Patient leaflets and SmPCs, drug interaction checker, official dosages and NHS pharmacy opening hours — all in one place.
Patient leaflets and SmPCs, drug interaction checker, official dosages and NHS pharmacy opening hours — all in one place.
The electronic medicines compendium (emc) no longer publishes a Summary of Product Characteristics for this product, which usually means it is no longer marketed in the UK. The patient leaflet below is kept for reference, but the product may not be available.
If you were prescribed this medicine, other products containing Macrogol 4000 may still be available. Do not stop your treatment — ask your pharmacist or GP what to use instead.
FOR The name of this medicine is PEGLAX, powder for oral solution in sachet. PEGLAX is considered as osmotic laxative. PEGLAX is used for the symptomatic treatment of constipation in adults and children 8 years old and over. It should be used with appropriate changes to lifestyle and diet (see section 2).
You must talk to a doctor if you do not feel better or if you feel worse. This medicine contains Macrogol (P.E.G. = polyethylene glycol). In the case of constipation, the maximum treatment period in children is 3 months
E PEGLAX Occasional constipation: Occasional constipation may be related to a recent change in your lifestyle. There are
medicines that can be used for short term treatment. Ask the opinion of your doctor in the case of recent constipation which cannot be explained by changes in your lifestyle, or in the case of constipation associated with pain, fever or abdominal swelling.
Chronic constipation (long term constipation): Chronic constipation may be caused by:
If you are allergic to Macrogol (P.E.G. = polyethylene glycol) or any of the other ingredients of this medicine (listed in section 6).
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If you have any intestine or colon disease (such as ulcerative colitis, Crohn's disease). If you have abdominal pain of undetermined cause. If you have or suspect a gastrointestinal perforation. If you have or suspect a bowel obstruction
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Warnings and Precautions Talk to your doctor, pharmacist or nurse before taking PEGLAX. If you develop diarrhoea following treatment with PEGLAX you may be at risk of developing electrolytec disorders (a decrease in certain salts in the blood). You are more likely to be at risk if you are an older person, or have liver or kidney problems, or are taking diuretics (water tablets). If you are one of these people and you develop diarrhoea you should see your doctor to have your electrolyte levels checked with a blood test. Children Ask your doctor ́s opinion before administering this treatment to your child, in order to exclude any organic cause of constipation. After 3 months of treatment, your doctor should evaluate your child clinical condition. Other medicines and Casenlax. PEGLAX may delay the absorption of other medicines, making them less effective or ineffective especially those with a narrow therapeutic index (e.g antiepileptics, digoxin and immunosuppressive agents). Tell your doctor or pharmacist if you are taking, have recently taken or might take any other medicines.
Pregnancy and breast-feeding If you are pregnant or breast-feeding, think you may be pregnant or are planning to have a baby, ask your doctor or pharmacist for advice before taking this medicine Pregnancy PEGLAX can be used during pregnancy. Breast-feeding PEGLAX can be used during breast-feeding. Driving and using machines PEGLAX has no influence on ability to drive and use machines. PEGLAX contains sulphur dioxide. This medicine may rarely cause severe hypersensitivity reactions and bronchospasm (difficulty breathing) because of its sulphur dioxide content. PEGLAX contains sodium This medicine contains less than 1 mmol sodium (23 mg) per sachet that is to say essentially "sodium- free". PEGLAX contains a non-significant amount of sugar or polyol and thus may be prescribed to diabetic patients or patients on a galactose-free diet.
PEGLAX Always take PEGLAX exactly as your doctor or pharmacist has told you. Check with your doctor or pharmacist if you are not sure. For oral use. The usual dose is: The recommended dose is: 1 to 2 sachets per day, preferably taken as a single dose in the morning. It is recommended to drink 125 ml of liquids (e.g. water) after each dose. The daily dose should be adjusted according to the clinical effects obtained and may range from one sachet every other day (especially in children) to up to a maximum of 2 sachets per day. The effect of PEGLAX occurs within 24 to 48 hours after administering.
Dissolve the content of the sachet in a glass of water (at least 125 ml) immediately before use and drink the liquid.
