Q-switched 532 nm Nd:YAG laser therapy for physiological lip hyperpigmentation: novel classification, efficacy, and safety.

BACKGROUND Physiological lip hyperpigmentation (PLH) is a common cosmetic concern in the Middle East and Asia. It is characterized by homogeneous symmetric diffuse hyperpigmentation affecting both lips. There is no satisfactory treatment for this condition. The aim of this study is to evaluate the efficacy and safety of Q-switched (QS) 532 nm Nd:YAG laser for PLH. METHODS A total of 30 patients with clinical diagnosis of PLH were retrospectively reviewed and included in the study. Patients underwent at least one laser treatment using QS 532 nm with a minimum follow up of six months. Laser parameters were as follows: spot size 2-3 mm, pulse duration 20 ns, fluence 2-4 J/cm2. One to three sessions were performed depending on clinical response. Two methods were used for assessment: patient satisfaction and independent physician assessment. PLH was classified as grade 1 (upper lip fully affected plus only border of lower lip), grade 2 (upper lip fully affected plus most of lower lip), and grade 3 (majority of both lips hyperpigmented). RESULTS Excellent (>75% improvement) response was achieved in 30% of patients. Good (51-75% improvement) response was seen in 37% and 43% of patients according to patient satisfaction and independent physician assessment, respectively. Majority of patients required only one treatment session. Reactivation of herpes labialis occurred in two patients, and mottled hypopigmentation in three patients. None of the patients developed persistent hyperpigmentation or scarring. CONCLUSIONS PLH can be effectively treated with QS 532 nm Nd:YAG laser and is well tolerated by patients.