Methacycline hyperpigmentation: a five-year follow-up.

A five-year follow-up is presented of a unique material of patients who acquired a greyish black hyperpigmentation during long-term methacycline therapy for chronic bronchitis. The melanosis disappeared in cases in which tetracycline therapy was discontinued during the observation period but not in those in which doxycycline had been substituted. In two autopsy cases pigment deposits were also found in cartilage and atherosclerotic lesions. Overall clinical and microscopic findings suggest a similarity to the pigmentation occurring in iatrogenic ochronosis.