There is no special "medicinal" cannabis, that is just something made up by seedbanks looking to hype their wares. All Cannabis is medicinal. When it comes to which strains to use, its all down to the individual patient and their disease. What helps me, may not help you and vice-versa

In the end, those of us using medicinally just have to "suck it and see" which strains work for us.
Hope this helps you to avoid being sold super-expensive over hyped dutch "Medi-weed".