How Can My Brother Needs It, Be Prescribed Desoxyn? My

How can my brother needs it, be prescribed Desoxyn? My brother did meth for over 25 years and needs something legal to help him or I feel it would be fatally dangerous to his health if he goes off it completely, (meth that is). He wants to now take a legal drug that would have the same energizing effects. In these later years, he has used it for energy to do chores-only, etc...