Allergic reactions= inflammation,Inflammation can be caused by numerous things.

Have you got health insurance? If so strongly recommend you a trichologist, someone who specializes in scalps.

Using steroids for more than a month or two is absolutely insane. You are not treating the cause you are just stifling the inflammation (clearly not well if you had to up the dose and try for two years) because that’s what steroids do. Read the list it came with. “Used to treat SYMPTOMS of allergic reactions”

Find the cause and cure it. If your head is so greasy you can push out oil and blackheads, then it sounds like your scalps follicles are severely clogged. water rinse every single day to remove excess oils without completely stripping your head helps keep build up down. With warm water, not hot. This action of massaging your scalp allows for buildup to not accumulate so much in your follicles.

There is an oiling cleansing technique used by dermatologists that involves using warmed oil and a hot towel to open pores and dislodge clogged sebum (blackheads) The idea being that oil will dissolve with other oils. People have experienced really nice results with this to treat clogged follicles. And you can do it at home instead of paying someone.

Back to the cause. It could be so many things, and again- something you really should be tested for so you can find the right course of curing it, not just treating it. Seborrheic dermatitis is simply an overgrowth of fungus or bacteria on your head. This is actually easily treated with at home remedies. Pure and diluted tea tree oil is great, but it depends what else is in the tea tree oil products you are using. Are all 3 products you use from a brand?

Apple cider vinegar is thought to help by rebalancing the ph of your scalp to what it naturally is, creating a suitable home for the “good bacteria” on your scalp to grow while eliminating fungus since they can’t survive well in acidic environments, and it gives the bacteria a chance to take them over. There is a recent study that claims that bacteria can also be a culprit ( up until now yeast and fungus was considered top causes) so what’s a solution then? I like a strong approach. Hydrogen peroxide (3%, diluted) as a prewash to that oiling technique will disinfect the area from bacteria, yeast, and fungi. It’s a known dandruff cure. Peroxide is very drying. The oil cleansing after a disinfectant would allow for your scalp to dislodge some follicles ( it takes a few sessions, you don’t want to be overly vigorous if your scalp is hurting!) while also leaving some oil to make sure your scalp isn’t freaking out and producing even more.

Ph balance over time can be restored naturally but a cheap little spray bottle from the dollar store filled with diluted apple cider vinegar can be a good last light spritz to the scalp to help move things along.

I hope this was informative. Do you have hard water in your area?