Fybogel (ispaghula husk)

  1. About Fybogel

    Fybogel is a laxative taken to treat constipation (difficulty pooing).

    It comes as plain or fruit-flavoured granules that you mix with water to make a high-fibre drink.

    Fybogel is available on prescription and to buy from pharmacies and supermarkets.

  2. Key facts

    • Fybogel is a high-fibre drink that you take in the morning and evening, preferably after a meal.
    • Fybogel takes 2 or 3 days to work.
    • When taking this type of laxative make sure you drink plenty of fluids.
    • The main side effects are wind and bloating.
    • Fybogel is also called ispaghula husk and Ispage.
  3. Who can and can't take Fybogel

    Fybogel can be taken by adults including pregnant and breastfeeding women.

    Fybogel can be taken by children aged 6 years and older. Do not give Fybogel to a child under 6 years unless your doctor has said it's ok.

    Fybogel isn't suitable for everyone. To make sure Fybogel is safe for you, tell your doctor or pharmacist if you have:

    • had an allergic reaction to Fybogel or any other medicines in the past
    • a bowel obstruction
    • muscle weakness of the bowel (colonic atony)
    • a rare genetic illness called phenylketonuria
  4. How and when to take it

    Fybogel comes as sachets of plain, orange or lemon-flavoured granules. It's best to take Fybogel after a meal or snack.

    How much should I take?

    The normal dose for constipation in:

    • adults and children aged 13 years and over is 1 sachet of Fybogel granules twice a day
    • children aged 6 to 12 years is ½ to 1 level 5ml spoonful of Fybogel granules twice a day
    • children under the age of 6 years (only under medical supervision) is ½ to 1 level 5ml spoonful of Fybogel granules twice a day

    How to take it

    To make up the medicine, open the sachet and empty the granules into a glass. Add at least 150mls (1/4 pint) of cold water to the glass. Stir well until all the granules have dissolved and the Fybogel solution is clear or slightly hazy, and then drink it straight away.

    Try not to breathe in the powder when you make up the Fybogel drink as it can occasionally trigger a mild allergic reaction.

    Have your evening drink of Fybogel at least an hour before going to bed. Drinking Fybogel just before you go to sleep increases the chances of it causing a blockage in the gut.

    Aim to drink 6 to 8 glasses of fluid during the day while you are taking Fybogel or the constipation may get worse.

    What if I forget to take it?

    If you forget a dose of Fybogel, don't worry, just take the next dose at the usual time.

    Never take 2 doses at the same time. Never take an extra dose to make up for a forgotten one.

    What if I take too much?

    Taking too much Fybogel by accident is unlikely to harm you. If this happens, drink plenty of water.

    If you're worried, talk to your doctor or pharmacist for advice.

  5. Side effects

    Like all medicines, Fybogel may cause side effects in some people, but many people have no side effects or only minor ones.

    Common side effects

    The most common side effects, which happen in more than 1 in 100 people, are wind and bloating. This sometimes happens because of the sudden increase of fibre in your diet. It should get better after a few days.

    If the side effects carry on, or if you are worried, talk to your doctor or pharmacist.

    Mild allergic reaction

    It's possible to have a mild allergic reaction such as itchy eyes, nose or skin.

    You're more likely to have a mild allergic reaction to Fybogel if you've had an allergic reaction before and if you're exposed to the powder regularly, for example if you're a carer.

    If you think you are having a mild allergic reaction to Fybogel, stop taking it and ask your pharmacist or doctor for advice.

    Serious allergic reaction

    In rare cases, it’s possible to have a serious allergic reaction to Fybogel.

    A serious allergic reaction is an emergency. Contact a doctor straight away if you think you or someone around you is having a serious allergic reaction.

    The warning signs of a serious allergic reaction are:

    • getting a skin rash that may include itchy, red, swollen, blistered or peeling skin
    • wheezing
    • tightness in the chest or throat
    • having trouble breathing or talking
    • swelling of the mouth, face, lips, tongue, or throat

    These are not all the side effects of Fybogel. For a full list see the leaflet inside your medicines packet.

    You can report any suspected side effect to the UK safety scheme.

  6. Pregnancy and breastfeeding

    Fybogel is generally safe to take during pregnancy and while breastfeeding.

    For safety, tell your pharmacist or doctor if you're trying to get pregnant, are already pregnant or if you're breastfeeding.

  7. Cautions with other medicines

    Fybogel can change the way some medicines work. Tell your doctor if you are taking these medicines before starting Fybogel:

    • carbamazepine (a medicine for epilepsy and mood problems)
    • digoxin (a heart medicine)
    • mesalazine (a medicine to treat gut problems)

    There is some evidence that Fybogel stops iron being taken in properly by the body. If you need iron supplements, it's best to take them at least 1 hour before, or 4 hours after, you take Fybogel.

    Mixing Fybogel with herbal remedies and supplements

    There are no known problems with taking herbal remedies and supplements with Fybogel.

    However, for safety, tell your doctor or pharmacist if you're taking any other medicines, including herbal remedies, vitamins or supplements.

  8. Common questions