Pat,   I have researched ccvsi over the past year, but learned that the improvements were few and far between for patients with PPMS. The affected veins in PPMS patients are too deep and dangerous to remedy. The Nuvigil is my wonder drug in that it gives me energy and a positive attitude. It was prescribed to me over 10 years ago by my neurologist. Nuvigil is an updated version of Provigil. It is made by Cephalon. Without Nuvigil my life would be without any momentum. I highly reccommend it to anyone with lethargy associated with MS. Contact your neurologist in order to get a prescription. It is very expensive, Cephalon has a financial aid program for those who qualify. Hope this helps. Marie