In normal quantities, magnesium is one of the essential minerals as it helps us maintain energy and works helps the muscles function. An overdose occurs when the body contains excess magnesium. It can also be referred to as hypermagnesemia or magnesium toxicity. For most healthy individuals, the body will naturally remove any excess magnesium but this cannot occur in the case of kidney disease.

Causes of Magnesium Overdose

Because the body can eliminate extra magnesium that is consumed with food, it is rare to show the effects of overdose. Despite this, some people who have kidney problems may have an overdose as the kidneys will be less efficient when disposing excess quantities therefore causing a buildup.

The other common cause involves taking in extra quantities from another source. One example is consuming higher quantities of supplements than the RDA (recommended daily allowance). Another possibility is consuming large quantities of milk of magnesia (either as a laxative or antacid) and the final option is Epsom salts which are used as tonics or laxatives.

Symptoms of Magnesium Overdose

1. Gastrointestinal Effects

When toxicity does occur, the first symptoms are usually gastrointestinal. Because of magnesium’s effects as a laxative, diarrhea is one of the first symptoms associated with an overdose. Additional symptoms may include vomiting, nausea and upset stomach. Many people who have an overdose will also lose their appetite, causing unintentional weight loss.

2. Cardiovascular Effects

An overdose has also been associated with hypotension (a severe drop in blood pressure). It can also cause heart rhythms to slow down or become erratic (arrhythmias). When high levels accumulate in the bloodstream, it can even cause cardiac arrest.

3. Kidney Damage

Because your kidneys are responsible for removing excess magnesium, large quantities of this nutrient can place a great deal of strain on them. People who already suffer from kidney problems should never take magnesium supplements without doctor’s orders as this can further reduce the ability of the kidneys to filter the magnesium from the blood.

4. Respiratory Depression

Respiratory depression is also known as slow shallow breathing and is one of the possible symptoms of a magnesium overdose. When this occurs your breathing will be ineffective so hypoxia (low blood oxygen) is a possibility. This is extremely dangerous as the body’s cells need oxygen for the vital organs to do their jobs. Symptoms associated with hypoxia include extreme fatigue, shortness of breath, confusion and exercise intolerance.

5. Calcium Deficiency

Calcium and magnesium compete for absorption by the body and because of this consuming excessive amounts of magnesium may cause a calcium deficiency, especially for those with low calcium levels to begin with.

Treatments of Magnesium Overdose

The recommended treatment depends on how severe the toxicity is.

• Mild overdoses may require you to stop consuming over-the-counter magnesium supplements, antacids or laxatives.
• Treatment in emergency situations with very high levels of toxicity may include stomach pumping, renal dialysis, intravenous fluids, injecting calcium chloride or calcium gluconate and artificial breathing support.

No matter the severity, your doctor may want to check for underlying diseases that may have caused the overdose, such as impaired kidney function.

Right Dosage of Magnesium

Category	Recommended Dietary Allowance
Children
1 to 3 years	80 mg a day
4 to 8 years	130 mg a day
9 to 13 years	240 mg a day
Women
14 to 18 years	360 mg a day
19 to 30 years	310 mg a day
31 years and older	320 mg a day
Pregnant	Under 19 years: 400 mg a day 19 – 30 years: 350 mg a day Over 30 years: 360 mg a day
Breastfeeding	Under 19 years: 360 mg a day 19 – 30 years: 310 mg a day Over 30 years: 320 mg a day
Men
14 to 18 years	410 mg a day
19 to 30 years	400 mg a day
31 years and older	420 mg a day

Cautions Before Taking Magnesium

• Allergies. You should always tell your doctor about any allergies you have to medications as well as other allergies including animals, preservatives and food dyes. If you are using an over the counter product, be sure to read the label carefully if you have allergies.
• Pregnancy. During pregnancy it is essential that you ingest the proper quantities of all nutrients as the healthy development of your fetus depends on it. Avoid taking large quantities of supplements, however, as this can be harmful.
• Breastfeeding. While breastfeeding it is essential that you ingest the proper quantities of all nutrients as the healthy development of your baby depends on it. Avoid taking large quantities of supplements, however, as this can be harmful.
• Pediatric Problems. There have been no reported problems with children who consume the recommended amounts of magnesium.
• Geriatric Problems. There have been no reported problems with older adults who consume the recommended amounts of magnesium. However, some research shows that older adults can have lower magnesium levels so a supplement may be recommended.
• Drug Interactions. You should always discuss your other medications with your doctor before taking magnesium supplements as some negative interactions can occur. Some of the most common medications that will require adjustment before taking magnesium include: vismodegib, rilpivirine, quinine, mycophenolic acid, mycophenolate mofetil, licorice, levomethadyl, eltrombopag and digoxin.
• Medical Problems. Magnesium supplements can make heart disease and kidney problems worse so always talk to your doctor before starting the supplement if you have either of these problems.

To avoid magnesium overdose and other discomforts, make sure you follow the precautions above.