The study was terminated early after interim analysis of 48 participants, which showed significant group differences with 80% power, making further enrollment unnecessary.

The goal of this clinical trial is to compare the effectiveness of two hair removal techniques: Intense Pulsed Light (IPL) and Diode Laser in woman underarm. .

Main Questions:

• Determine the thread count in a 4cm² quadrant in the central axillary region before each session, 4-6 weeks after the last session and at follow-up 30 weeks after the last session;
• Measure the thickness of the hair before each session, 4-6 weeks after the last session and at follow-up 6 months after the last session;
• Compare the level of pain during procedures;
• Evaluate the volunteer's level of satisfaction after the end of the sessions programmed by the study;
• Evaluate quality of life and self-image before and after the end of the sessions programmed by the study;
• Evaluate the maintenance of results 6 months after the last procedure performed.

Researchers will compare IPL and Diode laser to see if hair removal is similar at short and long time course.

The IPL treatment will be applied to one axilla. The 800nm Diode Laser treatment will be applied to the other axilla. Treatment allocation will be randomized for each participant. Participants will undergo monthly sessions for four months, totaling four treatments. Follow-up assessments will occur 30 days and 6 months after the final session.

This is a randomized controlled trial of hair removal in axilla for women, being intense pulsed light compared to diode laser.

The session frequency will be once a month for 4 months, totaling 4 treatments. There will be a follow-up at 30 days and 6 months after the end of the treatment.

After the evaluations and photographs, the armpits will be cleaned with 0.5% alcoholic chlorhexidine and will be shaved with a disposable razor blade. Neutral water-based gel will be applied to the region to receive the treatment. Patients will be instructed not to perform any trichotomy procedures in the region during the research period.

The treatment technique will be punctual where the applicator will be kept in full contact with the skin at 90° and moved to the next point after deposition of energy over the entire treatment area until the defined energy is delivered. The applicator tip will be cooled as much as the equipment allows.

Inclusion Criteria:

• Female patients,
• aged 18 and older,
• with a complaint of hair in the axillary region,
• Fitzpatrick skin phototype I to IV,
• presenting dark hair

Exclusion Criteria:

• Patients who have used medications that alter hair production,
• Patients who have used medications that are photosensitizing,
• Patients who have used isotretinoin or vitamin A-synthesized acids, antibiotics such as tetracycline,
• Patients using anticoagulant
• Patients with vitiligo or epilepsy,
• Pregnant or lactating individuals,
• those with active herpes,
• Patient with history of tumors,
• Patient with axillary scarring (hyper or hypotrophic),
• Patient who have used another method of hair removal involving complete hair removal by pulling with a minimum period of 30 days from the date of the initial assessment, or have used another laser hair removal method in the treatment area,
• Immunocompromised patients,
• Patients with sun-sensitive skin with inflammation,
• Individuals with psoriasis,
• Patients with tattoos on the application site,
• Patients who have undergone ovary removal or have reached menopause

participants will receive both treatments in right and left axilla, and they won´t know which treatment will be performed at each side.

The outcome assessor won´t know which treatment was performed at the axilla.