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What is A 17 year old girl with Acne has been taking a drug for the last two years. Show now presents with blue black pigmentation of nails. The likely medication causing the above pigmentation is and explain in detail?
B i.e. MinocyclineAmongst tetracyclines (tetracycline/ minocycline/ doxycycline) pigmentation is most commonly associated with minocyclineQ. A diffuse blue-black/blue- gray/ muddy hyper pigmentationQ is an uncommon but troublesome side effect of prolonged minocycline therapy. Sites of involvement include sun exposed skin, mucus membranes (eg conjunctiva), nails, teeth, sclera, thyroid & bonesQ.Two side effects unique to minocycline are drug induced lupus & blue black pigmentation. Tetracycline induced nail discolouration is yellow.