Wa alaykum as salaam wa rahmatullahi wa barakaatuhu,
Brother As per my experience, Psoriasis is Sihr... I have treated many people by ruqya and salt bath. Do ruqya and blow on Salt and use a pinch on salt in a bucket of water and do Ghusl. Everyday immerse both the feet in a tub full of hot water and put a tablespoon of common salt (without ruqya) and sit for 15 mins. Continue this for some time. In shaa Allah by allah's Fazal, the patient will be cured. When the healing starts, then use herbs/medicine. Giloy( Indian Tinospora) will help at a great extent.
Allah knows best
Assalam O Alaikum,
PSORIASIS needs multiple Hijamah sessions to be continued for at least 2 years; and at the same instance, the patient follows a strict diet with herbal support. The subject has been discussed earlier, seek help with the articles in this link :