Periorbital hyperchromia (POH) or periorbital hyperpigmentation, commonly known as "dark circles", is a relatively common condition and a frequent reason for dermatological consultation. It is defined as brown-colored pigmentation, ranging from light to dark, which mainly involves the lower eyelids. POH affects individuals over a wide age range, including both sexes and all ethnicities, and is associated with a tired and aged facial appearance. The most commonly affected people are those with the highest skin phototypes. Although the prevalence is similar between sexes and age groups, POH is a more frequent complaint in women. The dark circles characteristic of POH can negatively impact patients' quality of life, although it is not a condition associated with morbidity. Despite its high prevalence, only a few well-designed studies were done to evaluate its therapeutic options. The intense pulsed light (IPL) and the thioglycolic acid are safe treatment options and promote the improvement of dark circles, but it is not known if one treatment differs from the other in relation to efficacy and adverse effects.

It is a blinded randomized clinical trial, with the sample size calculated of 29 subjects, already considering 10% of possible losses and refusals. For this number was considered 80% power and significance level of 5%.

Selected patients will be invited to participate and informed about the characteristics of the study. If they do, they must sign a free and informed consent form.

At the first visit, some demographic data will be collected, including sex, age, phototype, history of smoking and / or alcohol consumption, family history of periocular hyperpigmentation, personal or family history of allergies and hours of sleep, for instance.Photographic registration will be done in a standardized way. After completion of the study, the photographs will be evaluated blindly by two evaluators, and they will not know before what therapeutic modality was adopted in each periorbital region. Clinical evaluation will be obtained through the application of the Global Aesthetic Improvement Scale (with the following grades: much better, better, better, no change, worse) and visual analogue scale for clinical improvement from 0 (no improvement) to 10 (complete improvement), both with monthly evaluations. Each patient will be submitted to the two proposed therapies, being a therapeutic procedure in the right periocular region and another in the left periocular region. Each periocular region will be randomized using the random.org program for treatment with 10% thioglycolic acid peeling or IPL. Both therapies will be performed at the same time in the monthly visits, totaling 3 months of treatment (3 sessions of IPL and 3 sessions of thioglycolic acid). The first visit will be for collection of demographic data, physical examination record, colorimetry and questionnaire completion. Visits 2, 3 and 4 will be for the treatments and the visit in month 5 will be for evaluation of the results.

Inclusion Criteria:

• Patients with periocular hyperchromia diagnosed by clinical examination. The volunteers included must have a pigmentary component, which may or may not present the anatomical component, determined through physical examination with the aid of dermoscopy, to be performed at the inclusion study visit.

Exclusion Criteria:

• Pregnant patients, active collagenase patients, patients using photosensitizing substances and areas with bacterial or viral infections, patients with scars or tattoos at the evaluated site, patients undergoing any treatment modality for periocular hyperpigmentation in the last 3 months.

There will be 2 blinded evaluators who will not know which side of the periorbital hyperchromia (right or left) received which treatment (IPL or peeling of 10% thioglycolic acid). They will do the evaluation through photographs, comparing the photos before the treatments with the photos after 1, 2 and 3 sessions after the treatments, without knowing what therapeutic modality was adopted in each periorbital region.