Intense pulsed light, commonly abbreviated as IPL, is a technology used by beauty studios
and medical practitioners to perform various skin treatments including hair removal and
photorejuvenation. The technology utilises a broad spectrum lightsource, with a general
spectral range of 515 to 1200 nm. Various cutoff filters are commonly used to filter
out lower frequencies and narrow this spectrum to target specific structures and chromophores.
Because of the broad spectrum of the IPL light source they are unique, as opposed to lasers,
in the ability to filter the light spectrum to target various chromophores in the skin.
Definition Intense pulsed light describes the use of
intense pulses of non-coherent light distributed over a range of wavelengths from 500 nm to
1200 nm, for removal of hair and other purposes. A related but distinct technique is laser
hair removal; the primary difference is that laser treatment uses laser-generated coherent
and monochromatic light. Regulations governing IPL and laser hair removal
vary by jurisdiction. The two techniques are often confused. There
are many names used for intense pulsed light treatments. IPL and equivalent treatments
are referred to as I2PL, UPL, VPL, SPL, SPFT, SPTF, SIPL, PTF, CPL, AFT, E-Light, ELOS,
M-Light, and other names. The name "Intense Pulse Light" is not known to be a registered
trademark. A distinction is sometimes made between beauty-grade
and medical-grade machines. This distinction is mainly to get around regulations. Under
the CE system no such distinction exists. Hair removal
Permanence and efficiency The first use of a specific IPL system developed
for hair removal is reported in the literature in 1997. Effectiveness, reported as hair count
reduction, was found to be ~60%(12 weeks), 75%(1 year), 60%(2 year). The study utilized
31 patients. A study by Fitzpatrick and Goldman reported
that 5 treatments at 4 week intervals produced reductions of approximately 60%, 45%, and
40% at 4, 8, and 12 weeks following the final treatment. This study included 50 subjects.
Smith et al. reported findings in 90 patients using four biweekly treatments. Effectiveness
was reported as 81% reduction following the 3rd treatment, 63% at four months, and 48%
at 6 months. Weiss et al., studied 23 patients using a
single treatment and an additional 48 patients receiving 2 treatments 1 month apart. Patients
showed hair reduction of 63% with one treatment. Two treatment patients showed 64% hair reduction
directly after the second treatment, which declined to 33% at 6 months.
Weir and Woo reported 42% reduction in skin types IV and 37% in skin types V at 15-months
after a single treatment. Troilus and Troilus studied 10 patients using
four treatment sessions at 1-month intervals. Reported hair reduction was 74.7%, and 80.2%.
Schroeter et al. studied 40 patients receiving an average of 6 treatment sessions and found
a hair reduction of 76.7%. Sadick et al. studied 67 patients and found
hair reductions after one treatment of 61% at 3 months, 58% at 3–6 months, and 48%
at 6 months or more. Multiple therapies, showed hair reduction of 47% at 3 months, 56% at
3–6 months, and 64% at 6 months or more. In a subsequent report, 34 patients showed
hair reduction of 76% after 4 treatments at 21.1 months.
Bjerring et al. studied 31 patients using 3 treatments at 2 month intervals and found
49.3% hair reduction after 6 months. It is important to note that these studies
utilized a variety of IPL devices on various skin areas, and used patients with varying
hair and skin types. Thus the results are not directly comparable. In evaluating these
results it is also important to remember that even a reduction of 75% indicates that 25%
of the hair regrew after treatment. "Permanent hair removal" in these studies, as defined
by the FDA, means the "long-term, stable reduction in the number of hairs regrowing after a treatment
regime". The number of hairs regrowing must be stable over time greater than the duration
of the complete growth cycle of hair follicles, which varies from four to twelve months according
to body location. No treatment to date has shown the ability to permanently eliminate
all hair growth forever, however many patients experience a significant and permanent reduction
in hair growth and are happy with their results. Clinical Comparison of Effectiveness
A 2006 review 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 based treatment. Hair reduction
after 6 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 6 months.
The hair growth cycle The focused, broad-spectrum light is applied
to the surface of the skin by way of either a hand-held wand or an articulated arm. This
light travels through the skin until it strikes the hair shafts or the bulb of the hair. The
bulb is usually where the highest concentration of melanin is located, as opposed to the rest
of the hair shaft. As the light is converted to heat energy, the bulb and most of the hair
shaft are instantly heated. The intense heat radiated by the hair also
destroys the hair-producing papilla. It is also claimed that direct light-heat conversion
occurs directly in the darker colored capillaries that bring nourishing blood vessels to the
follicle. Contrary to what is often claimed, photoepilation is not a permanent hair removal
method but a permanent hair reduction method. This means that although IPL treatments with
these devices will permanently reduce the total number of body hairs, they will not
result in a permanent removal of all hair. The argument of permanent hair removal against
permanent hair reductions is only of relevance in the USA because of the wording on the FDA
certificate. At any one time, not all hair follicles are
‘active’, and only active hair follicles can be affected by the treatment. ‘Inactive’
hair follicles can be treated as they become ‘active’ over time. For IPL treatments
an average of 8–10 treatments are required to remove most visible hair.
Contra-indications Certain skin conditions, health irregularities,
and medications can impact whether it is safe for a person to receive a light based hair
removal treatment. This list applies to both IPL and conventional laser treatments.
Recent use of depilatory creams or sprays Recent waxing, tweezing, or sugaring
Contagious skin diseases: not always contraindicated but requires special preparation
Herpes I and II in the area to be treated: not always contraindicated but requires special
preparation Skin trauma, lesions, sores or open wounds
Keloid or hypertrophic scarring Moles or skin cancer: treatment can blanch
skin marks, making melanoma difficult to detect Sunburn
Suntan, real or fake: hyperstimulates melanin in skin which provides a confusing target
for light Epilepsy or other seizures potentially caused
by flashing light Polycystic Ovarian Syndrome: condition needs
to be normalised with medication before treatment Hyperthyroidism: condition needs to be normalised
with medication before treatment Breastfeeding and pregnancy: increased hormone
levels greatly decrease treatment efficacy Hirsutism: not contraindicated but will require
a greater number of treatments Tattoos or permanent makeup in area to be
treated Photo-sensitising topical creams or medication:
Tetracycline, Minomycin, Doxycycline, St John's Wort, any citrus essential oils
Black garments: can singe or combust if struck directly by the light flash
Pain during treatment: if a person feels more than mild discomfort during treatment, the
machine settings are wrong According to Remington, manufacturer of an
IPL hair remover, all IPL and laser devices should only be used on light to medium skin
tones, and work best on darker hair. Treatment protocol
No common treatment protocol exist and it depends on the equipment used and skin type
of the patient/client. Commonly the treatment area needs to be clean, shaved and free of
sunburn. Treatment sessions are usually 4 to 6 weeks apart for treatments at a beauty
salon. Other uses
IPL technology is employed in the treatment of medical disorders of the skin including:
Sun damage induced dyspigmentation and vascular changes
Poikiloderma of Civatte Acne Rosacea
Broken capillaries/telangiectases Vascular Lesions
Pigmented Lesions See also
Hair removal Electrolysis
Laser hair removal References
External links FDA page on IPL and Laser epilation