Dish soap eliminates itching right away, too. It's a natural brand common at grocery stores. The unscented is what I use most but the lavender works, too. It relieves itching and heals the sores when used every other day. I have very long hair and the soap has not damaged it.
Another big name dish soap does not work nearly as well.
I started taking selenium and flush-type niacin and getting more protein and my scalp is feeling better. To accentuate the flush (which feels so good as it creeps up the back of your neck and across the top of your head! ) chew the niacin and swallow it with some water and then chew on a 1 inch piece of fresh ginger. Do it on an empty stomach. I get up early in the morning and do it and then go back to bed and let it do its thing. I also take 3 drops Lugol's 5% and magnesium with it. There is a store brand that is marketed as a chelated magnesium that helps with sleep and bone health. It knocks me out and has a pleasant relaxing effect for a few hours after I finally get up.
If you wear hats, headbands, or ponytails that trap heat and moisture they may be causing the condition. Just washing them after each use may resolve the condition.