I am hypothyroid and have deficiency of vit b12 and vit D. My neck and face skin tone looks different from the entire body. I have hyperpigmentation around mouth and acne spots on cheeks too. I have met a dermatologist and He said I have acanthosis nigricans. He prescribed me tab nexna, lacne and clindapene. Apart from that I am using demelan too. Its been a month but unable to see any difference. Kindly guide how to get rid of it by the medicine mentioned as if I am taking them wrong. Like I am confused between nugen tab and b12 capsule. Which medicine to take first, before meal or after meal. How long to use clindapene and demelan on face and neck.