Red Light Therapy for Psoriasis: A Promising Emerging Approach

We aren't making any claims in this article; We are simply sharing research.

RED LIGHT THERAPY

is emerging as a potential tool for managing psoriasis symptoms. This article explores the scientific evidence around this subject.

PSORIASIS

Can be a challenging condition, and many are seeking effective ways to improve both skin health and overall quality of life.

LET’S SUMMARIZE:

Psoriasis is a chronic inflammatory skin disorder that more commonly affects children than adults. It is primarily driven by an overactive immune response and is associated with an increased risk of comorbid conditions, including cardiovascular disease, joint disorders, diabetes, and various mental health challenges. Globally, approximately 2% of the population is affected, with higher prevalence rates observed in regions farther from the equator.

There are several forms of psoriasis, with plaque psoriasis accounting for 80–90% of cases. Standard treatment approaches typically involve topical medications, and in more severe cases, systemic pharmaceuticals. Light-based therapies have also been used for decades as part of psoriasis management, supported by a long history of clinical application.

Various forms of light therapy have shown encouraging results in the treatment of psoriasis, including ultraviolet (UV), blue, red, and near-infrared light. Blue light has been noted for its ability to reduce redness and scaling, though many studies have shown the use of relatively high intensities and doses. UV light—particularly UVB, which also triggers vitamin D production in the skin—is considered a standard clinical option and is typically administered under the supervision of a dermatologist. If choosing to use UV light, do so at your own risk, and make sure to always seek medical guidance.

Red and near-infrared light within the 600–1000 nm wavelength range have also demonstrated positive effects in managing psoriasis, with some studies utilizing high doses (100–200 J/cm²) and higher-intensity devices. While additional research on red and blue light therapy is still needed, current findings are highly encouraging.

Proper dosing and careful monitoring of skin response are essential to avoid adverse effects such as sunburn or symptom flare-ups. Supporting overall skin health through a balanced

lifestyle—including adequate sleep and nutrition—is also important, particularly when using blue or ultraviolet light as part of a psoriasis treatment plan.

BASIC PSORIASIS KNOWLEDGE

To begin, it’s important to understand what psoriasis is. This section draws on recent scientific reviews that evaluate high-quality research publications on the subject (1; 2; 3; 4; 5; 6; 7; 8; nanoparticles).

BASICS OF PSORIASIS: PATHOLOGY, RISK FACTORS  & BEYOND

Psoriasis is a complex inflammatory disorder that primarily manifests through skin-related symptoms (1). Its development is influenced by a combination of genetic predisposition and environmental risk factors (1). A key contributor to the condition is an overactive immune response, particularly involving imbalances in inflammatory signaling molecules known as cytokines (1).

Individuals with psoriasis also face a heightened risk of developing additional health conditions (1). These may include cardiovascular disease, type II diabetes, metabolic syndrome, various inflammatory disorders such as arthritis, and mental health challenges (1; 2). Notably, the risk of cardiovascular disease alone is elevated by approximately 50% in those with psoriasis (7).

Similar patterns have been observed in related areas of skin health, including studies on red light therapy for eczema. While psoriasis and eczema share certain characteristics, they also differ in key ways. Researchers have explored this connection, noting the following:

"Except for cardiometabolic diseases, gastrointestinal diseases, chronic kidney diseases, malignancy, and infections that have received much attention, the association between psoriasis and more systemic diseases, including the skin system, reproductive system, and oral and ocular systems has also been revealed, and mental health diseases draw more attention not just because of the negative mental and mood influence caused by skin lesions, but a common immune-inflammatory mechanism identified of the two systemic diseases." (3) Psoriasis affects approximately 2% of the global population (1), with higher prevalence observed in regions farther from the equator (10; 11).

This geographic trend is noteworthy, as limited light exposure in these areas—due to weaker sunlight, colder climates, and reduced time spent outdoors—may play a role in the condition’s development. Given that various forms of light, including red, near-infrared, blue, and ultraviolet, have shown potential benefits for psoriasis, this correlation with the distance from the equator warrants particular attention.

For mild cases of psoriasis, topical therapies—including vitamin D-based treatments—are commonly used (2). These approaches typically work by targeting the overactive immune response. In more severe cases, oral medications may also be required (2). However, even with pharmaceutical intervention, symptoms are often not fully controlled.

