Polyethylene Glycol is an osmotic laxative used for occasional and chronic constipation in adults and children. It is a large, inert polymer that is not absorbed in the gastrointestinal tract. Instead, it stays in the colon, where it binds water and increases the water content of stool. This softens the stool, increases its volume, and gently stimulates a bowel movement without cramping or urgency. Polyethylene Glycol is widely used as a once-daily oral powder dissolved in water and is a common laxative recommended for constipation.

Polyethylene Glycol is supplied as a tasteless, odourless powder in single-dose sachets or bottles with measuring caps. It is taken orally after dissolving in water, juice, or another beverage. The medicine is intended for short-term relief of occasional constipation and is also used long-term for chronic constipation under medical supervision.

Polyethylene Glycol is a polyether polymer that is too large to be absorbed across the intestinal wall and is excreted unchanged in the stool. Because it is biologically inert and does not affect electrolytes, glucose, or hormones, it has a favourable safety profile and is suitable for prolonged use in adults, the elderly, and children under medical supervision.

It is generally well tolerated and does not cause significant gas, bloating, or cramping at standard doses. This makes it different from older laxatives such as lactulose or stimulants like bisacodyl and senna. Many recommend polyethylene glycol as a first-line option for chronic constipation and faecal impaction in adults and children.

Occasional constipation

Short-term relief from irregular, hard stools, or straining.

Chronic constipation

Long-term treatment for adults and children suffering from constipation for a long time.

Faecal impaction in children

Disimpaction therapy and ongoing maintenance.

Opioid-induced constipation

Used as a stool softener.

Constipation in pregnancy

Considered safe due to lack of systemic absorption (after specialist advice).

Constipation in older adults

Preferred laxative due to its gentle action and minimal side effect profile.

• Increases bowel movement frequency, softens stool, and reduces straining.

• Unlike other laxatives, Polyethylene Glycol does not cause cramping, urgency, or electrolyte disturbances at standard doses.

• Not absorbed systemically, with extremely low risk of systemic side effects.

• Safe for long-term use under medical supervision.

• Tasteless and odourless powder mixes well in water, juice, tea, or coffee.

• Suitable for adults, the elderly, and children under medical guidance.

• Once-daily dosing improves adherence.

• Does not cause habit formation or rebound constipation, unlike stimulant laxatives.

Common (especially during the first week):

• Bloating and mild abdominal cramps

• Gas (flatulence)

• Nausea

• Loose stools or mild diarrhoea

• Increased bowel movement frequency

Uncommon:

• Watery diarrhoea usually happens when higher than recommended doses are consumed

• Mild dehydration if fluid intake is inadequate

• Anorectal soreness (rectal pain) with frequent visits to pass stool

• Headache

Serious side effects requiring immediate attention:

• Severe diarrhoea with dehydration or electrolyte imbalance

• Severe abdominal pain or persistent cramping

• Rectal bleeding or blood in the stool

• Severe allergic reactions, including hives, swelling, or difficulty breathing

• Symptoms of bowel obstruction, such as abdominal distension (enlargement of the abdomen), persistent vomiting, or inability to pass stool or gas

Consume Polyethylene Glycol as directed by your doctor. Add the suggested amount of powder to water, juice, or another beverage, stir until it completely dissolves and consume this mix once daily. The powder is generally tasteless and can be mixed with hot or cold drinks. For children, the dose is calculated by weight and should be prescribed by a doctor. Higher doses may be used for faecal disimpaction in children for a few days. The onset of bowel movement is usually within 24 to 72 hours. For occasional constipation, Polyethylene Glycol should not be used for more than a week without consulting a doctor. For chronic constipation, longer use under medical supervision is appropriate. Drink adequate water throughout the day to prevent dehydration. The dosage can be reduced once a regular pattern of soft stools is established. Do not exceed the prescribed dose without consulting your doctor.

Constipation happens when stool moves too slowly through the colon (the longest part of the large intestine), allowing too much water to be absorbed by the intestinal wall. The result is hard, dry, difficult-to-pass stools and fewer bowel movements. Polyethylene Glycol addresses this by acting as an osmotic agent in the colon.

Polyethylene Glycol is a long, inert polymer that is too large to be absorbed across the intestinal wall. After ingestion, it travels through the small intestine and into the colon largely unchanged. Each polyethylene glycol molecule has many oxygen atoms along its chain that form hydrogen bonds with water in the gut. As a result, Polyethylene Glycol holds onto water and prevents it from being absorbed by the colonic wall.

The retained water remains in the stool, increasing its volume and softening it. The volume of the stool gently stretches the wall of the colon, generating natural movement of the colon (peristalsis) and producing a bowel movement. Because the laxative effect comes from physical water retention rather than chemical irritation, polyethylene glycol does not cause the cramping, urgency, or bowel-wall damage seen with stimulant laxatives.

Unlike osmotic sugars (lactulose, sorbitol), which are fermented by colonic bacteria and produce gas and bloating, Polyethylene Glycol is not fermented and produces minimal gas. Unlike saline laxatives like magnesium hydroxide, it does not cause electrolyte shifts, making it safer for patients with kidney or heart problems.

• Food (NIL): Can be taken with or without food.

• Alcohol (NIL): No clinically significant interaction. However, alcohol consumption may worsen dehydration.

• Other beverages (NIL): Can be mixed with water, juice, tea, or coffee without affecting efficacy.

Other oral medications

USE WITH CAUTION

Can accelerate transit and reduce the absorption of drugs taken at the same time. Separate by 1 to 2 hours where possible.

Diuretics

USE WITH CAUTION

Combined use may increase the risk of dehydration and electrolyte imbalance.

Other laxatives

MODERATE

Combination is generally unnecessary and may cause excessive diarrhoea.

Antidiarrhoeal drugs (loperamide)

USE WITH CAUTION

Counteract each other; do not combine.

Note: Polyethylene glycol is not absorbed and does not affect drug-metabolising enzymes. Pharmacokinetic interactions are minimal.

• Bowel obstruction or suspected obstruction (AVOID): Polyethylene Glycol draws water into the gut, increasing pressure behind the blockage and risking perforation.

• Bowel perforation (AVOID): Pushing more fluid and stool through a hole in the bowel wall accelerates peritonitis and sepsis.

• Severe inflammatory bowel disease (USE WITH CAUTION): The inflamed, friable bowel wall can worsen under added osmotic and motility stress.

• Toxic megacolon (AVOID): Any added volume can trigger perforation.

• Ileus or impaired GI motility (AVOID): Without bowel contractions, the drawn-in fluid just accumulates, causing distension and vomiting.

• Phenylketonuria (PKU) (USE WITH CAUTION): A few formulations contain aspartame, which breaks down into phenylalanine that PKU patients can't process. Check the label before use.

Overdosage of Polyethylene Glycol may result in severe diarrhoea, abdominal cramping, dehydration, and electrolyte disturbances such as hyponatraemia (low sodium) or hypokalaemia (low potassium). Management may include stopping Polyethylene Glycol, replacing fluids and electrolytes orally or intravenously, and monitoring electrolyte levels and hydration status. Symptoms generally resolve within 12 to 24 hours of stopping the drug. Severe cases, especially in children, the elderly, or patients with cardiac or renal disease, should be managed by a healthcare professional.

If you've missed a dose, take is as soon as you remember on the same day, unless it is close to the time of the next dose. In this case, skip it and continue with your normal schedule. Do not double-dose, as this can cause excessive bowel movements and dehydration. For chronic constipation, consistent daily use is more important than occasional missed doses.