What should you know about infrared laser diode?

A diode is the light source inside the device. Infrared wavelengths can pass into the skin far enough to reach pigment in the hair shaft and follicle. The absorbed energy becomes heat, which can reduce the follicle’s ability to produce another hair. The device is not the same as an ordinary lamp, and its effect depends on wavelength, pulse delivery, skin tone, hair colour, and the treatment area.

Because hair cycles through growth phases, a course may be recommended rather than one isolated visit. Fine, pale, grey, red, or white hair may respond differently because it contains less of the pigment that absorbs the light. A clinician should distinguish a diode laser from other light-based devices and check whether the planned target is appropriate.

Before treatment, disclose recent tanning, medicines that increase light sensitivity, a history of cold sores, active rashes, and any tendency to form raised scars. Avoid plucking or waxing the target hair when advised, because the follicle needs to remain present for the light to reach it. Follow the clinic’s shaving and cleansing instructions.

During treatment, use the supplied eye protection and report excessive heat immediately. Afterwards, mild redness or swelling around follicles can occur. Keep the area cool, use gentle products, avoid deliberate sun exposure, and apply broad-spectrum sunscreen to exposed skin. Do not pick crusting or use strong exfoliants until the skin has settled. Read more about [Laser Hair Removal](/treatments/laser-and-energy/laser-hair-removal/).

Contact the treating clinic promptly for blistering, marked pain, spreading swelling, drainage, or skin colour changes that worsen rather than settle. Seek urgent care for facial swelling with breathing difficulty, faintness, or a widespread allergic reaction. A new changing lesion should be assessed separately rather than treated as a cosmetic target.

Ask which wavelength and cooling method will be used, what result is realistic for your hair and skin type, how many visits may be considered, and which medicines or recent sun exposure should delay treatment. You can also ask whether a patch test is appropriate and who will manage a burn or pigment change if one develops.