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Mebeverine hydrochloride with ispaghula husk


Granules for oral suspension containing 3.5g ispaghula husk with 135mg mebeverine hydrochloride in a unit dose sachet.

Drugs List

  • FYBOGEL MEBEVERINE effervescent granules
  • ispaghula husk 3.5g and mebeverine 135mg effervescent granules sugar-free
  • Therapeutic Indications


    Symptomatic relief of irritable bowel syndrome.



    One sachet morning and evening, taken half an hour before meals. A third dose may be taken before the midday meal if necessary.


    No dosage adjustment necessary (see 'Dosage; Adults' section)


    Contraindicated in children under 12 years of age


    No dosage adjustment necessary (see 'Dosage; Adults' section)


    For oral administration

    The contents of one sachet should be stirred into a 150ml glass of cold water and drunk immediately.


    Children under 12 years of age

    Intestinal obstruction , paralytic ileus, faecal impaction and colonic atony

    Hereditary fructose intolerance

    Hypersensitivity to arachis oil

    Phenylketonuria: contains aspartame

    Precautions and Warnings

    Pregnancy - see 'Pregnancy' section.

    Ensure patient takes product with stated amount of fluid and to take continue additional fluid intake.

    Risk of hyperkalaemia in those taking potassium supplements or potassium sparing diuretics as each sachet contains 7mmol of potassium.

    Advise patient to contact their doctor if, after two weeks, their symptoms do not improve despite treatment.

    Advise patient to contact their doctor if their symptoms of IBS have changed.

    Contains sucrose, therefore do not use in hereditary fructose intolerance and use with caution in glucose-galactose malabsorption syndrome.

    This product contains soybean oil, therefore do not use in patients with hypersensitivity to arachis oil.

    Prior review by a physician is essential before use in the following patient groups:
    - those over 40 years of age
    - those positive for rectal bleeding or hematochezia
    - those with active nausea or vomiting
    - those with decreased appetite or weight loss evident
    - those pale appearance and tired
    - those positive for elevated temperature and fever
    - those positive for constipation
    - those recently travelled abroad
    - those who are or may be expecting
    - those experiencing menorrhagia, metrorrhagia or menometrorrhagia
    - those with micturition pain
    - those taking diuretic therapy or on a potassium supplemented diet
    - those with acute porphyria

    Use in Porphyria

    Although the manufacturer advises caution in patients that have acute porphyria, The Drug Database for Acute Porphyria, compiled by the Norwegian Porphyria Centre (NAPOS) and the Porphyria Centre Sweden, classifies mebeverine as probably not porphyrinogenic; it may be used as a drug of first choice and no precautions are needed.

    Pregnancy and Lactation


    Use with caution in pregnancy.

    There have been no detailed studies on the use of mebeverine during pregnancy.

    Ispaghula is not absorbed by the gastrointestinal tract.

    The use of all medication in pregnancy should be avoided whenever possible; particularly in the first trimester. Non-drug treatments should also be considered. When essential, a medication with the best safety record over time should be chosen, employing the lowest effective dose for the shortest possible time. Polypharmacy should be avoided. Teratogens taken in the pre-embryonic period, often quoted as lasting until 14-17 days post-conception, are believed to have an all-or-nothing effect. Where drugs have a short half-life, and when the date of conception is certain, this may allow women to be reassured where drug exposure has occurred within this time frame. Further advice may be available from the UK National Teratology Information Service (NTIS) and through ToxBase, available via password on the internet ( ) or if this is unavailable at the backup site ( ).


    There is no contraindication to use during breastfeeding. Mebeverine is excreted in breast milk but in quantities too small to be harmful to the infant and ispaghula husk is not absorbed by the gastrointestinal tract.

    Neonates, infants born prematurely, those with low birth weight, those with an unstable gastrointestinal function or who have serious illnesses may require special consideration. For any infant, if a drug is prescribed to the nursing mother, it should be at the lowest practical dose and for the shortest time. When drug administration is unavoidable and breastfeeding is to continue, minimisation of exposure of the infant to the drug may sometimes be achieved by timing the maternal doses to just after a feeding episode. Infants exposed to drugs via breast milk should be monitored for unusual signs or symptoms. Interactions between the drug received by the infant from the mother's milk and medication prescribed for the infant should also be considered, for example, when the drug given to the infant may prevent metabolism of the drug received via breast milk.
    Specialist advice is available from the UK Drugs in Lactation Advisory Service at

    Effects on Ability to Drive and Operate Machinery

    None known


    Advise patient to take product with stated amount of 150ml fluid.

    Advise patient to contact their doctor if, after two weeks, their symptoms do not improve despite treatment.

    Advise patient to contact their doctor if their symptoms of IBS have changed.

    Advise patient to take continue additional fluid intake.

    Advise patient to take 30 minutes before food.

    Advise patient that the preparation is likely to swell when in contact with water, so should be swallowed carefully and not taken immediately before going to bed.

    Advise patient not to take other medicines one hour before or after this medicine.

    Side Effects

    Abdominal distension
    Hypersensitivity reactions
    Anaphylactic reaction


    It is strongly recommended that the UK National Poisons Information Service be consulted on cases of suspected or actual overdose where there is doubt over the degree of risk or about appropriate management.

    The following number will direct the caller to the relevant local centre (0844) 892 0111

    Information may be obtained if you have access to ToxBase the primary clinical toxicology database of the National Poisons Information Service. This is available via password on the internet ( ) or if this is unavailable at the backup site ( ).

    Shelf Life and Storage

    Store below 30 degrees C.

    Store in the original container.

    Further Information

    Last Full Review Date: June 2012

    Reference Sources

    Drugs During Pregnancy and Lactation: Treatment Options and Risk Assessment, 2nd edition (2007) ed. Schaefer, C., Peters, P. and Miller, R. Elsevier, London.

    Martindale: The Complete Drug Reference, 37th edition (2011) ed. Sweetman, S. Pharmaceutical Press, London.

    Summary of Product Characteristics: Fybogel Mebeverine. Forum Health Products Ltd. Revised July 2017.

    NICE Evidence Services Available at: Last accessed: 21 June 2012

    The Drug Database for Acute Porphyria. Available at (accessed June 2012)

    The Renal Drug Handbook. 3rd edition. (2009) ed. Ashley, C and Currie, Radcliffe Publishing Ltd, Abingdon.

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