What is the effect of low-level laser therapy (LLLT) or photobiomodulation (PBM) using red light?

From the Guidelines

Red light therapy, specifically low-level laser therapy (LLLT) or photobiomodulation (PBM), has been shown to be effective in improving skin health, reducing inflammation, and promoting healing, particularly for conditions like actinic keratosis (AK). The most recent and highest quality study, published in 2021 1, conditionally recommends the use of ALA-red light PDT for the treatment of AK, with longer application times (1 hour to 4 hours) favored to enhance complete clearance of AKs. However, it's essential to note that ALA-daylight PDT is also recommended as a less painful and equally effective alternative to ALA-red light PDT.

Key Findings

• The study found that the incidence of local skin treatment with ALA-red light PDT over 35% TCA peel reactions during illumination was dose-dependent and ranged from 26% in the 0.5-hour group to 66% in the 4-hour group 1.
• The efficacy and safety of ALA-red light PDT were compared to those of chemical peeling using 35% trichloroacetic acid for treatment of AKs on the head, with PDT treatment found to be superior for lesion reduction and rates of complete clearance 1.
• The use of longer ALA application times (1 hour to 4 hours) over shorter application times was favored to enhance complete clearance of AKs, based on low-quality evidence 1.

Recommendations

• Consider red light therapy for conditions like mild to moderate acne, wound healing, and reducing signs of aging, but it should not replace conventional medical treatments for serious conditions.
• Typical treatment involves sessions of 10-20 minutes, 3-5 times per week, using devices that emit red light in the 630-660nm range or near-infrared light in the 810-850nm range.
• For home use, FDA-cleared devices are available ranging from $30 for small handheld units to $300+ for larger panels.
• The therapy works by stimulating mitochondria in your cells, potentially increasing energy production and reducing oxidative stress, which can lead to increased collagen production, improved circulation, and reduced inflammation.

Safety and Side Effects

• Results typically take 8-12 weeks of consistent use, and the therapy is generally considered safe with minimal side effects, though people with photosensitivity disorders or taking certain medications should consult a healthcare provider first 1.
• Postinflammatory hypopigmentation or hyperpigmentation can occur following PDT, and hair loss is a potential side-effect of PDT as concomitant sensitization of the pilosebaceous unit takes place 1.

From the Research

Effects of Low-Level Laser Therapy (LLLT) or Photobiomodulation (PBM) using Red Light

• LLLT using red and near-infrared wavelengths has been shown to promote wound healing, reduce inflammation and pain, and restore function 2, 3, 4, 5.
• The mechanism of action involves the absorption of photons by mitochondrial chromophores in skin cells, leading to increased electron transport, adenosine triphosphate production, and nitric oxide release 3, 5.
• Red and near-infrared wavelengths have been found to be effective in promoting wound healing, with 635 nm and 810 nm being the most effective wavelengths 4.
• LLLT has also been shown to have beneficial effects on various skin conditions, including wrinkles, acne scars, hypertrophic scars, and pigmentary disorders such as vitiligo 3.
• The use of different wavelengths, including blue light, has also been explored, with promising results in improving wound healing and angiogenesis 6.

Wavelength-Specific Effects

• Red light (630-680 nm) has been shown to have beneficial effects on wound healing, inflammation, and pain reduction 2, 4.
• Near-infrared light (800-830 nm) has been found to be the most effective wavelength range for promoting wound healing and tissue repair 2, 4.
• The effectiveness of different wavelengths may depend on the specific condition being treated, with some wavelengths being more effective than others for certain applications 4, 6.

Therapeutic Applications

• LLLT using red and near-infrared wavelengths has been explored as a potential treatment for various conditions, including chronic wounds, skin disorders, and inflammatory diseases 2, 3, 5.
• The non-invasive nature and lack of side effects make LLLT an attractive option for the treatment of various conditions, with further research needed to fully explore its therapeutic potential 3, 5.