A specialist alopecia areata treatment that creates controlled allergic inflammation on the scalp.
Contact immunotherapy uses chemicals such as diphencyprone to deliberately sensitise the skin, then maintain a mild allergic reaction on bald patches. The aim is to shift immune activity away from the hair follicle and encourage regrowth in alopecia areata. It is usually reserved for more extensive or persistent disease and is performed in specialised centres. Side effects can include itching, blistering, eczema, swollen glands and pigment change, so careful monitoring is needed.
BAD alopecia areata: https://www.bad.org.uk/pils/alopecia-areata