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Chefaro Ireland Ltd

Chefaro Ireland, 1st Floor, 32 Vauxhall Bridge Road, London, SW1V2SA, UK
Telephone: +44 (0)203 598 9601
E-mail: omegaroi@professionalinformation.co.uk
WWW: www.omegapharma.ie
Medical Information Direct Line: +44 (0)1748 827 299

Summary of Product Characteristics last updated on medicines.ie: 15/09/2014
SPC Milk of Magnesia

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Milk of Magnesia Traditional Mint Flavoured Liquid, 415 mg/5 ml, oral suspension

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Magnesium Hydroxide 415mg per 5ml suspension.

For a full list of excipients, see section 6.1

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Oral suspension.

White, opaque, slightly viscous suspension with an odour of peppermint and a taste of peppermint.

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4.1 Therapeutic indications

Milk of Magnesia is indicated as an antacid for the symptomatic relief of stomach discomfort, indigestion, hyperacidity, heartburn and flatulence.

As a laxative in occasional constipation.

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4.2 Posology and method of administration
Use a 5 ml spoon or the dosing cup provided.

Shake well before use.

Take doses with water if required.

Do not exceed the stated dose.

As an antacid for stomach upsets and indigestion:

Adults (including the elderly) and children aged 12 years and over:

5-10 ml (one or two 5 ml spoonfuls or fill the dosing cup to the first or second line). Repeat as necessary to a maximum daily dose of 60 ml (12, 5ml spoonfuls) in any 24 hours.

Children aged 6-11 years:

5 ml (one spoonful or first line in dosing cup). Repeat as necessary to a maximum daily dose of 30 ml in any 24 hours.

As a laxative:

Adults (including the elderly) and children aged 12 years and older:

30-45 ml at bedtime. Repeat nightly, reducing dose each night until constipation is relieved. Do not use for more than 3 consecutive days.

Children aged 2 - 11 years:

5-10 ml at bedtime. Repeat nightly reducing the dose until constipation is relieved. Do not use for more than 3 consecutive days.

Not to be given to children except on medical advice.

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4.3 Contraindications

Hypersensitivity to any of the ingredients.

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4.4 Special warnings and precautions for use

Keep out of sight and reach of children.

Adequate fluid intake should be maintained during use. If diarrhoea occurs especially in children or the elderly, discontinue use immediately.

If symptoms persist or worsen, consult your doctor.

Prolonged continuous use is not recommended.

In case of renal impairment a doctor should be consulted prior to use as hypermagnesaemia may occur.

Users taking medications either physician or self prescribed should consult a doctor before use.

If a laxative dose is needed every day or if there is a persistent abdominal pain further medical advice should be sought.

Do not use as a laxative for more than three consecutive days, or as an antacid for more than fourteen consecutive days.

Not to be given to children except on medical advice.

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4.5 Interaction with other medicinal products and other forms of interaction

Magnesium hydroxide may interfere locally with the absorption of other drugs taken orally by increasing gastric pH. This can be avoided by giving other drugs 2-3 hours before the administration of magnesium hydroxide on the advice of a doctor.

Milk of Magnesia may interact with digoxin, dicoumerol and cimetidine.

Magnesium hydroxide may increase the absorption of ibuprofen, and decrease the absorption of penicillamine, bisphosphonates, ketaconazole and tetracycline.

The excretion of salicylates will be increased by changes in urinary pH.

Co-administration of sodium polystyrene sulphonate results in a relative excess of bicarbonate ions, which are absorbed, and may lead to metabolic alkalosis.

4.6 Fertility, pregnancy and lactation

For Magnesium hydroxide no clinical data on exposed pregnancies are available.

Animal studies do not indicate direct or indirect harmful effects with respect to pregnancy, embryonal/foetal development, parturition or postnatal development.

Magnesium crosses the placenta and is excreted in small amounts in breast milk. Use during pregnancy and lactation should be avoided unless on the advice of a doctor.

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4.7 Effects on ability to drive and use machines


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4.8 Undesirable effects

The frequency of adverse events is not known and cannot be estimated from the available data.

Diarrhoea may occur which is dose related.

In patients with impaired renal function there may be sufficient accumulation of magnesium to produce toxic effects (see Overdose).

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4.9 Overdose

Symptoms and Signs

Symptoms of overdose include gastrointestinal irritation and watery diarrhoea.

Magnesium poisoning may produce hypermagnesaemia, symptoms of which include nausea, vomiting, flushing, thirst, hypotension, drowsiness, confusion, loss of tendon reflexes, muscle weakness, respiratory depression, cardiac arrhythmias, coma and cardiac arrest.


Treatment consists of the intravenous administration of calcium gluconate injection 10% in a dose of 10-20ml to counteract respiratory depression or heart block. If renal function is normal, adequate fluids should be given to assist removal of magnesium from the body. Dialysis may be necessary in patients with renal impairment or severe hypermagnesaemia.

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5.1 Pharmacodynamic properties

Magnesium hydroxide is practically insoluble in water and solution is not effected until the hydroxide reacts with hydrochloric acid in the stomach to form magnesium chloride. Its neutralising action is almost equal to that of sodium bicarbonate. When the dose is in excess of that required to neutralise the acid the intragastric pH may reach pH 8 or 9. Acid rebound following magnesium hydroxide is clinically insignificant.

Magnesium hydroxide has an indirect cathartic effect resulting from water retention in the intestinal lumen.

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5.2 Pharmacokinetic properties

Magnesium hydroxide exerts its antacid therapeutic effect rapidly within the gastro-intestinal tract following oral administration and this action is therefore independent of pharmacokinetic properties. Following oral administration, about one third to half the magnesium is absorbed very slowly from the small intestine. Magnesium salts are excreted mainly in the urine with small amounts in the faeces and saliva.

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5.3 Preclinical safety data

Magnesium hydroxide has been used for many years and no further data are presented in this section.

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6.1 List of excipient(s)

Sodium hydrogen carbonate

Oil of peppermint


Sodium saccharin


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6.2 Incompatibilities

Not applicable.

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6.3 Shelf life

4 years.

Use within 6 months of opening.

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6.4 Special precautions for storage

Do not store above 25°C. Do not freeze.

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6.5 Nature and contents of container

Blue HDPE bottles with white HDPE screw turn tamper evident inner cap and external click on dosing cap. Pack size 100ml and 200ml.

Not all pack sizes may be marketed.

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6.6 Special precautions for disposal and other handling

Shake bottle well before use.

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Chefaro Ireland Limited

First Floor

Block A

The Crescent Building

Northwood Office Park

Dublin 9


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PA 1186/010/001

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Date of first authorisation: 20 August 1992

Date of last renewal: 20 August 2007

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January 2014

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Active Ingredients

   Magnesium Hydroxide