MAGNESIUM HYDROXIDE
Brand name Cream of Magnesia,Milk of Magnesia
Used in the following combined preparations Carbellon, Maalox, Mucaine, Mucogel and others
GENERAL INFORMATION
Magnesium hydroxide is a fast-acting antacid given to neutralize stomach acid.
The drug is available in a number of over-the-counter preparations for the treatment of indigestion and heartburn.
Magnesium hydroxide also prevents pain caused by stomach and duodenal ulcers, gastritis, and reflux oesophagitis, although other drugs are normally used for these problems nowadays.
It also acts as a laxative by drawing water into the intestine from the surrounding blood vessels to soften the faeces.
Magnesium hydroxide is not often used alone as an antacid because of its laxative effect.
However, this effect is countered when the drug is used in combination with aluminium hydroxide, which can cause constipation.
INFORMATION FOR USERS
Follow instructions on the label. Call your doctor if symptoms worsen.
How taken
Tablets, liquid, powder.
Frequency and timing of doses
4 x daily with water, preferably an hour after food.
Adult dosage range
Antacid 1 -2g per dose (tablets); 5-20ml per dose (liquid).
Laxative 5-20ml per dose (liquid).
Onset of effect
Antacid within 15 minutes. Laxative 2-8 hours.
Duration of action
2-4 hours.
Diet advice
None.
Storage
Keep in a closed container in a cool, dry place out of the reach of children.
Missed dose
Take as soon as you remember.
Stopping the drug
When used as an antacid, can be safely stopped as soon as you no longer need it. When given as ulcer treatment, follow your doctor’s advice.
Exceeding the dose
An occasional unintentional extra dose is unlikely to be a cause for concern. But if you notice any unusual symptoms, or if a large overdose has been taken, notify your doctor.
POSSIBLE ADVERSE EFFECTS
Diarrhoea is the only common adverse effect of this drug. Dizziness and muscle weakness due to absorption of excess magnesium in
the body may occur in people with poor kidney function.
QUICK REFERENCE
Drug group Antacid and laxative
Overdose danger rating
Low Dependence rating Low
Prescription needed No
Available as generic Yes
SPECIAL PRECAUTIONS
Be sure to consult your doctor or pharmacist before taking this drug if:
You have a long-term kidney problem.
You have a bowel disorder.
You are taking other medications.
Pregnancy
No evidence of risk.
Breast-feeding
No evidence of risk.
Infants and children
Not recommended under 1 year except on the advice of a doctor. Reduced dose necessary for older children.
Over 60
No special problems.
Driving and hazardous work
No known problems.
Alcohol
Avoid excessive alcohol as it irritates the stomach and may reduce the benefits of the drug.
INTERACTIONS
General note Magnesium hydroxide interferes with the absorption of a wide range of drugs taken by mouth, including tetracycline antibiotics, iron supplements, diflunisal, phenytoin, and penicillamine.
Enteric-coated tablets As with other antacids, magnesium hydroxide may allow break-up of the enteric coating of tablets, sometimes leading to stomach irritation.
PROLONGED USE
Magnesium hydroxide should not be used for prolonged periods without consulting your doctor. Prolonged use in people with kidney damage may cause drowsiness, dizziness, and weakness, resulting from accumulation of magnesium in the body.
