What Are the Symptoms of Low Magnesium, and How Do You Treat It?

Written by Joanna Jan, MD | Reviewed by Katie E. Golden, MD
Reviewed on May 6, 2026

Key takeaways:

• Magnesium is a mineral that helps your body work properly. But your body can’t make magnesium on its own, so it’s important to get enough of it from your diet.
• A low magnesium level, also called “hypomagnesemia,” has several different causes, including low dietary intake, medications, or poor absorption in the digestive tract.
• Severe magnesium deficiency can affect your nervous system and heart. It can lead to things like muscle spasms, seizures, or heart arrhythmias. 
• Low magnesium is treated with oral or intravenous magnesium supplements. 

Magnesium is a mineral that the body uses for many processes. You’ve probably heard more about other electrolytes — like sodium, potassium, and calcium. But like these other electrolytes, magnesium plays a critical role in your nervous system, heart health, and metabolism. 

Low magnesium levels, also called “hypomagnesemia,” can cause a variety of problems. Some are more serious than others. Here, we’ll discuss the symptoms, causes, and diagnosis of this condition, along with treatment options.

Symptoms of magnesium deficiency

Magnesium deficiency can cause a range of symptoms in different parts of the body. Many symptoms are linked to magnesium’s role in controlling electrical signals in the nerves and heart.

Some of the symptoms of magnesium deficiency include:

• Weakness and fatigue
• Tremors or muscle twitching
• Muscle cramping 
• Heart palpitations or heart arrhythmias
• Numbness
• Seizures 
• Confusion or mood changes 

Magnesium deficiency often occurs alongside low levels of other important electrolytes, especially calcium and potassium. That’s partly because they share many of the same underlying causes. 

Causes of magnesium deficiency

There are several causes of low magnesium levels. 

Low magnesium intake

This can happen if you’re malnourished or don’t eat enough foods that have magnesium. The good news is that there are a lot of foods that are rich in magnesium (more on this below).

Gastrointestinal conditions

Intestinal conditions can affect how magnesium is absorbed in the gut. This can happen even if you get enough magnesium in your diet. Examples of these conditions include:

• Celiac disease
• Inflammatory bowel disease 
• Gastric bypass surgery 

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You can also lose magnesium through your digestive tract when you vomit or have diarrhea for any reason. 

Kidney conditions 

Health conditions can affect how your kidneys process magnesium. The result is that your kidneys pass extra magnesium through urine. And this can cause a magnesium deficiency.

These conditions include kidney diseases, as well as others that affect the kidneys, such as:

• High blood sugar from diabetes 
• High calcium levels 
• Thyroid disease
• Bartter syndrome and Gitelman syndrome, two inherited conditions

Article source: GoodRx.com