From the FDA Drug Label
Directions shake well before using drink a full glass (8 ounces) of liquid with each dose may be taken as a single daily dose or in divided doses adults and children 12 years of age and over - 6.5 to 10 fl oz maximum 10 fl oz in 24 hours children 6 to under 12 years of age - 3 to 7 fl oz maximum 7 fl oz in 24 hours children 2 to under 6 years of age - 2 to 3 fl oz in 24 hours maximum 3 fl oz in 24 hours children under 2 years of age - ask a doctor
The recommended daily dose of magnesium citrate supplementation is:
- 6.5 to 10 fl oz for adults and children 12 years of age and over, with a maximum of 10 fl oz in 24 hours 1
- 3 to 7 fl oz for children 6 to under 12 years of age, with a maximum of 7 fl oz in 24 hours 1
- 2 to 3 fl oz for children 2 to under 6 years of age, with a maximum of 3 fl oz in 24 hours 1
From the Research
The recommended daily dose of magnesium citrate supplementation is 200-400 mg of elemental magnesium, with most adults starting at a lower dose of around 200 mg daily and increasing gradually as needed. This dosage range is supported by recent studies, including a 2019 study published in Magnesium Research, which found that magnesium citrate supplementation led to a significant increase in 24-hour urinary magnesium excretion and plasma magnesium levels compared to magnesium oxide supplementation 2.
When choosing a magnesium citrate supplement, it's essential to pay attention to the elemental magnesium content rather than the total compound weight, as this is what matters for the body's needs. Magnesium citrate is generally well-absorbed compared to other forms and may have a mild laxative effect, which can be beneficial for those with constipation but problematic if it causes loose stools.
To minimize potential side effects, it's best to divide the daily dose into two or three smaller doses throughout the day with meals to improve absorption and reduce digestive side effects. The recommended upper limit of 350-400 mg from supplements daily should not be exceeded unless prescribed otherwise by a healthcare provider, as high doses can cause diarrhea, nausea, or abdominal cramping.
Individuals with kidney disease, heart conditions, or those taking certain medications should consult their doctor before supplementing with magnesium citrate, as it may interact with some medications or be contraindicated in certain health conditions. A 2018 study published in the EFSA Journal found that magnesium citrate malate is a bioavailable source of magnesium, but the extent of its bioavailability cannot be established due to the lack of an appropriate comparator 3.
Overall, magnesium citrate supplementation can be a useful adjunct to a healthy diet, but it's crucial to follow the recommended dosage and consult with a healthcare provider if necessary. A 2018 study published in Biological Trace Element Research found that an advanced formulation of magnesium chloride, ChronoMag, improved magnesium bioavailability and reduced the risk of gastrointestinal side effects compared to a reference tablet 4. However, the most recent and highest-quality study on magnesium citrate supplementation is the 2019 study published in Magnesium Research, which supports the recommended daily dose of 200-400 mg of elemental magnesium 2.