TYPES OF PSORIASIS

There are multiple forms of psoriasis, and each may require a distinct treatment approach (12; 13):

· Plaque psoriasis is the most common form, affecting 80–90% of individuals with the condition. It is characterized by raised, red patches of skin covered with white scales. Commonly affected areas include the scalp, elbows, knees, and lower back. Because some of these areas are visible, the condition can also lead to aesthetic concerns that impact self-esteem and overall quality of life.

· Guttate psoriasis accounts for approximately 10% of cases and is characterized by small, drop-shaped lesions. It is often triggered by streptococcal infections and typically appears on the trunk, arms, and legs. This form is more commonly seen in younger individuals.

· Inverse psoriasis accounts for approximately 3–7% of cases and is more commonly seen in individuals who are overweight or obese. It typically affects areas such as the underarms and groin, where sweating and friction from movement can worsen symptoms.

· Nail psoriasis impacts up to 50% of individuals with psoriasis and can affect both fingernails and toenails. Common symptoms include pitting, thickening, discoloration, and detachment of the nail from the nail bed.

· Psoriatic arthritis occurs in roughly 30% of psoriasis cases, often developing years after the appearance of skin symptoms. This form is associated with joint inflammation and shares characteristics with traditional arthritis. Additionally, up to 80% of those with psoriatic arthritis also experience nail involvement.

· There are also rare forms of psoriasis, such as erythrodermic psoriasis and pustular psoriasis, which are not covered in detail here. These types can sometimes require urgent medical attention, so it is important to consult a healthcare professional if they are suspected.

These forms of psoriasis can overlap, and the condition is currently considered chronic with no known cure (12). Psoriasis involves an autoimmune component, where the immune system mistakenly targets the body’s own cells. The following section will explore the roles of immune function and inflammation in more detail.

TREATMENT OF PSORIASIS

Systemic inflammation is the primary focus of treatment in this context (4). In the future, approaches may become more personalized based on specific inflammatory biomarkers (4). Researchers have highlighted this promising development as follows:

"Cutting-edge research studies and comprehensive insights into psoriasis pathogenesis, fostering novel genetic, epigenetic, and immunological factors, have generated a spectacular improvement over the past decades, securing the path toward a specific and targeted immunotherapeutic approach and delayed progression to inflammatory arthritis." (5).

These advancements are highly encouraging! Emerging treatments, such as nanoparticle-based therapies, offer the potential for effective topical application with reduced side effects (8). Early intervention and ongoing symptom management are important, as psoriasis-related complications often progress over time (9). Beyond skin involvement, the condition may extend to the joints, eyes, gastrointestinal system, metabolism, and cardiovascular health (9).

Before exploring the specific role of red light therapy in psoriasis management, it's helpful to first consider its broader benefits for skin health and appearance.

HOW DO RED AND NEAR-INFRARED LIGHT INFLUENCE SKIN HEALTH?

Red light therapy shows significant potential for supporting overall skin health, with applications ranging from cosmetic enhancement to anti-aging and the management of certain skin conditions. In the realm of aesthetics, it has been associated with reductions in wrinkles, improved collagen production and skin elasticity, enhanced hydration, and both prevention and repair of sun-related damage. Due to its effectiveness, red light therapy has seen a surge in popularity.

The most well-supported wavelengths for promoting skin appearance fall within the 620–670 nm range. Effective dosing typically ranges between 3 and 15 J/cm², as reported in numerous studies. In some cases, additional wavelengths—such as amber or blue light—may also be beneficial (32, 33, 34, 35).

In general, more high-quality research is needed to fully establish the effectiveness of red light therapy for cosmetic purposes. While most outcomes are positive, a small number of users have

reported side effects, such as increased facial hair growth or pigmentation changes related to overuse. These will be discussed further shortly.

Importantly, red light therapy also shows promise in addressing various skin conditions, including acne, eczema, rosacea, wound healing, and sun damage (27, 28, 29, 30, 31). The outlook for light-based therapies in dermatology continues to be highly promising.

HOW DO RED AND NEAR-INFRARED LIGHT IMACT PSORIASIS?

Now let’s review some of the more interesting light therapy studies on Psoriasis. Below are four studies and two reviews on the topic.

