A friend of mine, age 55, who is otherwise fully healthy, has an issue of serious heart palpitations.
He used to have an episode once a week on average, but lately it sometimes happens that he is having one 3 to 4 times a day, lasting around 10 to 15 minutes.
He has been turned inside out by cardiologists, but they cannot find any cause, let alone a cure.

Is there any supplement my friend can take that will not harm him, but probably will control this problem?

Thank you in advance for your advice.

Not sure exactly what "palpitations" means, but I'd start here:
http://www.afibbers.org/atrial_fibrillation.htm

Magnesium is a major basic factor:
http://www.yourhealthbase.com/database/ ... esium.html
Lots of other stuff and lots of links, some at bottom of pages.

FRM

gofanu, thank you for the links.
However, I am afraid that if I pass on these links to my friend he will get confused and will just sit tight without doing anything. So, he'll continue to have his daily heart rythm problems.
If I were to advise him to take two supplements, that won't harm and probably help, what would those two supplements be?

From what I read I would say at least Magnesium (what dosage?) en what should be the other?

A good start would be a combo Like, "Magnesium Potassium Aspartate."
Mag 100mg. Pot 99mg
probably twice a day would be a good starting dose.
You don't want to go over 400mg MAG. in a single dose because it'll start acting like a laxitive.
I'm suprised his cardio doc hasn't started him on blood thinners yet??
People who have A-fib generally start throwing blood clots which can cause a stroke or other problems.
So yes he needs to get on this pretty quick!

Johnwen, thank you very much for your clear advice.