Hair loss

I have only had scalp psoriasis for about 6 months, I tried a few treatments including Dovobet, I used Etrivex shampoo for 7 days and the psoriasis has all gone, that was 3 weeks ago. I still use Etrivex once a week just to make sure. My problem is hair loss its still falling out and I'm almost bald on the top of my head. If anyone has suffered hair loss can they let me know how long it was before it started to grow back, or if it didn't! Many thanks. I have had small lumps on my body but Dovobet seems to clear them up very quickly.