Macrogol sachets
Macrogol sachets, which are most commonly used. Brand names include Movicol and Laxido. These contain macrogol 3350 plus salts (also called electrolytes). They’re usually the first-line treatment because they’re effective and well-tolerated.
- It’s an osmotic laxative that works by drawing water into the bowel, which softens the poo and makes it easier to pass.
- Typically, you’ll be advised to mix one sachet with water and drink it, and take it once or multiple times a day, depending on the severity of the constipation.
- They generally work within 6 to 48 hours.
- Most brands are basically the same in terms of effectiveness, but may differ in taste and cost.
- It’s suitable for most people, but not if you follow a low-salt diet, have heart problems, Crohn’s, a blockage in your intestines, or have had an allergic reaction to macrogol.
Fibre-based sachets
Fibre-based sachets like Fybogel or YourFibre, which contain ispaghula husk (also known as psyllium).
- They work by increasing stool bulk, which stimulates bowel movement.
- They need to be taken with plenty of fluid and usually take two to three days to work.
- They’re best for mild constipation.
- Most adults can take them, including pregnant and breastfeeding women, but they may not be the right treatment for you if you have a blockage in your bowel, muscle weakness of the bowel, difficulty swallowing, a rare genetic condition called called phenylketonuria, changes in your poo that have lasted longer than two weeks.
- Lactulose is also available as sachets containing liquid that you drink.
- It works similarly to macrogol, but can cause bloating and wind, which makes it less effective for patients suffering from conditions like irritable bowel syndrome (IBS). Also, compared to lactulose, patients treated with macrogol were 35% more likely to be successfully treated for long-term constipation at three months.
- Takes two to three days to start working.
- It’s suitable for most patients, including pregnant and breastfeeding women.
- It’s not suitable if you have diabetes.
Senna
Senna is usually available as a tablet, but can also be found in sachet form, either on its own (usually as tea bags), or in combination with other laxatives like ishpagula husk.
- It’s a stimulant laxative, acting by directly stimulating your bowel movements. It’s also called a ‘motility enhancer’ sometimes.
- Tends to work within 8 to 12 hours, making it more suitable for short-term or ‘rescue' use or to empty your bowels before surgery.
- It’s suitable for most people, including children (with a prescription), but not suitable if you have severe stomach pain, show signs of dehydration, have Crohn’s disease, kidney disease, or heart problems, are pregnant or breastfeeding.
