Red Light Phototherapy

Red Light Phototherapy is a treatment that involves exposing the skin to high intensity red light in the red spectrum. The purpose of the treatment is to reduce skin inflammation and accelerate healing.

Red Light Phototherapy and Acne

Red Light Phototherapy is primarily used as a treatment for minor acne-scarring and to facilitate healing after an acne outbreak. It is also occasionally used for the treatment of active acne symptoms.

Red Light Phototherapy is most commonly used for the treatment of acne scars. It does not appear to be an effective scar treatment by itself, but it can be combined with other types of scar treatments (eg. Laser Resurfacing, Microdermabrasion) to accelerate the healing process.

Results from several clinical research studies indicate that Red Light Phototherapy can be partially effective as a treatment for active acne symptoms. However, the improvement in active acne symptoms in response to Red Light Phototherapy is likely to incomplete and temporary. For example, one study that evaluated Red Light Phototherapy found that treatment caused a small decrease in inflammation, but did not reduce the levels of acne-causing P. acnes bacteria or the production of sebum by sebaceous glands. This indicates that Red Light Phototherapy may be helpful by decreasing inflammation, but does not address some of the more fundamental causes of acne.

How Does Red Light Phototherapy Work?

Red Light Phototherapy is most commonly used for photo-rejuvenation procedures. Several research studies have reported that red light (600-900 nm) stimulates the growth of new skin tissue and the production of collagen. However, the underlying science of many of these studies is questionable.

High intensity Red Light Phototherapy also appears to assist in the resolution of inflammation, redness and other types of uneven skin tone. Scientists have some ideas about how red light might cause these changes in skin tissue, but the exact mechanism (or mechanisms) are not well understood. Nonetheless, the results from clinical research studies of Red Light Phototherapy have been generally positive. Although these study results may overstate the benefit of Red Light Phototherapy, the treatment is becoming more popular.

Researchers of Red Light Phototherapy have reported that the treatment induces the production and remodeling of collagen and elastin fibers. Collagen and elastin are protein based fibers that form an interconnected matrix (Extra-Cellular Matrix, ECM) that provides structural support and elasticity to the skin. A healthy ECM is one where the fibers form a three dimensional, interconnected structure that is capable of stretching and compressing in all directions. When skin is damaged or ages, the density and organization of the collagen and elastin matrix tends to deteriorate. Increasing the production of healthy collagen and elastin in the skin is one of the primary goals in skin rejuvenation procedures.

Researchers have also reported that specific wavelengths of light in the red spectrum appear to stimulate certain cellular functions. Some specific cellular components, mainly enzymes, have been shown to absorb light in the red spectrum. The most well studied of these red light absorbing enzymes is cytochrome c oxidase, an essential component of mitochondria, which are the power sources of a cell. The absorption of photons (light) by cytochrome c oxidase apparently increases the metabolic activity in a cell, which may explain the accelerated rate of healing observed after Red Light Phototherapy.

How is Red Light Phototherapy Administered?

Most Red Light Phototherapy procedures use large panels of LED lights to create a high intensity source of a specific color (wavelength) of red light. Depending on the treatment, the precise wavelength of the light used can range from 600 nm (orange/red) to 850 nm (infra-red). Achieving therapeutic benefits from Red Light Phototherapy appears to require a very high intensity light source.

Home use Red Light Phototherapy systems are available for purchase on the internet. Home-use phototherapy systems range between $20 and $700 dollars, with large variations in the size, intensity and quality of the various systems. Small and inexpensive home-use phototherapy systems are unlikely to be capable of generating the intensity of light that is required for the therapeutic benefits reported in the clinical research studies.


Influence of 5-Aminolevulinic Acid and Red Light on Collagen Metabolism of Human Dermal Fibroblasts. Karrer, et al. 2003.
cDNA MicroarrayAnalysis of Gene Expression Profiles in Human Fibroblast Cells Irradiated with Red Light. Zhang, et al. 2003.
Clinical Trial of a Novel Non-Thermal LED Array for Reversal of Photoaging: Clinical, Histologic, and Surface Profilometric Results. Weiss, et al. 2005.
Effect of NASA Light-Emitting Diode Irradiation on Wound Healing. Whelan, et al. 2001.
Single Low-dose Red Light is as Efficacious as Methylaminolevulinate Photodynamic Therapy for Treatment of Acne: Clinical Assessment and Fluorescence Monitoring. Horfelt, et al. 2009.
A prospective, randomized, placebo-controlled, double-blinded, and split-face clinical study on LED phototherapy for skin rejuvenation: Clinical, profilometric, histologic, ultrastructural, and biochemical evaluations and comparison of three different treatment settings. Lee, et al. 2007.
Phototherapy with blue (415 nm) and red (660 nm) light in the treatment of acne vulgaris. Papageorgiou, et al. 2000.
Non-invasive diagnostic evaluation of phototherapeutic effects of red light phototherapy of acne vulgaris. Zane, et al. 2008.
Red Light Phototherapy Alone Is Effective for Acne Vulgaris: Randomized, Single-Blinded Clinical Trial. Na, et al. 2007.

Red Light Phototherapy Images