After observing a patient with adult-onset tooth discoloration coincident with minocycline administration, we retrospectively surveyed a cohort of patients with severe cystic acne during therapeutic trials with isotretinoin. Four of 72 patients who had minocycline therapy during adolescence were found to have minocycline-associated tooth discoloration, which occurred in one case after only four weeks of treatment. Thus, minocycline must be considered as an uncommon cause of tooth staining in adults.
Poliak SC, DiGiovanna JJ, Gross EG, Gantt G, Peck GL. Minocycline-Associated Tooth Discoloration in Young Adults. JAMA. 1985;254(20):2930-2932. doi:10.1001/jama.1985.03360200082032