Efficacy of Intense Pulsed Light vs. Triple Wavelength Diode Laser in Hair Reduction

To compare the effectiveness of triple wavelength diode laser (TWDL; 755 nm, 808 nm, and 1,064 nm) versus intense pulsed light (IPL; 400-1,200 nm) for hair reduction, measured by percentage reduction in hair growth after 4 months of treatment, and to evaluate the side effect profile of both modalities in the Pakistani population.

An experimental comparative study. Place and Duration of the Study: Department of Dermatology, Dow International of Medical College, Dow University Hospital, Ojha Campus, Karachi, Pakistan, January to July 2025.

One hundred and twenty-eight patients aged 18-60 years of Fitzpatrick type II to type V, with hypertrichosis/idiopathic hirsutism, were randomised into two groups: IPL (n = 60) and TWDL (n = 68). Each received four monthly treatment sessions. The primary outcome was hair reduction assessed by the Global Aesthetic Improvement Scale (GAIS) after the fourth session. Secondary outcomes included early efficacy and safety assessed through adverse events. Data were analysed using the chi-square test.

After four sessions, 39.7% of TWDL-treated patients achieved excellent GAIS responses compared with 20.0% in the IPL group, while good responses were observed in 47.1% and 60.0% of patients, respectively (p = 0.081). Early efficacy at 2 months favoured the TWDL, with 36.7% achieving good-to-excellent hair reduction, compared with none in the IPL group (p <0.001). Adverse events were more common in the IPL group, with redness, pain, and burning being the most frequently reported.

Both modalities reduced hair growth. The TWDL showed superior early efficacy and a more favourable safety profile; however, the difference after four months was not statistically significant.

Hypertrichosis, Hirsutism, Triple wavelength diode laser, Intense pulsed light, Hair reduction.