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Sodium alginate with potassium bicarbonate oral formulations

Updated 2 Feb 2023 | Alginate preparations


Oral formulations containing sodium alginate with potassium bicarbonate.

Drugs List

  • ACIDEX ADVANCE ANISEED oral suspension
  • GAVISCON ADVANCE ANISEED oral suspension sugar-free
  • GAVISCON ADVANCE MINT chewable tablet
  • GAVISCON ADVANCE PEPPERMINT oral suspension sugar-free
  • sodium alginate 1g/10ml and potassium bicarbonate 200mg/10ml oral suspension sugar-free
  • sodium alginate 500mg and potassium bicarbonate 100mg chewable tablets sugar-free
  • Therapeutic Indications


    Gastric reflux
    Gastro-oesophageal reflux disease
    Heartburn of pregnancy
    Laryngopharyngeal reflux



    5ml to 10 ml or one to two tablets after meals and at bedtime.


    The manufacturers recommend that children aged under 12 years of age should only be treated on medical advice.

    Alternative sources suggest the following doses:

    Children aged 6 to 12 years: 1 tablet after meals and at bedtime.

    Children aged 2 to 12 years: 2.5ml to 5 ml after meals and at bedtime.


    5ml to 10 ml or one to two tablets after meals and at bedtime.


    None known

    Precautions and Warnings

    Children under 12 years
    Restricted potassium intake
    Restricted sodium intake
    Congestive cardiac failure
    History of nephrolithiasis
    Renal impairment

    Contains more than 1 mmol (23 mg) sodium per dose
    Contains potassium 78mg (2.0mmol) per 10ml or 2 tablet dose
    Some formulations contain aspartame - caution in phenylketonuria
    Not all presentations are licensed for all indications
    Some formulations contain hydroxybenzoate
    Advise patient not to take other medicines within 2 hours
    Advise patient to see doctor if symptoms persist for 7 days with treatment

    Use with caution in patients with hypercalcaemia, nephrocalcinosis and history of renal calculi as each dose (10ml or 2 tablets) contains 200mg (2mmol) calcium.

    Restricted sodium intake - Contains sodium 106mg (4.6mmol) per 10ml dose or 103mg (4.5mmol) in two tablets.

    Pregnancy and Lactation


    The preparation is considered safe for use in pregnancy.

    There is consensus that antacids may be used during all phases of pregnancy and have been widely prescribed without evidence of adverse effects at normal therapeutic use (Schaefer, Peters and Miller, 2015 and Lee, A et al 2000).

    It should be noted that the preparation is licensed for indigestion during pregnancy. From clinical data no adverse effects have been seen on the course of pregnancy or on the health of the foetus/new-born child.

    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 to 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 ( ).


    The preparation is considered safe for use in breastfeeding.

    UK licensed product information advises that the preparation may be used during breastfeeding.

    Alginic acid is not absorbed orally (LactMed via ToxNet).

    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

    Side Effects

    Anaphylactoid 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 ( ).

    Further Information

    Last Full Review Date: November 2016

    Reference Sources

    Drugs During Pregnancy and Lactation: Treatment Options and Risk Assessment, 3rd edition (2015) ed. Schaefer, C., Peters, P. and Miller, R. Elsevier, London.

    Summary of Product Characteristics: Gaviscon Advance Mint Chewable tablets. Forum Health Ltd. Revised September 2014.

    Summary of Product Characteristics: Gaviscon Advance - Peppermint. Forum Health Ltd. Revised September 2014.

    Summary of Product Characteristics: Gaviscon Advance - Aniseed. Forum Health Ltd. Revised September 2014.

    Therapeutics in Pregnancy and Lactation (2000) Lee, A., Inch, S. and Finnigan, D. Radcliffe Medical Press, Abingdon.

    NICE Evidence Services Available at: Last accessed: 24 August 2017

    US National Library of Medicine. Toxicology Data Network. Drugs and Lactation Database (LactMed).
    Available at:
    Antacids, Oral Last revised: 7 September 2013
    Last accessed: 17 November 2016

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