Cosmelan is a type of facial mask given by a medical esthetician, dermatologist or other health care professional. Though effective at lessening the appearance of dark skin spots in some patients, Cosmelan poses a risk for side effects.

Redness and flaking of your skin is common after a Cosmelan treatment, reports New Image Cosmetic Surgery of San Diego.

Less common side effects of Cosmelan are also possible, including itching and tightness of your skin.

The skin irritation possible with Cosmelan typically develops within the first day of your treatment and may last up to two weeks, according to La Jolla Dermatology.

Your skin practitioner is likely to give you a skin cream that contains Vitamin K, which should help reduce many of the side effects of Cosmelan when used as described, according to La Jolla Dermatology.

To prevent severe skin side effects like blistering, avoid combining Cosmelan with any other treatment for skin hyperpigmentation, cautions New Image Cosmetic Surgery of San Diego.