<prompt> Which is used in keratinised skin:Salicylic acidFluconazoleSteroidsCoal tar  <response>: Ans: a Salicylic acid Ref: Tripathi, 5th ed, p.Keratolytics dissolve the intercellular substance in the homy layer of the skin.The epidermal cells swell, soften then desquamate.These drugs are used on hyperkeratotic lesions like corns, warts, psoriasis, chronic dermatitis, ringworm athletes foot.They include:a. Salicylic acid- as 10-20 solution in alcohol or propylene glycol for dissolving com.b. Resorcinol- It has antiseptic, antifungal, local irritant keratolytic properties. 