VISIBLE LIGHT STUDIES

To start, let’s explore the four individual studies that were all performed on humans:

· First, a study utilizing 633 nm and 830 nm wavelengths was conducted on nine human participants with chronic psoriasis (15). High doses of 126 J/cm² and 60 J/cm² were applied. The protocol involved two treatment sessions per day, spaced 48 hours apart, over a period of 4 to 5 weeks. The results were remarkably significant:

"Follow-up periods were from 3 to 8 months, except in two patients who were lost to follow-up. Clearance rates at the end of the follow-up period ranged from 60% to 100%. Satisfaction was universally very high." (15).

· The results of this study are highly encouraging. However, it is important to note that it was not a randomized, placebo-controlled trial (RCT), but rather a series of nine case studies. Replication of this protocol in an RCT setting would be valuable. Notably, the use of LEDs makes the treatment approach highly reproducible. · The second study compared the effects of 420 nm blue light and 630 nm red light (16). Blue light was delivered at 100 mW/cm² and red light at 50 mW/cm². Each treatment session lasted 20 minutes, with a total of 20 sessions administered. The cumulative dose was 120 J/cm² for blue light and 60 J/cm² for red light. The two light sources were directly compared, with the following compelling outcome:

"Clinical improvement was seen after treatment with blue as well as after treatment with red light. With respect to scaling and induration, no major differences between both light sources were seen. Improvement of erythema, however, continued in blue light irradiated plaques throughout the whole study period, whereas after red light no significant improvement was seen after six illuminations." (16).

· Once again, the results are very promising and demonstrate strong potential.

· A third study investigated the use of 453 nm blue light over a 12-week period, with a total of 44 to 52 treatment sessions—approximately 3 to 4 sessions per week (17). Two power levels were tested: 100 mW/cm² and 200 mW/cm², both relatively high intensities. The group receiving the higher-powered treatment experienced greater improvements in their psoriasis symptoms.

· The fourth study examined the use of red and near-infrared light in the 600–1,000 nm range for psoriasis treatment (18). This was a case study, and only three of the five participants completed the full protocol. The reported outcome is as follows:

"The three patients who completed the study noted improvement and two had improvements in lesion redness, thickness, or scale, while one was clinically stable. "(18).

· Although the psoriasis cases were mild, the treatment still resulted in noticeable improvements.

Overall, the results of these studies are highly positive, supporting the view that red light therapy—especially when combined with blue light—holds strong potential as a transformative approach in psoriasis management.

Review Studies on Psoriasis Two reviews have been published on the use of red light therapy for psoriasis (19; 20). These reviews are somewhat more cautious in their conclusions, likely due to the limited number of high-quality studies available. Systematic reviews typically require a larger body of evidence—often at least 5 to 10 randomized controlled trials (RCTs)—and thus, the promising case studies discussed earlier are not weighed as heavily.

THE FINDINGS OF THE FIRST REVIEW ARE AS FOLLOWS:

"5 original articles met inclusion criteria for our review. Grade of recommendation: B for LED-blue light. Grade of recommendation: C for LED-ultraviolet B, LED-red light, and combination LED-near-infrared and LED-red light." (19)

There is solid evidence supporting the use of blue light, along with emerging evidence for red, near-infrared, and even ultraviolet light. Now let’s look at the findings from the second review:

"Based on the efficacy and safety, NB-UVB represents the gold standard for treating psoriasis and atopic dermatitis. The UVB excimer laser and excimer lamp might be the best option for clearing localized therapy-resistant lesions. Home UV phototherapy systems might promote

treatment adherence and better compliance of the patients. Vascular lasers, IPLs and LLLT, however, cannot currently be recommended for the treatment of inflammatory skin diseases because of the lack of well-controlled studies." (20).

UV LIGHT THERAPY FOR PSORIASIS: WHAT TO KNOW.

Numerous reviews have been published on the use of ultraviolet light for psoriasis. However, the majority of these reviews are over a decade old, and surprisingly, few recent analyses are available (21; 22; 23; 24; 25; 26).

Despite this, it is still valuable to examine the findings from these earlier reviews. The outcome of the first review is as follows:

"As a monotherapy, [Psoralen - a plant-based skin treatment and UVA] was more effective than [Narrow-Band]-UVB, and [Narrow-Band]-UVB was more effective than [Broad-Band]-UVB and bath [Psoralen - a plant-based skin treatment and UVA] in the treatment of adults with moderate to severe plaque-type psoriasis, based on clearance as an end point" (21)

UVA as well as Psoralen were found to be the most effective approach, followed by lower-wavelength UVB treatments. This review included data from 41 earlier randomized controlled trials. The second review also reported positive outcomes related to UV exposure (22). Some studies utilized broad UVB treatment, while others employed excimer lasers:

