Antacid + antifoaming Pregnancy: §4.6: there are no adequate human data on aluminium hydroxide and magnesium hydroxide in pregnant women and animal studies have not been done; no data suggest harmful effects in pregnancy with simethicone. Caution should therefore be exercised when taken by pregnant women. Some aluminium and magnesium may be secreted in breast milk but the concentration is too small to be harmful; secretion of simethicone in breast milk has not been established but would be most unlikely.

Simeticone with aluminium hydroxide and magnesium hydroxide

Brand names: Asilone, Maalox Plus

This is a compound antacid combining the antifoaming agent simeticone with aluminium hydroxide and magnesium hydroxide, used for symptomatic relief of dyspepsia, heartburn and trapped wind.

Auto-extracted from the source labelling — not yet independently clinician-verified. These values were distilled from the UK SPC (or the US label where noted) but have not had a clinician sign-off. Confirm against the current SmPC before prescribing.

Adult dose

Dose: One or two tablets

Route: Oral - tablets to be sucked or chewed

Frequency: After meals, at bedtime or whenever discomfort is felt

eMC §4.2 (Boots Wind Relief Tablets, UK SPC). Stated dose applies to 'adults and children over 12 years'. ELDERLY: 'There is no need for dosage reduction in the elderly.' PAEDIATRIC (source wording, non-per-kg): children 5 to 12 years - one tablet to be sucked or chewed after meals, at bedtime or whenever discomfort is felt; children under 5 years - not recommended. Verify any under-18 use against a children's formulary. No maximum daily number of tablets and no per-tablet strengths of simeticone, aluminium hydroxide or magnesium hydroxide were stated in the fetched sections - clinician to confirm the product strength from the full SPC. §4.4 advises caution in impaired renal function and that the patient should consult a doctor if symptoms persist for more than 5 days. §4.4 excipient warnings: each tablet contains 571 mg sucrose (as icing sugar - may be harmful to the teeth; unsuitable in rare hereditary fructose intolerance, glucose-galactose malabsorption or sucrase-isomaltase insufficiency) and 402 mg sorbitol (unsuitable in hereditary fructose intolerance; may cause gastrointestinal discomfort and a mild laxative effect).

Dose adjustments

Renal

§4.4: should be used with caution in patients with impaired renal function. No numeric dose adjustment for renal impairment is stated in the fetched sections.

Dose auto-extracted from UK Summary of Product Characteristics (SPC) via the eMC — not yet clinician-verified. Always confirm against the product SmPC and your local formulary before prescribing.

Contraindications

Hypersensitivity to any of the ingredients (§4.3)
Hypophosphataemia (§4.3)

Side effects

Diarrhoea (occasional)
Constipation (occasional)
§4.8 notes the combination of magnesium and aluminium salts minimises these gastrointestinal effects; no other undesirable effects were listed in the fetched section

Interactions

§4.5: may interfere with the absorption of tetracyclines, chloroquine, penicillamine, phenothiazines and quinolone antibacterials when these are given concomitantly

Clinical monograph

How it works

Aluminium and magnesium hydroxides neutralise gastric acid to raise intragastric pH, while simeticone lowers the surface tension of gas bubbles to aid their dispersal; the combined magnesium and aluminium salts balance their opposing effects on bowel habit.

Prescribing in practice

Antacids reduce the absorption of many drugs and should be separated in time from agents such as tetracyclines, quinolones, iron and certain other medicines; aluminium- and magnesium-containing products require caution in renal impairment owing to accumulation.
Magnesium salts tend to cause diarrhoea and aluminium salts constipation, so bowel habit may shift depending on the balance.
It is for short-term symptomatic use; persistent or alarm symptoms warrant investigation.

Monitoring

No routine monitoring is required for short-term use, but review symptom control and exercise caution with repeated use in renal impairment.

Counselling the patient

Take after meals and at bedtime when symptoms occur.
Leave a gap before or after other tablets, as antacids can stop them working properly.
See your prescriber if symptoms persist, worsen or are accompanied by weight loss or difficulty swallowing.

Evidence & guidelines

Compound antacids provide established short-term symptomatic relief of dyspepsia, consistent with NICE dyspepsia guidance.

Reference: NICE CG184; Drug verified in RxNorm (NLM); confirm dosing against the manufacturer SPC (eMC). Verify against your local formulary and current prescribing references before prescribing. The structured dose values shown have been reviewed by a clinician. Monograph status: clinician-reviewed (2026-07-04).

Curated clinical cross-links plus same-class fallbacks.

Calculators

Pathways