Not sure that there is a dosage.One has to get rid of the lack of magnesium in our diet. Can be oral or transdermal. The former can result in bowel problems if high doses whereas transdermal spray bypasses bowel and stomach.

Transdermal can do in weeks what oral dose in many months.

Have used oral for many years and now spray on and find spray better.

Just make a start and the body will absorb what it needs. Take to much orally and the worst that can happen is loose bowels of short duration.

Plenty of info re oral and spray on internet Your health will inproved markedly