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What is A 17 year old girl with acne has been taking a drug for the last two years. She now presents with blue black pigmentation of nails. The likely medication causing the above pigmentation is: and explain in detail?
There may be diffuse blue-gray, muddy appearance in sun exposed areas and hyperpigmentation of mucous membranes, teeth, nails, bones and thyroid in patients taking minocycline for longer duration. Ref: Skin Diseases and Sexually Transmitted Infection, Uday Khopkar, 6th Edition, Page 110; Handbook of Dermatologic Drug Therapy By Steven R. Feldman, Kathy C. Phelps, Kelly Campbell Verzino, Page 42; Harrison's Principles of Internal Medicine, 16th Edition, Pages 303, 1229.