It is a remedy for muscles, spasms, cramps and pain. It contributes to the treatment of muscle pain, for example, menstrual pain, common tension in the cervical or shoulder area and painful spasms in the gastrointestinal tract. Magnesium Phosphoricum Dosage: Let the tablets dissolve slowly in the mouth, separated from eating, approximately 30 minutes before or after. The usual dose is 2 – 4 tablets daily, unless otherwise stated.