Foliculitis decalvans

I was diagnosticated with pulmonary cancer 9years ago, I've been taken IRESA (gefitinib) pills from 5 years ago, but from 3 months ago my body has produced "foliculitis (folliculitis) decalvans" as an allergic reaction, I've tried to stop it with the help of 3 different experts, but it just doesn't stop, the cortisone hasn't worked, and I'm truly desesperated because I'm about to loose all my hair, plus it's really itchy, plus I smell terrible, and my head is full of scars. I really need help with it. IRESA is from AstraZeneca laboratories. Thank you very much. My name is Lupita, I'm from Mexico.