This information is intended for use by health professionals
Maalox 175mg/200mg Oral Suspension
Each 5 ml of oral solution contains:
Aluminium hydroxide 175mg
Magnesium hydroxide 200mg
Excipients with known effect:
This medicinal product contains 0.0068 mmol (0.157 mg) of sodium and 50 mg of sorbitol per 5 ml dose.
For the full list of excipients, see section 6.1.
White oral suspension, homogenous after shaking
Antacid therapy in gastric and duodenal ulcer, gastritis, heartburn and gastric hyperacidity.
Adults (including the elderly):
10 – 20 ml taken 20 minutes to one hour after meals and at bedtime or as required. Maalox can be taken with water or milk if required.
Not recommended for children under 14 years.
Method of administration
For oral administration.
Shake before use.
Maalox should not be used in patients who are severely debilitated or suffering from renal insufficiency, or if there is severe abdominal pain and/or the possibility of bowel obstruction.
Hypersensitivity to the active substances or to any of the excipients listed in section 6.1.
Aluminium hydroxide may cause constipation and magnesium salts overdose may cause hypomotility of the bowel; large doses of this product may trigger or aggravate intestinal obstruction and ileus in patients at higher risk such as those with renal impairment, or the elderly.
Aluminium hydroxide is not well absorbed from the gastrointestinal tract, and systemic effects are therefore rare in patients with normal renal function. However, excessive doses or long-term use, or even normal doses in patients with low-phosphorus diets may lead to phosphate depletion (due to aluminium-phosphate binding) accompanied by increased bone resorption and hypercalciuria with the risk of osteomalacia. Medical advice is recommended in case of long-term use or in patients at risk of phosphate depletion.
In patients with renal impairment, plasma levels of both aluminium and magnesium increase. In these patients, a long-term exposure to high doses of aluminium and magnesium salts may lead to dementia, microcytic anemia.
Aluminium hydroxide may be unsafe in patients with porphyria undergoing hemodialysis.
This product contains sorbitol (E420). Patients with rare hereditary problems of fructose intolerance should not take this medicine.
This medicinal product contains less than 1 mmol sodium (23mg) per dose, i.e. essentially “sodium free”.
Antacids are known to interfere with the absorption of drugs such as tetracyclines, vitamins, ciprofloxacin, ketoconazole, levothyroxine, hydroxychloroquine, chloroquine, chlorpromazine, rifampicin, cefdinir, cefpodoxime, rosuvastatin.
Caution is advised when used concomitantly with polystyrene sulphonate due to the potential risks of reduced effectiveness of the resin in binding potassium, of metabolic alkalosis in patients with renal failure (reported with aluminium hydroxide and magnesium hydroxide), and of intestinal obstruction (reported with aluminium hydroxide).
Aluminium hydroxide and citrates may result in increased aluminium levels, especially in patients with renal impairment.
Urine alkalinisation secondary to administration of magnesium hydroxide may modify excretion of some drugs; thus, increased excretion of salicylates has been seen.
There are no or limited amount of data from the use of aluminium hydroxide and magnesium hydroxide in pregnant women. Animal studies are insufficient with respect to reproductive toxicity (see section 5.3). Maalox is not recommended during the first trimester of pregnancy and in women of childbearing potential not using contraception. Caution should be exercised when prescribing to pregnant and lactating women.
Because of the limited maternal absorption, when used as recommended, aluminium hydroxide and magnesium salt combinations are considered compatible with lactation.
No effects on the breastfed newborns/infant are anticipated since the systemic exposure of the breast-feeding woman to aluminium hydroxide and magnesium hydroxide is negligible.
No fertility data is available.
The following CIOMS frequency rating is used, when applicable:
Very common (≥1/10), common (≥1/100 to <1/10), uncommon (≥1/1,000 to <1/100), rare (≥1/10,000 to <1/1,000), very rare (<1/10,000), not known (cannot be estimated from available data)
Immune system disorders
Not known: hypersensitivity reactions, such as pruritus, urticaria, angioedema and anaphylactic reactions
Gastrointestinal side effects are uncommon.
Uncommon: diarrhoea or constipation (see section 4.4)
Frequency not known: Abdominal pain
Metabolism and nutrition disorders
Very rare: Hypermagnesemia, including observations after prolonged administration of magnesium hydroxide to patients with renal impairment
Frequency not known:
Hypophosphatemia, in prolonged use or at high doses or even normal doses of the product in patients with low-phosphorus diets, which may result in increased bone resorption, hypercalciuria, osteomalacia (see section 4.4).
Reporting of suspected adverse reactions
Reporting suspected adverse reactions after authorisation of the medicinal product is important. It allows continued monitoring of the benefit/risk balance of the medicinal product. Healthcare professionals are asked to report any suspected adverse reactions via Yellow Card Scheme at: www.mhra.gov.uk/yellowcard or search for MHRA Yellow Card in the Google Play or Apple App Store.
Serious symptoms are unlikely following overdose. Discontinue medication and correct fluid deficiency if necessary.
Reported symptoms of acute overdose with aluminium hydroxide and magnesium salts combination include diarrhoea, abdominal pain, vomiting.
Large doses of this product may trigger or aggravate intestinal obstruction and ileus in patients at risk (see section 4.4).
Aluminium and magnesium are eliminated through urinary route; treatment of acute overdose consists of administration of IV Calcium Gluconate, rehydration and forced diuresis. In case of renal function deficiency, haemodialysis or peritoneal dialysis is necessary.
Pharmacotherapeutic group: Antacids; aluminium compound combinationsATC code: A02AB10
Maalox is a balanced mixture of two antacids; aluminium hydroxide is a slow-acting antacid and magnesium hydroxide is a quick-acting one. The two are frequently combined in antacid mixtures. Aluminium hydroxide on its own is an astringent and may cause constipation. This effect is balanced by the effect of magnesium hydroxide, which, in common with other magnesium salts, may cause diarrhoea. Gastro-intestinal side effects are thus rare with Maalox and this makes it especially suitable when long term therapy is necessary.
The absorption of aluminium and magnesium from antacids is small. Aluminium hydroxide is slowly converted to aluminium chloride in the stomach. Some absorption of soluble aluminium salts occurs in the gastro-intestinal tract with urinary excretion. Any absorbed magnesium is likewise excreted in the urine. Aluminium containing antacids should not be administered to patients with renal impairment where increased plasma concentration may occur.
Non-clinical data are limited and are considered insufficient with respect to repeated dose toxicity, genotoxicity and toxicity to reproduction and development.
Hydrochloric acid (10%)
Citric acid (monohydrate)
Sorbitol liquid 70% (not crystallising) (E420)
Hydrogen peroxide solution 30%
After first opening: 6 months
Do not store above 25°C.
Polyethylene terephthalate (PET) bottle with polypropylene (PP) closure and polyethylene (PE/LDPE) liner: 250ml
No special requirements.
Opella Healthcare UK Limited, trading as Sanofi
410 Thames Valley Park Drive,
27 January 2017
01 November 2021