Can you take too much accidentally took magnesium?

Step one, count it, because an accidental dose is a number before it is a worry

I accidentally took too much magnesium is a sentence that needs a number attached before it can be answered, and step one of the triage is to count it: the number of capsules or tablets taken multiplied by the elemental magnesium per capsule, read from the label's nutrient line rather than from the compound weight on the front, the label guide's elemental rule mattering most at exactly this moment. A double dose, four capsules of a 150mg-elemental product instead of two, is 600mg, over the 400mg guidance level and likely to loosen stools, and nothing more. A handful, ten capsules, is 1500mg of elemental magnesium, well over the level, and in a healthy adult a diarrhoea day rather than a hospital day, the gut rejecting most of it as osmotic loose stools within hours and the kidneys excreting the absorbed fraction within a day or two, the overflow-valves page's picture, with nausea and cramping likely and hypermagnesaemia unlikely because normal kidneys clear it faster than the gut absorbs it. A whole bottle, sixty or ninety capsules, is nine to fourteen grams of elemental magnesium, a very large ingestion that produces severe diarrhoea and can, even in working kidneys, push blood magnesium up because the sheer amount absorbed outruns excretion for a while, the poisons-centre threshold at which a healthy adult is observed rather than reassured. The compound weight confuses the count, a reader who took ten capsules labelled 500mg of magnesium glycinate having taken about 1000mg elemental and not 5000, so the count uses the elemental figure and, if the label gives only the compound, multiplies by about 0.2 for bisglycinate, 0.16 for citrate and 0.6 for oxide.

Step two, who you are, step three, what to do, and the one case that is always an emergency

Step two is who you are, because the same number means different things. A healthy adult with working kidneys, on no interacting medicines: the count above applies, a double or a handful being a gut day and a bottle being a call. Someone with kidney disease, reduced kidney function or on dialysis: any accidental excess is a medical question from the first capsule, because impaired excretion lets magnesium accumulate from doses a healthy adult clears, and hypermagnesaemia's lethargy, weakness, low blood pressure and slowed heart become possible at amounts that would only loosen a healthy adult's stools, so the action is a call to a doctor or the emergency service straight away. A child who has swallowed adult magnesium, from a bottle left open or Epsom salts in a bathroom: always an emergency assessment, a call to the poisons service or emergency care immediately with the product and the count, this site giving no supplement guidance to minors and giving this one safety instruction without hesitation. Step three, what to do, for the healthy adult: stop every magnesium source for a day or two, including antacids and laxatives; drink to thirst and a little more as the stools come, with a salty meal for the sodium; eat normally; do not induce vomiting; expect loose stools within hours and nothing much after a day; and seek urgent help if any systemic sign appears, unusual drowsiness, muscle weakness, flushing, dizziness with a slow pulse, confusion or breathlessness, saying what was taken. The triage filed: count the elemental dose, ask who you are, act accordingly, with a child's ingestion always an emergency, and the worked example printing 150mg elemental per capsule so that the count takes a second, £19.99 for 90 days at 22p, and a lid that goes back on.

The verdict, a number, a person, and an action

Can you take too much magnesium accidentally: yes, and the triage is three steps, count the elemental dose so that a double is 600mg and a handful about 1500mg, both a diarrhoea day in a healthy adult while a whole bottle is a call for observation, ask who you are since kidney disease turns any excess into a medical question and a child's ingestion is always an emergency, and act by stopping every source, drinking, eating and expecting loose stools, with urgent help for any systemic sign. The capsule that makes the count easy: Futuro Labs Magnesium Glycinate, 150mg elemental per capsule printed on the label, £19.99 for 90 days at 22p a day, and the lid back on.

What to check on the label

Questions people also ask

I accidentally took a double dose of magnesium, what will happen?

In a healthy adult, probably loose stools within hours and nothing more: a double dose of a 150mg-elemental capsule is 600mg, over the 400mg guidance level, and the gut and the kidneys clear the surplus within a day or two.

I took a handful of magnesium capsules, do I need to go to hospital?

Not with working kidneys and no systemic signs: around 1500mg of elemental magnesium is a diarrhoea day, managed by stopping sources, drinking and eating; a whole bottle, nine grams or more, is a call to the poisons service or emergency line for advice and observation.

What if someone with kidney disease takes too much magnesium?

Call a doctor or the emergency service straight away: impaired excretion lets magnesium accumulate from doses a healthy adult clears, and the lethargy, weakness, low blood pressure and slowed heart of hypermagnesaemia become possible at amounts that would only loosen a healthy adult's stools.

What if a child swallows magnesium tablets?

Always an emergency assessment: call the poisons service or emergency care immediately with the product and the number taken, whatever the amount, and keep supplements and Epsom salts out of a child's reach.

Should I make myself sick after taking too much magnesium?

No: do not induce vomiting; stop every magnesium source, drink to thirst and a little more, eat a salty meal, expect loose stools, and seek urgent help if drowsiness, weakness, flushing, a slow pulse, confusion or breathlessness appears.

Sources

1. The poisons-centre literature on magnesium ingestion: acute oral magnesium overdose in people with normal kidney function produces gastrointestinal effects and is managed with fluids and observation, with hypermagnesaemia and hospital treatment reserved for impaired excretion or very large ingestions, and any ingestion by a child assessed by a poisons service. PubMed record
2. The hypermagnesaemia literature: raised serum magnesium is rare with normal kidney function and occurs with impaired excretion or massive intake from magnesium laxatives and antacids, presenting with nausea, lethargy, low blood pressure, muscle weakness and slowed heart conduction, and treated in hospital with intravenous calcium and, where needed, dialysis. PubMed record
3. The hypermagnesaemia literature: the kidneys excrete surplus magnesium, so supplementation is safe for healthy adults within guidance and warrants medical advice in chronic kidney disease, where impaired excretion allows magnesium to accumulate. PubMed record
4. Expert Group on Vitamins and Minerals. Safe Upper Levels for Vitamins and Minerals. Food Standards Agency, 2003 (magnesium guidance level 400mg a day from supplements). https://cot.food.gov.uk/sites/default/files/vitmin2003.pdf

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