Newbie - I just got off the phone with Medicare part b regarding the 3% solution. At the moment according to a site I am not allowed to list (google drug shortages) there are shortages of the 7 and 3 % etc solutions. I have not found a single pharmacy near me who have it or can get it (the 3% 4 ml size). I was able to find a supplier but it would be extremely costly to buy every month and so I asked medicare part b if they could retroactively cover it and they said no. You have to buy from a company that accepts Medicare. The site I listed above will show suppliers that may have what you need but they are unlikely to take medicare. This is a big problem.