The spatiotemporal superposition of two independent and opposite beams of laser generates a constructive interference pattern that increases the therapeutic effects in the irradiated tissue. Patient suffering pain from diagnosed carpal tunnel syndrome will receive conventional or interferential laser therapy. This is a comparative randomized and double blind clinical study. Two identical lasers in near infrared range will be used. Frequency of sessions: daily. Irradiated technique: manual, contact and punctual. Pain will be evaluated by visual analog scale at rest and during analytical wrist movement. Disability will be evaluated by the DASH and BOSTON questionnaire. Evaluation will take place at pre and post-treatment times.