68-Year-Old Woman Develops Blue-Gray Skin Discoloration After Taking Minocycline

A 68-year-old woman developed blue-gray hyperpigmentation on her arms and legs two weeks after beginning treatment with oral minocycline for rosacea, according to a case report in the New England Journal of Medicine. The woman sought medical care after the dark patches on her limbs persisted for six weeks.

She had been prescribed 100 mg daily of the tetracycline antibiotic, which is commonly used to treat the acne-like bumps associated with rosacea as well as other bacterial infections. Minocycline is sold under brand names including Dynacin, Minocin and Solodyn.

It is widely prescribed for acne, pneumonia and other conditions. A recent study also examined its potential use in treating panic disorder in patients who do not respond to standard psychiatric medications.

Common side effects of minocycline include dizziness, nausea, headache, fatigue and increased skin sensitivity to sunlight. Hyperpigmentation, which can turn skin blue-gray or blue-black, occurs in 3 to 15 percent of patients but typically develops over months rather than weeks.

Medical staff advised the woman to discontinue the medication and avoid sun exposure. Six months after stopping treatment, the hyperpigmentation had abated somewhat but had not disappeared completely. The patient was diagnosed with Type II minocycline-induced hyperpigmentation, which causes blue or gray discoloration.

Three other types exist: Type I produces blue-black spots in scar tissue, Type III causes muddy brown spots on sun-exposed skin, and Type IV produces muddy brown spots in scar tissue.

Rosacea is a chronic inflammatory skin condition that causes facial redness, acne-like bumps and textural changes. It has no single cause and requires individualized treatment approaches. In addition to hyperpigmentation, minocycline can cause other serious skin reactions including erythema multiforme and Stevens-Johnson syndrome.

The latter is a rare disorder that begins with flu-like symptoms followed by a blistering rash and is fatal in 10 percent of cases. The antibiotic has been used in humans for more than 50 years and is generally considered safe. Patients taking the medication should be informed of the risk of skin discoloration, which in some cases may require laser treatments for removal.