I had dandruff before 4 months. On using Coaltaz-KZ shampoo & Clop-s every alternate day-it is practically over. Now my skin gets dried & irritated-resulting redness in head & neck. It goes aways on next day. However Skin Specialist prescribed to continue treatment-life time. He also advised not to use any hair oil. What is long term adverse effect & whether frequency can be reduced-once in week/month. What is alternative? Would you advise for any hair-oil &/or another Shampoo? Kindly note that I have no more irritation & scalp due to dandruff. Please help.