Your brother will have to consult with his Physician if he wants to take Levodopa and Amantodine. His Physician will, first, have to determine if Levodopa and Amantodine is right for him.
Not all drugs are tollerated by everyone that takes them. So, his Doctor will have to determine if the two drugs will be safe for him to use.
For example, A small number of suicidal attempts, some of which have been fatal, have been reported in patients treated with amantadine. And therefore, Physicians have to besure that the potential risks outweigh the benefit of treatment before you can buy.
Hope this answers your question!
REFERENCE(S)
1. Giselle Goetz with Judith A. Myers-Walls, PhD, CFLE, 2006.
PPP: Child Growth & Development || Talking With Parents About Normal Age-Related Fears || Some fears are normal
2. MentalHealth.com, 2006.
Amantadine - Parkinson's disease medication information and resources