Intense pulsed light source (IPLS) treatment for hair removal
Since time immemorial, ‘body hair’ has caused women
enough embarrassment; they have tried and tested hundreds of home
remedies and cosmetic therapies to get rid of their hairy look.
Some of these proved immensely effective (methods such as shaving,
plucking, mechanical and chemical dermabrasion), at least temporarily.
The unwanted hair, however, would make a comeback, requiring
women to go through another grueling session of hair removal.
Things started looking up with the arrival of the age of cosmetic
perfection, when dermatologists and cosmetic surgeons started
experimenting with various new methods of hair removal. In their
search for newer techniques they evolved methods such as needle
and laser epilation. These proved successful in containing the
re-growth of body hair for prolonged periods.
Intense pulsed light source (IPLS) epilation treatment, using
incoherent light of a broadband spectrum in the range of 500 to
1200 nanometers, is a more recent development in hair removal.
Technically, it is not a laser hair removal system – the
light involved is not laser light, but, as the name suggests,
a very intense pulsating light which has a similar effect to laser
light. The success with this treatment lies in the fact that its
broad range of technical variables allows the light treatment
to be changed (in intensity or the way the light pulses) as appropriate
for the nature of the skin and hair follicles to be removed in
each individual. It is a highly effective long-term hair reduction
method, with very few negative side effects. The device or the
Intense Pulsed Light Source is also referred to as a Flashlamp,
Epilight or Photoderm VL.
The IPLS (Intense Pulsed Light Source) Treatment
IPLS epilation is based on the principle of selective photothermolysis – the
intense pulsed light energy is absorbed by the chromophore, in
this case melanin pigment, concentrated in and around the hair
follicle bulb. The heat generated in the process destroys the
hair follicle as well as the immediate area around it.
The tissue penetration power of visible light depends on the
wavelength; in fact, longer wavelengths infiltrate deeper into
the skin. The IPLS epilation method uses different cut-off filters
(515, 550, 570, 590, 615, 695 and 755 nanometer filters) to adjust
or alter the penetration power of the light so that it matches
the specific target – both in size as well as skin depth – whether
it is hair follicle bulb or its adjoining bulge area. Usage of
different cut-off filters, at the same time, helps adjust the
treatment parameters in accordance with different skin types.
Pulse duration can also be varied – ranging between 2 and
25 ms; however, under every circumstance the pulse duration has
to be less than the thermal relaxation time of the target tissues.
Otherwise, the target tissues will cool off between each light
pulse, hampering the ultimate effect. The aim is to build up heat
in the hair follicle to a high enough level to “cook” and
destroy the hair growing cells.
The IPLS technique, at times, requires the use of more than a
single pulse. Trains of two to three pulses at regular intervals
reasonably enhance the selectivity of the light, so that it focuses
on the target hair follicle tissues all the time and is not deflected
or scattered in the skin. The size of the IPLS device also plays
a vital role in enhancing the selectivity by reducing unnecessary
When taking IPLS treatment, a cooling skin gel is required. The
aim is to make the darkly pigmented hair follicles heat up so
they become destroyed, but skin beyond the hair follicles should
not be affected. The gel performs a dual function – boosting
the penetration power of the light into the hair follicles while
absorbing the heat from the skin.
The Maastricht Study to Prove the Effectiveness of IPLS System
A study was conducted in the Medical Center, Maastricht, (Netherlands),
to test the effectiveness of IPLS system in long-term hair reduction.
Seventy hirsute female patients, aged 18 to 67 years chosen at
random, were treated with IPLS epilation therapy (using first
generation flash lamps).
To begin with, the patients were categorized depending on their
skin types (Fitzpatrick I to V). The patients were then asked
to shave off the body hair 1 or 2 days before the commencement
of the treatment. Patients were also advised to use sun blocker
creams for the duration of the treatment. Sun block stops the
skin from tanning – this is good for IPLS and laser hair
removal as they both work by heating up pigment. If there is pigment
in the hair follicles but no pigment in the skin, then the light
is much easier to focus on just the follicles to destroy them
without affecting the skin. Treatment involved choosing different
settings for patients considering their individual skin and hair
follicle characteristics. Immediately after treatment, ice packs
were applied on the treated areas. Flammazine cream (Silver Sulfadiazine)
was applied to control any itchy feeling.
The follow-up treatment was carried out 4 to 6 weeks after the
initial treatment. The subsequent treatments were taken up in
due course of time depending on the individual hair-growth characteristics
of each patient.
Outcome of the Study
To the great satisfaction of the researchers, the study produced
favorable and encouraging results. An average of 87% hair reduction
resulted after about 8 sittings. (This is an average summation,
with some patients requiring as few as 2 sittings while others
needed as many as 23 treatments). The whole course of treatment
(along with follow up sessions) ranged between 9 and 74 months.
The study established the vital connection between hair reduction
and the number of IPLS treatments received. In fact, they are
directly proportional, i.e., the more the number of treatment
sessions, the higher the hair reduction. Another revelation in
this respect is that the greater the time intervals between two
subsequent sessions, the more are the chances of inconsistent
The study also recognized the relationship between hair reduction,
hair pigment and hair quality. It was found that the darker the
hair color, the more effective was the IPLS treatment. Actually,
the melanin content in light colored hair is far less compared
to darker hair. Therefore, the light source fails to target enough
chromophore to cause effective hair removal in light colored hair.
Hence, the blond and gray haired patients have to undergo extra
treatment sessions to obtain similar effects as dark haired people
can with fewer sessions.
Another important finding derived from the study is that it is
easier to treat fine hair in relation to coarse hair. The thick
keratin cover of the coarse hair calls for higher energy levels
for effective removal. The pulse-time too plays a vital role in
hair reduction. It was observed that with short pulse times, the
time required to destroy a hair follicle rises, which eventually
causes less hair reduction. Contrarily, longer pulse-times lead
to better hair reduction with fewer treatment sessions.
Apart from the Maastricht Study, quite a few research studies
have been conducted to ascertain the efficacy of IPL in bringing
about satisfactory results in hair removal and long-term hair
reduction. While some of these studies employed first-generation
flashlamps, others were based on second-generation epilights.
The cases might be dissimilar in their approaches as well as in
some of their minor findings – differing with the number
and frequency of treatment sessions, pulse time, energy level,
etc. In essence, however, the outcomes are comparable – the
IPLS technique effects permanent hair removal.
The word ‘permanent’ in this study does not imply
lifelong, rather denotes a considerable reduction in the number
of terminal hairs after being treated with the IPL method, the
effect of which outlasts the complete growth-cycle of the hair
follicle at a particular body site.
Most of the research studies on IPLS highlight the importance
of multiple treatments for satisfactory hair removal. This, because
the human hair follows a mosaic pattern of growth and only multiple
treatments can fully destroy the hair – shaft, bulb, et
The inference that the bulge area in the hair follicle is as
much responsible for the re-growth of hair as the hair follicle
itself has further emphasized the role of IPLS treatment for effective
long-term hair reduction. Complete destruction of the hair follicle
and the bulge requires exposure to a safe amount of energy, which
permits minimal or negligible negative side effects.
Intense pulsed light source (IPLS) treatment for hair removal references
- Schroeter CA, Groenewegen JS, Reineke T, Neumann
HA. Hair reduction using intense pulsed
light source. Dermatol Surg. 2004 Feb;30(2 Pt 1):168-73. PMID: