under 18 years.

Warnings and precautions

• Tell your doctor before use if you have heart problems, kidney problems, difficulty swallowing or a tendency to aspiration, if you are bedridden or take diuretics.
• If there is a risk of electrolyte disturbance, the doctor may check blood electrolytes before and after use; existing disturbances should be corrected before lavage.
• Allergic reactions to macrogol have been reported – hives, rash and severe reactions with sudden swelling of the face, lips and tongue, shortness of breath and wheezing.
• Cases of ischaemic colitis have been reported with macrogol bowel preparation; caution is needed with known risk factors and with concomitant stimulant laxatives (bisacodyl, sodium picosulfate).
• One sachet contains 2.890 g of sodium – special caution on a sodium-controlled diet.
• The diarrhoea caused by the medicine can significantly disturb the absorption of other medicines taken at the same time.

Interactions with other medicines, food and drink

Medicines taken by mouth may be flushed out of the bowel before they are absorbed. They should therefore be taken more than 2 hours before drinking the solution, and other medicines should be avoided during and after the laxative until the examination is over. The efficacy of medicines with a narrow therapeutic range and short half-life, such as digoxin, antiepileptics, coumarin anticoagulants and immunosuppressants, may be particularly affected – agree the timing of these medicines with your doctor.

Do not take food or drink (other than the solution) while using the medicine, so that bowel preparation is complete.

Pregnancy and breast-feeding

Data on use during pregnancy and breast-feeding are limited or absent; it is not known whether macrogol 4000 passes into breast milk. According to the Summary of Product Characteristics, Fortrans should not be used during pregnancy and breast-feeding unless necessary. If you are pregnant, breast-feeding or planning a pregnancy, ask your doctor for advice before use.

Driving and using machines

The medicine is not known to affect the ability to drive and use machines. However, after each dose you need access to a toilet for as long as the medicine is working, so plan not to travel or drive during that time.

Possible side effects

• Expected effect: frequent bowel movements (diarrhoea) – this is normal and shows that the medicine is working.
• Very common (more than 1 in 10): nausea, abdominal pain, bloating.
• Common (up to 1 in 10): vomiting. Nausea and vomiting usually occur at the start and pass as you continue drinking the solution.
• Not known: allergic reactions – rash, hives, itching, angioedema, anaphylactic shock.

Stop taking it and contact your doctor immediately if you develop a serious allergic reaction. Report suspected side effects to your doctor, pharmacist or ALIMS.

Overdose, missed dose and stopping treatment

• Overdose: if you think you have taken too much, tell your doctor and drink enough water or clear fluid to avoid dehydration. According to the SmPC, higher doses can cause severe diarrhoea, electrolyte disturbance (low sodium and potassium), dehydration and hypovolaemia; in rare severe cases intravenous rehydration is given.
• Missed dose and stopping: according to the leaflet not applicable – the medicine is used once for bowel preparation. If you have not drunk the full prescribed amount of solution, inform the facility performing the examination.

Related information

You will receive a detailed preparation schedule (diet before the examination, timing of the solution and of your regular medicines) from your doctor or the facility performing the examination; for further questions about the medicine, ask a pharmacist.

Composition, pack and manufacturer

• Active substances (one sachet, 73.69 g powder): macrogol 4000 64.00 g; sodium sulfate, anhydrous 5.70 g; sodium hydrogen carbonate 1.68 g; sodium chloride 1.46 g; potassium chloride 0.75 g.
• Excipient: saccharin sodium. One sachet contains 2.890 g of sodium.
• Appearance and pack: white powder, readily soluble in water; polyethylene/aluminium/paper sachet; 4 sachets per carton.
• Manufacturer: Beaufour Ipsen Industrie, Rue Ethe Virton, Dreux, France (leaflet 11/2024); per the 2025 ALIMS amendment decision: Mayoly Industrie, Dreux, France. Marketing authorisation holder: PharmaSwiss d.o.o. Beograd, Batajnički drum 5A, Belgrade.
• Authorisation: 000457336 2023 of 29 November 2024.

Storage

• This medicine does not require any special storage conditions.
• Use the prepared solution immediately, in line with the method of administration.
• Shelf life is 3 years; do not use after the expiry date stated on the carton and sachet.
• Keep out of the sight and reach of children. Return unused medicine to a pharmacy that collects unused medicines.

Frequently asked questions

How many litres of Fortrans do I need to drink?

The dose is about one litre of solution per 15–20 kg body weight, on average 3 to 4 litres (3–4 sachets, each dissolved in 1 litre of water). The exact amount and schedule are set by the doctor.

Can I drink Fortrans in the evening and the morning?

Yes. The leaflet provides for split dosing – 2 litres in the evening and 1–2 litres in the morning, or 3 litres in the evening and 1 litre in the morning – with the last glass drunk 3–4 hours before the procedure. It is also possible to drink it all in the evening, with a one-hour break after the first 2 litres.

When should I take my regular medicines?

Medicines taken by mouth should be taken more than 2 hours before you start drinking the solution, because the diarrhoea can flush them out of the bowel. For medicines such as digoxin, antiepileptics, anticoagulants and immunosuppressants, always agree the timing with your doctor.

Is it normal to feel sick?

Nausea, abdominal pain and bloating are very common and vomiting is common; they usually occur at the start and pass as you continue drinking. Sudden abdominal pain or rectal bleeding require urgent contact with a doctor.

Sources

• ALIMS – Summary of Product Characteristics, Fortrans®, powder for oral solution (SmPC, Serbian)
• ALIMS – Package leaflet, Fortrans®, powder for oral solution (PIL, Serbian)

Sources checked on: 25 October 2026.