Pityriasis amiantaceahttps://en.wikipedia.org/wiki/Pityriasis_amiantacea
Pityriasis amiantacea is an eczematous condition of the scalp in which thick tenaciously adherent scale infiltrates. It does not result in scarring or alopecia in most circumstances. 

Pityriasis amiantacea affects the scalp as shiny thick scales. The scales surround and bind down tufts of hair. The condition can be localised or covering over the entire scalp. Temporary alopecia and scarring alopecia may occur due to repeated removal of hairs attached to the scale. It is a rare disease.

Treatment ― OTC Drugs
*Keratolytic agents containing urea may help treat the thick scale.
#40% urea cream

*Use anti-dandruff shampoo daily.
#Ciclopirox shampoo
#Ketoconazole shampoo
#Fluocinolone shampoo
#Pyrithione zinc shampoo
#Selenium sulfide shampoo

*Apply topical OTC steroids only to the itchy areas of the scalp. Be aware that applying too much steroid to the scalp can cause folliculitis.
#Hydrocortisone cream
      References Pityriasis amiantacea - Case reports 25506575 
      NIH
      A 14-year-old male patient presented with focal masses of thick, adherent, plate like, yellow-brown scales, attached to the hair shafts, predominantly affecting the fronto-parietal area and vertex of the scalp. The underlying scalp had thick, erythematous plaques with fine, non greasy, silvery-white scaling with noncicatricial alopecia. Potassium hydroxide examination of scales and hair and culture for fungus was negative.
       Pityriasis amiantacea: a study of seven cases 27828657 
      NIH
      The disease may be secondary to any skin condition that primarily affects the scalp, including seborrheic dermatitis. Its pathogenesis remains uncertain. We aim to analyze the epidemiological and clinical profiles of patients with pityriasis amiantacea to better understand treatment responses. We identified seven cases of pityriasis amiantacea and a female predominance in a sample of 63 pediatric patients with seborrheic dermatitis followed for an average of 20.4 months. We reported a mean age of 5.9 years. Five patients were female, with a mean age of 9 years. All patients were successfully treated with topic ketoconazole.