Improvement in the frequency of your bowel movements after taking Casenlax can be maintained by keeping to a healthy lifestyle and diet. Use in children and adolescents
For children, the treatment must not exceed 3 months due to a lack of clinical data from more than 3 months treatments. Treatment should be stopped gradually and resumed if constipation recurs. If you take more PEGLAX than you should You can develop diarrhoea, abdominal pain and vomiting which disappears when treatment is temporarily interrupted or the dose is reduced. If you suffer from severe diarrhoea or vomiting you should contact a doctor as soon as possible as you may require treatment to prevent loss of salts (electrolytes) from fluid loss. If you forget to take PEGLAX Do not take a double dose to make up for a forgotten dose.
4. POSSIBLE SIDE EFFECTS Like all medicines, this medicine can cause side effects, although not everybody gets them. The most serious side effects are considered to be the allergic (hypersensitivity) reactions that include pruritus (itchy rash), rash, face oedema (swelling of the face), quincke oedema (rapid swelling of the deep layers of the skin), urticaria (nettle rash) and anaphylactic shock. Its frequency has been reported as very rare (may affect up to 1 in 10,000 people) in adult population and as unknown (frequency cannot be estimated from available data) in paediatric population. If you notice any of the reactions listed above, please stop taking this medicine immediately and seek urgent medical advice. Adults: Generally, adverse reactions have been minor and transitory and have mainly concerned the gastrointestinal system. These side effects include: Common (may affect up to 1 in 10 people) • • • •
Abdominal pain Abdominal distension Diarrhoea Nausea
Uncommon (may affect up to 1 in 100 people) • • •
Vomiting Urgency to defecate Faecal incontinence
Not known (frequency cannot be estimated from available data) • • •
Electrolyte disorders (low blood levels of sodium and potassium: hyponatremia, hypokalemia) Dehydration, caused by severe diarrhoea especially in elderly patients Erythema
Children/adolescents: As in adult population, adverse reactions have generally been minor and transitory and have mainly concerned the gastrointestinal system. These side effects include: Common (may affect up to 1 in 10 people) • •
Abdominal pain Diarrhoea (may cause perianal soreness)
Uncommon (may affect up to 1 in 100 people) • • •
Vomiting Bloating Nausea
Excessive doses can cause diarrhoea, abdominal pain and vomiting which disappears generally when the dose is reduced or treatment temporarily interrupted. Reporting of side effects If you get any side effects, talk to your doctor, pharmacist or nurse. This includes any
not listed in this leaflet. You can also report side effects directly via the Yellow Card Scheme. Website: www.mhra.gov.uk/yellowcard or search for MHRA Yellow Card in the Google Play or Apple App Store. By reporting side effects you can help provide more information on the safety of this medicine.
PEGLAX Keep this medicine out of the sight and reach of children. This medicine does not require special storage conditions.
Do not use this medicine after the expiry date which is stated on the sachet/outer carton after EXP. The expiry date refers to the last day of that month. Do not use this medicine if you notice any visible signs of deterioration. Do not throw away any medicines via wastewater or household waste. Ask your pharmacist how to throw away medicines you no longer use. These measures will help protect the environment.
What PEGLAX contains The active substance is: Macrogol 4000 Each sachet contains 10g of macrogol 4000. The other ingredients are: Saccharin sodium (E954) and Apple flavour (Natural flavour, maltodextrine, gum arabic E414, sulphur dioxide E220, alpha tocopherol E307). See section 2 "Casenlax contains sulphur dioxide" What PEGLAX looks like and contents of the pack PEGLAX is an almost white powder in a sachet for making up a solution. It is available in packs of 8, 10, 20, 30, 50, 60 or 100 sachets. Not all pack sizes may be marketed. Marketing Authorisation Holder and Manufacturer Casen Recordati, S.L. Autovía de Logroño, Km 13,300 50180 UTEBO. Zaragoza (Spain) This medicine is authorized in the Member States of EEA under the following names: Bulgaria: Касенлакс 10 g прах за перорален разтвор в саше Belgium: Transilax 10 g Cyprus: Macrogol 4000 Casen Recordati 10 g κόνις για πόσιμο διάλυμα σε φακελίσκο Denmark: Casenlax 10g pulver til oral opløsning i brev Estonia: Proctolax Finland: Casenlax 10g jauhe oraaliliuosta varten, annospussi France: Casenlax 10g poudre pour solution buvable Germany: Laxbene 10 g Pulver zur Herstellung einer Lösung zum Einnehmen, in Beuteln, für Kinder ab 8 Jahren und Erwachsene Greece: Cleenlax forte 10 g κόνις για πόσιμο διάλυμα σε φακελίσκο
Ireland: PEGLax 10g Powder for oral solution in sachet Italy: Casenlax 10g polvere per soluzione orale in bustina Latvia: Proctolax 10 g pulveris iekšķīgi lietojama šķīduma pagatavošanai paciņā Lithuania: Macrogol 4000 Casen Recordati 10 g milteliai geriamajam tirpalui paketėlyje Luxembourg: Transilax 10 g Netherlands: Casenlax 10 g poeder voor drank Norway: Casenlax 10g pulver til mikstur, oppløsning i dosepose Portugal: Casenlax 10g pó para solução oral em saquetas Romania: Proctolax 10g, pulbere pentru soluție orală, in plic Spain: Casenlax 10g polvo para solución oral en sobre Sweden: Casenlax 10g pulver till oral lösning i dospåse
United Kingdom (Northern Ireland): PEGLax 10g Powder for oral solution in sachet This leaflet was last revised in: April 2025
PegLax 10 g powder for oral solution in sachet comes as oral solution containing 10g. Always follow the dose your doctor or pharmacist has given you, and read the leaflet that comes with the medicine.
