Several recent studies have documented the efficacy and safety of minocycli
ne in the treatment of mild rheumatoid arthritis. Reported side effects ten
d to be mild, with gastrointestinal disturbances, headaches, vestibular dys
function, and photosensitive rashes being the most common. Hyperpigmentatio
n of skin and other structures has also been reported but seems to be uncom
mon and usually dose-related. The different types of skin hyperpigmentation
are reviewed, including their histopathologic and clinical distinctions, p
ossible predisposing factors, and treatment.
Our experience suggests that steroid use, advanced age, cumulative minocycl
ine dosage, and possibly the brand of minocycline may be predisposing risk
factors for developing hyperpigmentation. It is quite possible that this ad
verse effect is more common than previously recognized, and we suggest that
physicians prescribing minocycline be observant for skin hyperpigmentation
. Although most of our patients with hyperpigmentation chose to continue th
e medication (61%), it must be discontinued for the hyperpigmentation to re
solve.