Melasma is a common acquired disorder characterized by symmetric, hyperpigmented patches with an irregular outline, occurring most commonly on the face. The therapy for melasma has always been challenging and discouraging. Platelet rich plasma has been used over the last several years as an effective treatment in various surgical and medical fields. In recent years, Platelet rich plasma has also started to be used in the field of cosmetology. This study is designed to evaluate the therapeutic effect of platelet rich plasma in melasma.

Melasma is a pigmentary disorder that can be disfiguring and can cause to significant emotional stresses for sufferers, for which a universally effective treatment is still lacking. Platelet rich plasma is commonly used in dermatology and plastic surgery, especially for treating chronic wounds, ulcers, and burns. The most important contents of platelets are contained in the α-granules. Some of the bioactive substances present in the α-granules include platelet-derived growth factor, transforming growth factor -β1 and -β2epidermal growth factor, and mitogenic growth factors such as platelet-derived angiogenesis factor and fibrinogen.

transforming growth factor -β1 decreases melanogenesis via delayed extracellular signal-regulated kinase activation. The regression of melasma in a 27-years-old woman after injecting platelet rich plasma for skin rejuvenation was observed, but controlled clinical trials are still lacking to confirm this preliminary observation.

Inclusion Criteria:

• patients with melasma 18 years old or more

Exclusion Criteria:

• Patients less than 18 years.
• Pregnant females and females on oral contraceptive pills.
• Patients with a history of hypertrophic scars or keloids.
• Patients with recurrent herpes infection or with present cutaneous infection and those with facial cancer.
• Patients with blood disorders and platelet abnormalities and chronic liver disease.
• Patients using systemic chemotherapy, anticoagulation therapy and antiplatelet agents.