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Low level laser therapy and hair regrowth: an evidence-based review

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Abstract

Despite the current treatment options for different types of alopecia, there is a need for more effective management options. Recently, low-level laser therapy (LLLT) was evaluated for stimulating hair growth. Here, we reviewed the current evidence on the LLLT effects with an evidence-based approach, focusing more on randomized controlled studies by critically evaluating them. In order to investigate whether in individuals presenting with hair loss (male pattern hair loss (MPHL), female pattern hair loss (FPHL), alopecia areata (AA), and chemotherapy-induced alopecia (CIA)) LLLT is effective for hair regrowth, several databases including PubMed, Google Scholar, Medline, Embase, and Cochrane Database were searched using the following keywords: Alopecia, Hair loss, Hair growth, Low level laser therapy, Low level light therapy, Low energy laser irradiation, and Photobiomodulation. From the searches, 21 relevant studies were summarized in this review including 2 in vitro, 7 animal, and 12 clinical studies. Among clinical studies, only five were randomized controlled trials (RCTs), which evaluated LLLT effect on male and female pattern hair loss. The RCTs were critically appraised using the created checklist according to the Critical Appraisal for Therapy Articles Worksheet created by the Center of Evidence-Based Medicine, Oxford. The results demonstrated that all the performed RCTs have moderate to high quality of evidence. However, only one out of five studies performed intention-to-treat analysis, and only another study reported the method of randomization and subsequent concealment of allocation clearly; all other studies did not include this very important information in their reports. None of these studies reported the treatment effect of factors such as number needed to treat. Based on this review on all the available evidence about effect of LLLT in alopecia, we found that the FDA-cleared LLLT devices are both safe and effective in patients with MPHL and FPHL who did not respond or were not tolerant to standard treatments. Future randomized controlled trials of LLLT are strongly encouraged to be conducted and reported according to the Consolidated Standards of Reporting Trials (CONSORT) statement to facilitate analysis and comparison.
REVIEW ARTICLE
Low level laser therapy and hair regrowth:
an evidence-based review
Mina Zarei
1
&Tongyu C. Wikramanayake
1
&Leyre Falto-Aizpurua
1
&
Lawrence A. Schachner
1
&Joaquin J. Jimenez
1
Received: 23 February 2015 /Accepted: 12 October 2015 /Published online: 21 December 2015
#Springer-Verlag London 2015
Abstract Despite the current treatment options for different
types of alopecia, there is a need for more effective management
options. Recently, low-level laser therapy (LLLT) was evaluated
for stimulating hair growth. Here, we reviewed the current evi-
dence on the LLLT effects with an evidence-based approach,
focusing more on randomized controlled studies by critically
evaluating them. In order to investigate whether in individuals
presenting with hair loss (male pattern hair loss (MPHL), female
pattern hair loss (FPHL), alopecia areata (AA), and
chemotherapy-induced alopecia (CIA)) LLLT is effective for
hair regrowth, several databases including PubMed, Google
Scholar, Medline, Embase, and Cochrane Database were
searched using the following keywords: Alopecia, Hair loss,
Hair growth, Low level laser therapy, Low level light therapy,
Low energy laser irradiation, and Photobiomodulation. From
the searches, 21 relevant studies were summarized in this review
including 2 in vitro, 7 animal, and 12 clinical studies. Among
clinical studies, only five were randomized controlled trials
(RCTs), which evaluated LLLT effect on male and female pat-
tern hair loss. The RCTs were critically appraised using the
created checklist according to the Critical Appraisal for Therapy
Articles Worksheet created by the Center of Evidence-Based
Medicine, Oxford. The results demonstrated that all the per-
formed RCTs have moderate to high quality of evidence. How-
ever, only one out of five studies performed intention-to-treat
analysis, and only another study reported the method of random-
ization and subsequent concealment of allocation clearly; all
other studies did not include this very important information in
their reports. None of these studies reported the treatment effect
of factors such as number needed to treat. Based on this review
on all the available evidence about effect of LLLT in alopecia,
we found that the FDA-cleared LLLT devices are both safe and
effective in patients with MPHL and FPHL who did not respond
or were not tolerant to standard treatments. Future randomized
controlled trials of LLLT are strongly encouraged to be conduct-
ed and reported according to the Consolidated Standards of
Reporting Trials (CONSORT) statement to facilitate analysis
and comparison.
Keywords Low-level laser therapy .Hair regrowth .
Evidence-based medicine
Introduction
LLLT and paradoxical hypertrichosis
Low-level laser therapy (LLLT) was discovered in the 1960s
and first used by the National Aeronautics and Space Admin-
istration (NASA) to accelerate wound healing in space [1].
