An 81-year-old woman presented to our clinic with painless hyperpigmented blue-gray patches on both lower legs (Fig. 1), without associated pruritis. She had been diagnosed with vertebral osteomyelitis 8 months previously and was on long-term minocycline as suppressive therapy (100 mg orally twice a day). She was also taking amlodipine for hypertension, zolpidem for insomnia, and donepezil for Alzheimer's disease. Physical examination revealed that the hyperpigmentation was confined to the lower legs (Fig.