What Are The Repercussions Of Taking Extra Dosage Of Magnesium Supplements?

Posted on Sun, 18 Dec 2016

Medically reviewed by Ask A Doctor - 24x7 Medical Review Team

Sun, 18 Dec 2016 Answered on

Mon, 9 Jan 2017 Last reviewed on

Question : Hi, I'm a hard worker, and used to wake with muscle cramps so about a year ago started taking magnesium which helped. last night I took my normal two mega magnzium before I when to bed, but then I couldn't sleep so I got up and wrapped Christmas presents, I then out of habit took a further two magnesium and when to bed!! I then woke up two hours later with a racing heart and what felt like heart palpitations? I was very frightened for a while then after sitting up for an hour finally went to sleep! I've not woken and still feel like my heart is racing? Have I dine permanent damage?

Answered by Dr. Ilir Sharka (13 minutes later)

Brief Answer:
I would explain as follows:

Detailed Answer:
Hello!

Welcome and thank you for asking on HCM!

Regarding your concern, I would explain that your symptoms seem to be related to a high dose of magnesium.

You should know that magnesium like potassium is essential for a normal activity of the muscles, including the myocardial muscle.

When there is deficiency, the muscles and heart do not work properly.

The same may occur when it is taken in high doses, especially when considering the fact that it may cause troubles in the excitability of the myocardial muscle.

From the other hand chronic intake of magnesium supplements can also lead to hyperkalemia.

So, if the problem persists I would recommend consulting with your attending physician for a physical exam and some tests:

- a resting ECG
- blood electrolytes (potassium, sodium, calcium, magnesium)
- complete blood count for anemia
- uric acid levels (increased uric acid levels can lead to muscle cramps).

Hope you will find this answer helpful!

Kind regards,

Dr. Iliri

Above answer was peer-reviewed by : Dr. Chakravarthy Mazumdar