Australian Approved Name (AAN): Magnesium hydroxide
Organic/Inorganic: Inorganic
Molecular formula: Mg(OH)2
Molecular weight: 58.32
Conversions (% magnesium): 41.68
RDI for Magnesium as per NHMRC:
Infants – 0-6 months – 30mg/day (AI)
Infants – 7-12 months – 75mg/day (AI)
Children – 1-3 years – 80mg/day
Children – 4-8 years – 130mg/day
Boys – 9-13 years – 240mg/day
Boys – 14-18 years – 410mg/day
Girls – 9-13 years – 240mg/day
Girls – 14-18 years – 360mg/day
Men – 19-30 years – 400mg/day
Men – 31->70 years – 420mg/day
Women – 19-30 years – 310mg/day
Women – 31->70 years – 320mg/day
Pregnancy – 14-18 years – 400mg/day
Pregnancy – 19-30 years – 350mg/day
Pregnancy – 31-50 years – 360mg/day
Lactation – 14-18 years – 360mg/day
Lactation – 19-30 years – 310mg/day
Lactation – 31-50 years – 320mg/day
Mandatory components: Magnesium
Warnings and Restrictions: When used as an active ingredient, can only be supplied as an uncompounded medicine substance packed for retail sale, and must comply with an uncompounded substance monograph of the British Pharmacopoeia, as in force or existing from time to time.
The requirements specified in paragraph (a) below apply to a medicine that contains the ingredient when:
– the following warning statement is not specified on the label:
LAX6 – Contains magnesium, which may have a laxative effect or cause diarrhoea (or words to that effect).
(a) When the medicine is not promoted or marketed as laxative, contains more than 2g magnesium hydroxide per maximum recommended daily dose, the following warning statements are required on the label:
LAX5 – This product contains [name of the herb(s) or the chemical component(s)].
LAX4 – This product may have laxative effect.
The requirements specified in paragraphs (b) to (d) below apply to a medicine that contains the ingredient:
(b) Magnesium is a mandatory component of magnesium hydroxide.
(c) When used in a medicine:
(i) with an oral route of administration;
(ii) not indicated for laxative (or related) use; and
(iii) where the maximum recommended daily dose for:
(A) children aged between 1 and 3 years (inclusive) provides 65 mg or more total magnesium from inorganic magnesium salts;
(B) children aged between 4 and 8 years (inclusive) provides 110 mg or more total magnesium from inorganic magnesium salts; or
(C) individuals aged 9 years or older provides 350 mg or more total magnesium from inorganic magnesium salts;
the following warning statement is required on the medicine label:
LAX6 – Contains magnesium, which may have a laxative effect or cause diarrhoea (or words to that effect).
(d) When the route of administration is oral, the medicine must not be directed for use in infants younger than 12 months of age.
Allowable purpose of the ingredient: Active. Excipient
TGA reference: British Pharmacopoeia