well, there won't be a point to buy tokens, if you will need to spend 20% from treatment cost for this, right? So, I think, that clients will be offered with several stages of discount. This is how I'd do it.
They do not need to spend 20% more. They get a 20% discount so saving $800 on a $4000 bill is a pretty good incentive to buy the Utility Token. Non Crypto people might not know what a Utility Token but will know what a Pre Paid Credit is and they will be marketed as both depending on where they are marketed.
Gary
As I understand, the drag you are using can be found in any hospital of any country, right? Are you planning to sell rights for using your method to other clinics?