If you suffer from scalp psorasis your dandruff will typically be white/silvery and scaley. During a break out your skin can be red and inflamed and often itches. You will suffer these outbreaks periodically with bursts of relapses.
The exact cause of scalp psoriasis is still unknown, however popular shampoos often include salicylic acid to help soften the dandruff or coal tar to help prevent the dandruff forming. Make sure you choose gentle ingredients in your shampoos as the harsher chemicals may dry your scalp, confusing the condition further. We can help out there by monitoring the shampoos for 90 or so known contact allergens.Read more about psoriasis.