Glutathione. Nasal spray

It seems that PD results in or isn't helped by reduced glutathione in the brain. Reading web articles it seems that taking pills isn't an effective way of increasing levels in the brain. Has anyone tried patches, oral or nasal spray, or even suppository alternatives. If so have you noticed any improvement in condition or feeling? 

I have just been reading about a successful trial of glutathione nasal spray, and looking into trying it for my husband, but I have not been able to find a UK source, and the American prices are really high if it’s just going to be a waste of money. Did you manage to track down a UK supplier, and, if so, did you see any improvement? I seem to spend a great deal of time researching alternative solutions to the non-motor symptoms, but haven’t found anything that has proved effective.

I didn’t and as you say to buy from the web is too expensive. I’ve been taking NAC which has mixed reports in whether it increases Glutathione levels but it’s cheaper and can’t hurt.