My husband suffered for years from red, itchy face and scalp in the summer and the worst hair, beard, and eyebrow dandruff imaginable in the winter. Our doctor prescribed all kinds of meds for what he said was rosacea. Well, nothing helped for long and the meds were expensive. I stated to search and experiment for a way to cure or at least control whatever was happening to my husband.
Octagon soap/white vinegar controls the problem. Unfortunately, Colgate Palmolive stopped making Octagon soap several years ago. I found that Colgate Palmolive Original Green dishwashing soap has much of the same ingredients as their discontinued bar soap. http://www.palmolive.com/ingredients
Use the Palmolive "Green" dish washing soap as you would a shampoo and body wash. Do not add to bath water as it will be too diluted to work. Rinse with white (less expensive) or apple cider vinegar cut 50% with water. You must shower/wash affected areas EVERYNIGHT BEFORE BED as mites breed in darkness. You can break the chain of infestation by washing every night.
Also, we switched to a waterbed with a regular vinyl water mattress. Mites cannot live on vinyl. I wash our white sheets, blankets in any laundry detergent with a cup of bleach per load.
It's been 5 years since he started this regimen. It worked immediately and continues to work. My husband doesn't suffer anymore. This regimen controls the problem so well that he no longer has any rashes or dandruff.
Please give this a try. It's inexpensive.