I'm afraid I can't comment much from this distance. Like most dermatologists, I have many patients with chronic itch. Controlling this is hard--cortisone creams, topical anesthetic lotions, oral antihistamines--all of these are used (I'm sure you've tried some as well.) You doctor will need to keep trying different methods. However, you may well not be able to abolish the problem altogether, just control it. If necessary, seeing another doctor just to get a fresh perspective may be of use. But there's usually not a magic bullet for this kind of thing.
By the way, I don't know what a "pin stroke" is. If you mean a neurological stroke, you might ask your neurologist whether the kind of itch you have is common afterward, and whether special neurological medications might be of use.
Best.
Dr. Rockoff