Since then, LLLT devices have been used to induce a variety
of therapeutic effects associated with a range of wavelengths,
from red to infrared. The reported biological effects of low-
energy laser include anti-inflammation, pain reduction, wound
healing, anti-edema, antibiosis, immunity, and local blood cir-
culation improvement which are collectively called
biomodulation effect [24]. LLLT is also known as low light
laser therapy, red light therapy, cold laser, and soft laser [1].
One of the traditional uses of laser in dermatology is for
hair removal. Lasers induce this effect by targeting melanin,
which acts as a chromophore. Melanin dissipated the absorbed
*Joaquin J. Jimenez
jjimenez@med.miami.edu
1
Department of Dermatology and Cutaneous Surgery, University of
Miami Miller School of Medicine, 1600 NW 10th Ave., RMSB
2023, Miami, FL 33136, USA
Lasers Med Sci (2016) 31:363371
DOI 10.1007/s10103-015-1818-2
Content courtesy of Springer Nature, terms of use apply. Rights reserved.
... Low-level laser light (coherent light) or light-emitting diodes (LEDs; noncoherent light) act by photomodulation (PBN) therapy on biological tissues, leading to the modulation of cellular functions and tissue regeneration [11]. Low-level laser therapy (LLLT) was evaluated for stimulating hair growth via photobiomodulation [12]. While excimer light 6 Dermatologic Terapy has cutaneous immunomodulation and can prompt T-cell apoptosis, making it a potential and hopeful method for the treatment of alopecia areata [12]. ...
... Low-level laser therapy (LLLT) was evaluated for stimulating hair growth via photobiomodulation [12]. While excimer light 6 Dermatologic Terapy has cutaneous immunomodulation and can prompt T-cell apoptosis, making it a potential and hopeful method for the treatment of alopecia areata [12]. Although the phototherapeutic mechanism of action of excimer light in terms of AA treatment remains unclear, this is thought to be similar to that in play when psoriasis, vitiligo, and atopic dermatitis are treated; the cutaneous immunosuppression by UVB would be the principal mechanism of action. ...
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Background. Alopecia areata (AA) is a nonscarring alopecia that can affect any hairy area of the body. Excimer light at 308 nm with immunosuppressive effects is recommended as a promising management method for AA. Objectives. To assess the efficacy and safety of excimer light at 308 nm alone versus a combination of tacrolimus 0.1% and excimer light in the treatment of alopecia areata. Methods. Forty patients with AA of the scalp were divided into two groups, group A was treated with an excimer lamp twice per week for three months, and group B was treated with a combination of tacrolimus 0.1% and an excimer light. The efficacy of the treatment was evaluated by the SALT score and serum T-regulatory cells at the baseline, after 3 months from the baseline, and after 6 months from the beginning of treatment. Results. In group (A), the median SALT decreased from the baseline (13.15) to (6.15) 3 months after the baseline and further decreased after 6 months of follow-up to (3.3). While in group (B), the median SALT score was decreased from the baseline (11.15) to (0.5) after 6 months from the beginning of treatment. After 3 months, there was improvement in Treg function in both groups A and B (4.98 ± 1.02, 5.50 ± 0.84), respectively. There was a significantly higher improvement in group B (85.19 ± 8.55) than group A (70.05 ± 9.95). Dermoscopic findings reveal decreased signs of activity in group B more than group A. Conclusion. The combination of excimer light and tacrolimus is more effective than excimer light alone in treatment of AA.
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... Stimulates anagen in HFs PGF2a and analogs Enhance the change from telogen to anagen hair [32]. The common side effects such as itching, red spots, congestion in the deep external auditory canal wall, and mild allergic manifestation Low-Level Laser Therapy in Patients with Complaints of Tinnitus: A Clinical Study. ...
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Background: Androgenetic alopecia (AGA) is the most common form of hair loss in men and in women. Currently, minoxidil and finasteride are the treatments with the highest levels of medical evidence, but patients who exhibit intolerance or poor response to these treatments are in need of additional treatment modalities. Objective: The aim was to evaluate the efficacy and safety of low-level laser therapy (LLLT) for AGA, either as monotherapy or as concomitant therapy with minoxidil or finasteride, in an office-based setting. Materials and methods: Retrospective observational study of male and female patients with AGA, treated with the 655 nm-HairMax Laser Comb(®), in an office-based setting. Efficacy was assessed with global photographic imaging. Results: Of 32 patients (21 female, 11 male), 8 showed significant, 20 moderate, and 4 no improvement. Improvement was seen both with monotherapy and with concomitant therapy. Improvement was observed as early as 3 months and was sustained up to a maximum observation time of 24 months. No adverse reactions were reported. Conclusions: LLLT represents a potentially effective treatment for both male and female AGA, either as monotherapy or concomitant therapy. Combination treatments with minoxidil, finasteride, and LLLT may act synergistic to enhance hair growth.