The active substance in PegLax 10 g powder for oral solution in sachet is macrogol 4000.
This leaflet reproduces the patient information leaflet approved for PegLax 10 g powder for oral solution in sachet, as published on the electronic medicines compendium (emc). The version printed inside your medicine’s packaging is the one that applies to you.
Whether a medicine is available over the counter or on prescription only depends on its licence. Check the leaflet, or ask your pharmacist — they can tell you straight away.
The text above reproduces the patient information leaflet approved for this medicine, restructured for easier reading.
Symptomatic treatment of constipation in adults and children aged 8 years and above.
An organic disorder should have been ruled out before initiation of treatment PEGLAX 10 g should remain a temporary adjuvant treatment to appropriate lifestyle and dietary management of constipation, with a maximum 3-months treatment course in children. If symptoms persist despite associated dietary measures, an underlying cause should be suspected and treated
Oral use
Posology
1 to 2 sachets per day, preferably taken as a single dose in the morning. It is recommended to drink 125 ml of liquids (e.g. water) after each dose.
The effect of Peglax becomes apparent within 24 to 48 hours after its administration.
The daily dose should be adapted according to the clinical effects and may range from one sachet every other day (especially in children) up to 2 sachets a day.
Treatment should be stopped gradually and resumed if constipation recurs.
Paedriatic population
1 to 2 sachets per day, preferably taken as a single dose in the morning. It is recommended to drink 125 ml of liquids (e.g. water) after each dose.
In children, treatment should not exceed 3 months due to a lack of clinical data for treatment lasting longer than 3 months. Treatment-induced restoration of bowel movements will be maintained by lifestyle and dietary measures.
Method of administration
Each sachet should be dissolved in a glass of water (125 ml approximately) just before use. The resultant solution will be clear and transparent like water.
- Hypersensitivity to the active substance or to any of the excipients listed in section 6.1.
- Severe inflammatory bowel disease (such as ulcerative colitis, Crohn's disease) or toxic megacolon, associated with symptomatic stenosis,
- Digestive perforation or risk of digestive perforation,
- Ileus or suspicion of intestinal obstruction,
- Painful abdominal syndromes of indeterminate cause.
The treatment of constipation with any medicinal product is only an adjuvant to a healthy lifestyle and diet, for example:
- Increased intake of liquids and dietary fibre,
- Appropriate physical activity and rehabilitation of the bowel reflex.
Due to the presence of sulphur dioxide, Peglax may rarely cause severe hypersensitivity reactions and bronchospasm.
In case of diarrhoea, caution should be exercised in patients who are prone to a disturbance of water and/or electrolyte balance (e.g. the elderly, patients with impaired hepatic or renal function or patients taking diuretics) and electrolyte control should be considered.
Hypersensitivity reactions (rash, urticaria, and oedema) have been reported with drugs containing macrogol (polyethylene glycol) Exceptional cases of anaphylactic shock have been reported.
Peglax contains a non-significant amount of sugar or polyol and thus may be prescribed to diabetic patients or patients on a galactose-free diet.
This medicine contains less than 1 mmol sodium (23 mg) per sachet that is to say essentially “sodium- free”.
According to the way of action of macrogol, it is recommended to intake liquids during the treatment with this medicine (please see section 5.1).
