Low level laser therapy (LLLT) is a non-invasive, non-pharmacological Treatment for androgenetic alopecia (AGA) in both men and women. The ‘laser’ in Lllt is actually red light, which is emitted from diodes in a LLLT device. Devices can be helmets or caps that patients place on their head or, there are combs that emit red light that patients can manually use through their Hair. LLLT devices are available for home-use without a prescription, either from physicians’ offices or from direct sales websites. However, men and women do not have to commit to purchasing a portable home device. There are larger, non-portable devices that can be used multiple times a week while visiting a clinic.

Red light is the ideal wavelength to stimulate growth and it is thought that light acts on a number of different processes in hair cells, including increasing the release of growth factors.^[1,2] It is important to point out that hair follicles need to be present in order for light to stimulate them. If hair loss has progressed to the point where there are no follicles in an area of the scalp, then there will be nothing to stimulate. LLLT stimulates the hair that is present to help prevent further hair loss and potentially increase hair density and thickness. This means that the earlier a person with thinning hair is able to try LLLT, the greater the chance that favorable results will occur. If a person has been bald in an area of the scalp for quite some time, then LLLT may not be an appropriate treatment.

Successful treatment with LLLT has been demonstrated in 3 recent studies.^[3–5] Two recent clinical trials investigated the use of a bicycle helmet-like device available for personal use at home (iGrow® helmet, Apira Science).^[3,4] Treatment occurred for 25 minutes, every other day for 16 weeks, totaling 60 treatments. While the helmet device served as the treatment group, those assigned to the control group used an identical helmet, but with incandescent red lights. Therefore, no treatment was applied to the scalp. Both the patients and the doctor evaluating treatments did not know which device (LLLT or control red light) a person had used (double-blind trial).

Forty one men completed the first clinical trial,^[3] while 42 women completed the second clinical trial.^[4] Pictures of the scalp were taken before treatment and after treatment, with the area of interest being the vertex area of the head where hair loss was occurring. At the end of treatment (16 weeks), LLLT resulted in increases in hair counts in both men and women. LLLT produced an increase in hair counts of 35% and 37% as compared to the control treatment, for men and women respectively. The density of hair in the area of interest also increased. In men and women, LLLT resulted in an average increase of 30.4 hairs/cm² and 35.2 hairs/cm², while men in the control group saw an average decrease of -0.11 hairs/cm² and women in the control group an average increase of 8.39 hairs/cm². There were no adverse side effects reported with use of this helmet device. Treatment success was measured after 4 months of device use; most studies measure effectiveness after 6 months.

The second device investigated in clinical studies is the HairMax Lasercomb® (Lexington International).^[5,6] A large-scale, double-blind study tested the performance of multiple models of the comb device in 122 women and 103 men.^[5] The comb device was used at home, three times per week, for 8-15 min, depending on the model of comb. Combs differed in how many beams of lights they contained. While the LLLT comb emitted red light, the control device emitted white light. Devices were used for 26 weeks (6 months). Pictures of the scalp were taken before treatment, and after 16 and 26 weeks of treatment.

After 26 weeks of treatment, women who used a 9-beam or a 12-beam comb showed a significant increase in hair density in the area of interest as compared to women who used a sham (control) comb. Hair density was 20.2 hairs/cm² for the 9-beam comb vs. 2.8 hairs/cm² for the control comb, and 20.6 hairs/cm² for the 12-beam comb vs. 3.0 hairs/cm² for the 12-beam comb. The same pattern was observed in men, with hair density using the 7-beam (18.4 hairs/cm²), 9-beam (20.9 hairs/cm²), or 12-beam comb (25.7 hairs/cm²) significantly greater than the control combs. Furthermore, patient satisfaction was reported. Women using the 9-beam comb reported overall improvement significantly greater than women using a control comb did. Men using a Lasercomb of any model and women using the 9-beam comb also reported noticeable improvements in the thickness/fullness of their hair.^[5]

It should be noted that LLLT is also used in a variety of other situations. For example, red light may help heal skin ulcers and reduce inflammation.^[7] It is used by physiotherapists and chiropractors to assist with soft tissue injuries and decrease inflammation.

In order to see hair growth with a LLLT device, regular use is required. Published studies and clinics suggest using a LLLT device for 20-30 minutes, 3 times a week.^[3–6,8] Depending on the individual, it may take up to 6 months before one can determine whether LLLT is effective in improving hair appearance. Options include visiting a hair restoration clinic to use in-office LLLT devices, or purchasing a device for at-home use. People with androgenetic alopecia pursuing LLLT should choose whichever option would ensure consistent, long-term use.  This non-invasive method is gaining widespread adoption and we use it regularly not only to help maintain but also induce hair growth. Additionally, use after a hair transplant may help reduce shock loss and induce growth of transplanted hair earlier than would have occurred otherwise.

References

1. Keene SA. The science of light biostimulation and low level laser therapy (LLLT). Hair Transpl Forum Int 2014;24(6):201,208-9.
2. Sutherland JC. Biological effects of polychromatic light. Photochem Photobiol 2002;76(2):164–70.
3. Lanzafame RJ, Blanche RR, Bodian AB, Chiacchierini RP, Fernandez-Obregon A, Kazmirek ER. The growth of human scalp hair mediated by visible red light laser and LED sources in males. Lasers Surg Med 2013;45(8):487–95.
4. Lanzafame RJ, Blanche RR, Chiacchierini RP, Kazmirek ER, Sklar JA. The growth of human scalp hair in females using visible red light laser and LED sources. Lasers Surg Med 2014;46(8):601–7.
5. Jimenez JJ, Wikramanayake TC, Bergfeld W, Hordinsky M, Hickman JG, Hamblin MR, et al. Efficacy and Safety of a Low-level Laser Device in the Treatment of Male and Female Pattern Hair Loss: A Multicenter, Randomized, Sham Device-controlled, Double-blind Study. Am J Clin Dermatol 2014;15:115–27.
6. Leavitt M, Charles G, Heyman E, Michaels D. HairMax LaserComb® Laser Phototherapy Device in the Treatment of Male Androgenetic Alopecia: A Randomized, Double-Blind, Sham Device-Controlled, Multicentre Trial. Clin Drug Investig 2009;29(5):283–92.
7. Chaves ME de A, Araújo AR de, Piancastelli ACC, Pinotti M. Effects of low-power light therapy on wound healing: LASER x LED. An Bras Dermatol 2014;89(4):616–23.
8. Gupta AK, Daigle D. The use of low-level light therapy in the treatment of androgenetic alopecia and female pattern hair loss. J Dermatol Treat 2014;25(2):162–3.