Diltiazem can produce slate-gray to blue-gray reticulated hyperpigmentation.5 Other drugs that can induce slate-gray macules or patches include amiodarone, chlorpromazine, imipramine, and desipramine.5
Treatment is simple, resolution takes time
The treatment for this condition is cessation of minocycline use. Pigmentation fades slowly and may persist for years. There has been successful treatment of type I and III minocycline-induced hyperpigmentation with the alexandrite 755 nm Q-switched laser combined with fractional photothermolysis.3,6 Unfortunately, insurance coverage is limited because these treatments are cosmetic in nature.
Given that hyperpigmentation is a known adverse effect of minocycline use, it’s important to counsel patients about the possibility prior to initiating treatment. It’s also important to monitor for signs of changing pigmentation to prevent psychological distress.
In this case, a biopsy was deemed unnecessary, as the antibiotic was the most likely cause of the pigmentation. The patient’s outpatient dermatologist recommended changing therapy if a medically appropriate alternative was available. Doxycycline would have been a reasonable alternative; however, the patient died shortly after his presentation to our hospital due to his multiple comorbidities.
CORRESPONDENCE
Bich-May Nguyen, MD, MPH, 14023 Southwest Freeway, Sugar Land, TX 77478; Bich-May.Nguyen@memorialhermann.org