"In a non-excimer light study, high doses cleared the most plaques. The 308-nm excimer laser had long-term clearance in 13 of 26 patients. The mean number of UVB treatments in all 9 studies and highest cumulative dose was less than those same parameters in nontargeted phototherapies. Common adverse effects included erythema, blisters, hyperpigmentation, erosion, mild burning, and itching. The predominant setting for excimer units is the office; however, the majority of no excimer light devices can also be used at home. Targeted phototherapy should be considered among the treatment options for localized variants of psoriasis." (22)

Then there’s the third review about UVB treatment, it states:

"NB-UVB and excimer laser are effective treatment options for psoriasis; they are administered two to three times weekly until clearance followed by maintenance treatment before discontinuation. Long-term data on NB-UVB indicate that it has a good safety profile" (23)

The fourth review supports this conclusion, recommending three weekly treatments over a three-month period for plaque-type psoriasis, which accounts for 80–90% of all cases (24).

Additionally, a 2023 review identified UVB therapy as likely the most cost-effective treatment option (25).

Another, more recent review examined the combined use of saltwater baths and UVB therapy (26), incorporating data from eight previous studies. The outcome of that review is as follows:

"Salt bath with artificial ultraviolet B (UVB) light may improve psoriasis in people with chronic plaque psoriasis compared with UVB light treatment alone, and there may be no difference in the occurrence of treatment-related adverse events requiring withdrawal. Both results are based on data from a limited number of studies, which provided low-certainty evidence, so we cannot draw any clear conclusions. The reporting of our pre-specified outcomes was either non-existent or limited, with a maximum of two studies reporting a given outcome. [...] Risk of bias was an issue; future studies should ensure blinding of outcome assessors and full reporting." (26)

Once again, the quality of the available evidence is not without limitations. In clinical research, medical scientists typically apply much stricter standards, often requiring multiple large-scale randomized controlled trials to support a treatment’s effectiveness. However, conducting such studies can be prohibitively expensive—particularly for non-patentable therapies like UVB light—resulting in a persistent gap in large-scale evidence.

That said, the existing data is sufficient to support the use of UVB therapy, with or without salt baths, particularly for plaque psoriasis. Additionally, current evidence provides a strong basis for recommending both red and blue light therapy as viable options.

RED LIGHT THERAPY: POTENTIAL ADVERSE EFFECTS AND CONSIDERATIONS

There are indeed some potential side effects associated with red light therapy for psoriasis. While it’s possible to address your condition using light therapy at home, it is particularly important in the context of psoriasis to monitor your response closely and seek guidance from a healthcare professional.

For those considering ultraviolet (UV) light therapy, it is strongly recommended to consult with a physician or dermatologist beforehand. Any use of the products mentioned earlier should be done at your own discretion and risk.

Excessive use of blue or ultraviolet light can lead to side effects—this is not speculative but well-documented in scientific literature. Melasma and hyperpigmentation are examples of this (36, 37).

In general, blue, red, and near-infrared light appear to be safer options for facial use when applied at standard power levels, typically between 40–100 mW/cm². However, direct ultraviolet light exposure to the face is not advisable due to the increased risk of overexposure. For those seeking UV benefits for facial skin, moderate sun exposure—while avoiding sunburn—is a safer alternative.

While it falls outside the main focus of this article, it's important to note that the skin’s protective mechanisms must function properly for optimal results. Adequate sleep and proper nutrition are essential to support these processes.

IN CONCLUSION:

Red Light Therapy—A Promising Option for Psoriasis Relief

Red light therapy appears to be a strong fit for managing psoriasis. Based on the wide range of studies reviewed, incorporating blue and ultraviolet light may further enhance treatment outcomes.

That said, several uncertainties remain in the current body of research. For example, there are no published studies directly examining the combined use of red, blue, and ultraviolet light for psoriasis. However, since these light types naturally occur together, their combined use is not a major concern from a theoretical standpoint.

The most challenging aspect is determining proper dosing—especially for blue light, which may require higher levels than those used in some studies. Balancing effective doses of ultraviolet, red, and near-infrared light is also essential.

At present, the safest approach may be to receive ultraviolet light treatments under the supervision of a dermatologist, while managing red and near-infrared light therapy at home.

The outlook for individuals with psoriasis is promising with light-based therapies leading the way. Embracing these innovations may offer new hope in symptom management.