Editing Intense pulsed light (section)

===Efficacy===
In August 1997, IPL was reported to have permanently removed terminal hair in two patients who underwent multiple treatments to their beards.<ref name=":0" /> In October of that year, the first IPL system developed for hair removal and resulted in 60% hair reduction after 12 weeks.<ref name=DS>{{cite journal|last1=Gold|first1=Michael H.|title=Long-term epilation using the EpiLight broad band, intense pulsed light Hair Removal System|journal=Dermatologic Surgery|date=October 1997|volume=23|issue=10|pages=909–913|doi=10.1111/j.1524-4725.1997.tb00746.x|pmid=9357500|last2=Bell|first2=Michael W.|last3=Foster|first3=Teresa D.|last4=Street|first4=Sherri|s2cid=25398697}}</ref>

It is important to note that these studies utilized a variety of IPL devices on patients with various hair types, skin types, and targeted skin areas. Thus the results are not directly comparable.

According to the FDA, permanent hair reduction means the "long-term, stable reduction in the number of hairs regrowing after a treatment regime." In other words, the number of hairs regrowing must be consistently greater than the duration of the complete growth cycle of hair follicles, which varies from four to twelve months by body location.<ref>{{cite web|url=https://www.fda.gov/radiation-emittingproducts/resourcesforyouradiationemittingproducts/ucm252761.htm#1 |title=Laser Facts |publisher=FDA |access-date=23 September 2014 |url-status=dead |archive-url=https://web.archive.org/web/20140912203435/https://www.fda.gov/Radiation-EmittingProducts/ResourcesforYouRadiationEmittingProducts/ucm252761.htm |archive-date=September 12, 2014 }}</ref> IPL has been found to be much less effective than laser hair removal; however, many patients experience satisfaction with significant hair reduction.<ref name=":3" />

A 2006 article in the journal ''[[Lasers in Medical Science]]'' compared IPL and both alexandrite and diode lasers. The review found no statistical difference in effectiveness, but a higher incidence of side effects with diode laser treatment. Hair reduction after six months was reported as 68.75% for alexandrite lasers, 71.71% for diode lasers, and 66.96% for IPL. Side effects were reported as 9.5% for alexandrite lasers, 28.9% for diode lasers, and 15.3% for IPL. All side effects were found to be temporary and even pigmentation changes returned to normal within six months.<ref>{{cite journal|last1 = Toosi|first1 = Parviz|title = A comparison study of the efficacy and side effects of different light sources in hair removal|journal = Lasers in Medical Science|date = April 2006|volume = 21|issue = 1|pages = 1–4|doi = 10.1007/s10103-006-0373-2|pmid = 16583183|last2 = Sadighha|first2 = Afshin|last3 = Sharifian|first3 = Ali|last4 = Razavi|first4 = Gita Meshkat|s2cid = 10093379}}</ref>

A 2009 study evaluated the rate of hair removal after a second generation IPL source. Results found that patients had 75% hair reduction after four months, and up to 80% after eight months.<ref>{{cite journal|last=Smith|first=S.R.|author2=Y. Tse|author3=S.K. Adsit|display-authors=etal|year=1998|title=Long-term results of hair photo-epilation|journal=Lasers Surg Med|page=43}}</ref><ref>{{cite journal|last=Troilus|first=A.|author2=Troilus C|date=September 1999|title=Hair removal with a second generation broad spectrum intense pulsed light source—a long term follow-up|journal=J Cutan Laser Ther|volume=1|issue=3|pages=173–178|doi=10.1080/14628839950516832|pmid=11360414}}</ref>