Macrogol

1. Introduction

Macrogol, also known as polyethylene glycol (PEG), is an osmotic laxative used for the treatment of constipation and bowel cleansing before diagnostic procedures or surgery. It works by retaining water in the bowel, softening stools and increasing bowel movements.

2. Indications

  • Approved Indications:
    • Chronic constipation.
    • Faecal impaction.
    • Bowel preparation prior to colonoscopy or surgery.
  • Off-Label Uses:
    • Short-term relief of acute constipation.

3. Dosage

  • Chronic Constipation:
    • Adults and children ≥12 years: 1–3 sachets (each 13 g) daily, adjusted based on response.
    • Children (6 months to 12 years): 0.5–1 sachet daily, adjusted by weight.
  • Faecal Impaction:
    • Adults: Up to 8 sachets daily, dissolved in water, taken within 6 hours for up to 3 days.
    • Children: 2–8 sachets daily, depending on age and weight, over a period of up to 7 days.
  • Bowel Preparation:
    • Adults: 3–4 litres of macrogol solution (divided doses), taken the day before or morning of the procedure.

4. Administration

  • Dissolve each sachet in 125 mL of water (or as directed) and drink immediately.
  • For bowel preparation, follow the specific instructions provided with the product.
  • Maintain adequate fluid intake during treatment to prevent dehydration.

5. Forms Available

  • Sachets (powder for solution): 13 g (standard) and higher doses for bowel cleansing.

6. Side Effects

6.1. Common Side Effects

  • Bloating.
  • Abdominal discomfort or cramping.
  • Diarrhoea.

6.2. Less Common Side Effects

  • Nausea or vomiting.
  • Flatulence.

6.3. Rare but Serious Side Effects

  • Electrolyte imbalances (in high doses or prolonged use).
  • Allergic reactions (e.g., rash, swelling, difficulty breathing).

7. Warnings

  • Electrolyte Imbalance: High doses or prolonged use may lead to electrolyte disturbances; monitor in patients with renal impairment or on diuretics.
  • Faecal Impaction: Use cautiously in patients with severe abdominal pain or suspected bowel obstruction.

8. Precautions

  • Ensure proper hydration during treatment to avoid dehydration.
  • Use cautiously in elderly patients or those with a history of electrolyte imbalances.
  • Do not use for prolonged periods without consulting a healthcare provider.

9. Interactions

  • Drug-Drug Interactions:
    • Reduced absorption of oral medications taken close to the time of macrogol administration. Separate administration by at least 1–2 hours.
  • Drug-Food Interactions:
    • No significant interactions; can be taken with or without food.

10. Monitoring Parameters

  • Improvement in bowel movements or resolution of constipation.
  • Electrolyte levels (especially in prolonged or high-dose use).
  • Symptoms of dehydration or overuse (e.g., diarrhoea, fatigue).

11. Use in Children

  • Approved for use in children ≥6 months for constipation and faecal impaction. Dose adjustments are based on age and weight.

12. Use in Pregnancy

  • Category B: Considered safe for short-term use during pregnancy. Consult a doctor before use.

13. Use in Elderly

  • Safe for use but monitor for dehydration and electrolyte imbalances, particularly in frail or debilitated patients.

14. Use in Kidney Disease

  • Use cautiously in patients with renal impairment. Monitor for signs of electrolyte imbalances during prolonged or high-dose use.

15. Use in Liver Disease

  • Generally safe in liver impairment, as it is not systemically absorbed.

16. Patient Counselling Points

  • Dissolve the sachet in water as directed before consuming. Do not take the powder directly.
  • Drink plenty of fluids during treatment to maintain hydration.
  • For constipation, macrogol may take 1–2 days to produce a bowel movement.
  • Do not use for more than 7 days without consulting a doctor.
  • Inform your doctor if you experience severe bloating, diarrhoea, or persistent abdominal pain.

17. Table of Brand Names, Manufacturers, and Prices

Brand NameManufacturerPrice (USD)
MovicolNorgine$15–25 (20 sachets, 13 g)
MiralaxBayer$20–30 (14 doses, 17 g)
Generic MacrogolVarious manufacturers$10–20 (20 sachets, 13 g)

18. FAQs (15 Questions)

  1. What is macrogol used for?
    It is used to treat constipation, faecal impaction, and for bowel preparation before medical procedures.
  2. How does macrogol work?
    It retains water in the bowel, softening stools and promoting bowel movements.
  3. How long does macrogol take to work?
    It typically works within 1–2 days for constipation and within hours for bowel preparation.
  4. Can macrogol be used in children?
    Yes, it is approved for children ≥6 months, with doses adjusted by weight.
  5. Is macrogol safe during pregnancy?
    Yes, it is generally considered safe for short-term use during pregnancy.
  6. Can I take macrogol with other medications?
    Yes, but take other medications at least 1–2 hours before or after macrogol to avoid reduced absorption.
  7. What are common side effects of macrogol?
    Common side effects include bloating, abdominal discomfort, and diarrhoea.
  8. Can macrogol cause dehydration?
    Yes, especially if it leads to excessive diarrhoea. Drink plenty of fluids to stay hydrated.
  9. How should macrogol be taken?
    Dissolve the sachet in water as directed and drink immediately.
  10. Can macrogol be used long-term?
    Prolonged use should only be under medical supervision to avoid electrolyte imbalances.
  11. Does macrogol interact with other medications?
    It may reduce the absorption of other medications; separate dosing by 1–2 hours.
  12. Can macrogol cause electrolyte imbalances?
    Yes, particularly with high doses or prolonged use. Monitor potassium and sodium levels if used long-term.
  13. How should macrogol be stored?
    Store sachets in a cool, dry place, away from moisture and heat.
  14. Can I take macrogol with dairy products?
    Yes, macrogol does not interact with dairy products.
  15. What should I do if macrogol does not work?
    If constipation persists after 7 days, consult your doctor for further evaluation.