The absorption of other medicinal products could transiently be reduced due to an increase in gastro-intestinal transit rate induced by macrogol (see section 4.5).
There is a possibility that the absorption of other medicinal products could be transiently reduced during use with Peglax. The therapeutic effect of medicinal products with a narrow therapeutic index may be particularly affected (e.g antiepileptics, digoxin and immunosuppressive agents).
Pregnancy
Animal studies do not indicate direct or indirect harmful effects with respect to reproductive toxicity (see section 5.3).
There are limited amount of data (less than 300 pregnancy outcomes) for the use of Peglax in pregnant women.
No effects during pregnancy are anticipated, since systemic exposure to Peglax is negligible. Peglax can be used during pregnancy.
Lactation
There are no data on the excretion of Peglax in breast milk. No effects on the breast fed newborn/infant are anticipated since the systemic exposure of the breast-feeding woman to macrogol 4000 is negligible. Peglax can be used during breast feeding.
Fertility:
No fertility studies were conducted with Peglax however since macrogol 4000 is not significantly absorbed no effects are anticipated.
Peglax has no influence on ability to drive and use machines.
Undesirable effects are listed under headings of frequency using the following categories:
Very common (≥1/10); common (≥1/100 to <1/10); uncommon (≥1/1,000 to <1/100); rare (≥1/10,000 to <1/1,000); very rare (<1/10,000); not known (cannot be estimated from the available data).
Adult population:
The undesirable effects listed in the table below have been reported during clinical trials (including 600 adult patients) and post-marketing use. Generally, adverse reactions have been minor and transitory and have mainly concerned the gastrointestinal system:
System Organ Class
Adverse reactions
Immune system disorders
Very rare
Hypersensitivity reactions (Pruritus, Rash, Face oedema, Quincke oedema, Urticaria, Anaphylactic shock)
Not known
Erythema
Metabolism and Nutrition Disorders
Not known
Electrolytes disorders (Hyponatremia, Hypokalaemia) and or dehydration, especially in elderly patients
Gastrointestinal disorders
Common
Abdominal pain and/ or distension
Diarrhoea
Nausea
Uncommon
Vomiting
Urgency to defecate
Fecal incontinence
Paediatric population:
The undesirable effects listed in the table below have been reported during clinical trials including 147 children aged from 6 months to 15 years and post-marketing use. As in adult population, adverse reactions have generally been minor and transitory and have mainly concerned the gastrointestinal system:
System Organ Class
Adverse reactions
Immune system disorders
Not known
Hypersensitivity reactions (Anaphylactic shock, Angioedema, Urticaria, Rash, Pruritus)
Gastrointestinal disorders
Common
Abdominal pain
Diarrhoea*
Uncommon
Vomiting
Bloating
Nausea
* Diarrhoea may cause perianal soreness
Reporting of suspected adverse reactions
Reporting suspected adverse reactions after authorisation of the medicinal product is important. It allows continued monitoring of the benefit/risk balance of the medicinal product. Healthcare professionals are asked to report any suspected adverse reactions via the Yellow Card Scheme. Website: www.mhra.gov.uk/yellowcard or search for MHRA Yellow Card in the Google Play or Apple App Store.
Overdose could lead to diarrhoea, abdominal pain and vomiting which disappears when treatment is temporarily interrupted or the dosage is reduced.
Excessive fluid loss by diarrhoea or vomiting may require correction of electrolyte disturbances
Cases of aspiration have been reported when extensive volumes of macrogol (polyethylene glycol) and electrolytes were administered with nasogastric tube. Neurologically impaired children who have oromotor dysfunction are particularly at risk of aspiration.
Medicines sold in Romania with the same active substance: Cunoscut în România ca
Same active substance. The strength, the form and whether you need a prescription can differ. Always ask a pharmacist before you switch. Romanian medicines in the UK →
Medicines sold in Poland with the same active substance: W Polsce znany jako
Same active substance. The strength, the form and whether you need a prescription can differ. Always ask a pharmacist before you switch. Polish medicines in the UK →
Ask anything about PegLax 10 g powder for oral solution in sachet. The assistant answers only from this leaflet — if the leaflet does not cover it, it will say so. It does not give medical advice.
Answers come from the patient leaflet published on the electronic medicines compendium (emc). They are not medical advice. Ask a pharmacist or your GP if you are unsure. For urgent help call NHS 111, or 999 in an emergency.
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