Low magnesium is a decrease in the amount of magnesium in the blood, which can cause symptoms like nausea, vomiting, loss of appetite, weakness, muscle cramps, or a rapid heartbeat.

Magnesium is an essential mineral that supports nerve and muscle function, regulates blood sugar, and strengthens bones. It is mainly found in foods such as seeds, peanuts, and milk.

Treatment for low magnesium, also known as hypomagnesemia, is usually guided by a primary care doctor or nutrition specialist. It may involve eating more magnesium-rich foods, taking supplements, or receiving magnesium sulfate injections in more serious cases.

Symptoms of low magnesium

The most common symptoms of low magnesium include:

Nausea and vomiting
Loss of appetite
Weakness or extreme fatigue
Tremors, muscle spasms, or cramps
Dizziness
Rapid or irregular heartbeat

Severe magnesium deficiency can also cause depression, agitation, delirium, psychosis, or even coma.

Low magnesium is often linked to reduced potassium and calcium levels in the blood, which can lead to generalized seizures or supraventricular tachycardia.

How to confirm the diagnosis

A doctor can diagnose low magnesium by assessing symptoms, reviewing medical history, and performing physical and laboratory exams.

Blood tests are typically ordered to check magnesium, calcium, and potassium levels, as well as a metabolic panel. Heart tests, such as an electrocardiogram, may also be recommended.

Magnesium reference values

In adults, normal magnesium levels range from 1.6 mg/dL to 2.6 mg/dL.

Low magnesium is confirmed when blood levels fall below 1.6 mg/dL.

It’s important to note that reference values may vary depending on the laboratory and testing method used.

Possible causes

The main causes of low magnesium include:

Diet low in magnesium
Chronic diarrhea, excessive laxative use, or inflammatory bowel disease
Malnutrition or anorexia nervosa
Bariatric surgery
Frequent and excessive alcohol consumption
Gitelman syndrome
Use of certain medications, such as diuretics, antiulcer drugs, antifungals, immunosuppressants, or chemotherapy agents

During pregnancy, especially in the first trimester, magnesium is excreted in greater amounts through the kidneys, which may make supplementation necessary.

Treatment for low magnesium

Treatment for low magnesium should always be directed by a doctor, with the goal of restoring healthy magnesium levels in the blood.

The main treatment options are:

1. Magnesium-rich diet

In mild cases, treatment may involve eating more foods high in magnesium, such as almonds, oats, bananas, and spinach.

2. Magnesium supplements

When dietary changes are not enough, oral magnesium supplements may be prescribed.

These supplements can sometimes cause side effects such as diarrhea and abdominal cramps, making them difficult to tolerate for some people.

In more severe cases of low magnesium, hospitalization may be needed for intravenous magnesium administration.

Possible complications

Low magnesium can increase the risk of several health conditions, including:

Type 2 diabetes
Heart attack
Heart failure
Angina
High blood pressure
Kidney stones
Premenstrual syndrome
Mental health disorder

Low Magnesium: Symptoms, Causes & Treatment