Red Light Therapy For Cold Sores: Does It Work?

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Cold sores, also known as fever blisters, are a common viral condition caused by the herpes simplex virus (HSV). They can be painful and take weeks to heal. While many home remedies and prescription medications are available, they often provide limited relief or come with unwanted side effects.

However, there is a clinically proven homemade remedy that offers promising results—red light therapy. Red light therapy, also known as photobiomodulation or low-level light therapy (LLLT), has demonstrated healing, skin-regenerating, and anti-inflammatory properties.

In this article, we will explore the effects of red light therapy on cold sores and understand how it can be an effective treatment option.

What is Red Light Therapy?

Red light therapy is a skin treatment that uses low-wavelength infrared light to improve skin conditions like scars, acne, and wrinkles. It’s done with a device that emits light from LEDs. Red light therapy has many names, such as soft laser therapy, low-level light therapy, and photobiomodulation.

The reason red light is used is because it can penetrate the skin effectively. It helps cells, especially mitochondria, which produce energy (ATP), become more efficient. As people age, mitochondria become less efficient, but red light therapy helps them produce more ATP, which provides energy to other cells.

Additionally, red light exposure can stimulate the body to produce antioxidants, which are important for preventing damage and reducing inflammation in the body.

What Causes Cold Sores?

Cold sores are common viral infections caused by herpes simplex viruses, specifically HSV-1 or HSV-2. They spread easily through close contact and, unfortunately, have no cure. However, they typically go away on their own within a few weeks.

To treat cold sores, doctors often prescribe medications. But there are also natural remedies like red light therapy, creams, and less invasive options that can help heal them faster and reduce discomfort.

As for symptoms, cold sores usually start with an itchy, painful spot around your mouth, lips, nose, or cheeks. These small blisters often tingle or burn before they burst.

How Does Red Light Therapy Treat Cold Sores

Research has shown that red light therapy accelerates the healing process and reduces pain associated with oral and labial HSV lesions. Multiple studies have focused on laser and LED treatments using red and near-infrared (NIR) wavelengths ranging from 660nm to 780nm. These studies have consistently demonstrated positive outcomes for patients suffering from cold sores.

In a study involving 69 patients with mouth ulcers, significant improvement was observed after just one treatment using red wavelengths ranging from 650nm to 680nm. Similarly, two patients who refused topical antiviral medicines experienced remission and remained symptom-free during the follow-up period after undergoing red light therapy with 660nm wavelengths.

Furthermore, a long-term study involving 232 patients utilizing 670nm red light therapy showcased a significant extension in the time between cold sore flare-ups. Another study focused on herpes zoster (chickenpox and shingles) found that patients treated with red light therapy remained symptom-free for an average of 37.5 weeks, compared to only three weeks for the control group.

In addition, a study on lip HSV cold sores involving 87 patients showed that infrared wavelengths (1072nm) led to a shorter median healing time compared to the control group treated with a placebo. Moreover, a study with 28 patients suffering from herpes zoster virus-induced cold sores demonstrated faster healing and reduced pain when treated with NIR light (830nm).

Red Light Therapy

Mechanism of Action

Red light therapy promotes biostimulation in human tissue, triggering a photochemical reaction at the cellular level. This therapy stimulates energy production within the mitochondria of cells, the vital organelles responsible for generating cellular energy. By enhancing mitochondrial function, red light therapy helps cells perform their functions effectively, repair damage, and replicate.

Mitochondrial dysfunction is associated with an increased risk of infections due to a weakened immune system. Red light therapy corrects mitochondrial dysfunction, supporting the immune system in maintaining a state of health. Moreover, red light therapy reduces chronic inflammation, which can contribute to mitochondrial dysfunction and make the body more susceptible to viruses.

Benefits of Red Light Therapy for Cold Sores

  1. Reduced Inflammation: Red light therapy has pronounced anti-inflammatory effects, helping alleviate chronic inflammation that can lead to various health issues, including cold sores.
  2. Increased Collagen Production: Red light therapy stimulates collagen production, which is crucial for healthy skin. By promoting collagen density, red light therapy aids in the regeneration of healthy skin after cold sore lesions have healed.
  3. Improved Circulation: Red light therapy supports the formation of capillaries and enhances endothelial cell proliferation, which improves circulation. Proper blood flow is essential for the nourishment of skin cells and aids in the healing process of cold sores.

Is Red Light Therapy Safe?

Yes, red light therapy is safe and preferred by dermatologists because it rarely causes side effects. Unlike UV light treatments, it doesn’t have harmful health effects. However, it’s essential to have a qualified cosmetic specialist guide your treatment for your specific skin issues.

Keep in mind that red light therapy works best for short-term issues like cold sores. To protect your eyes and skin from potential long-term effects, avoid excessive exposure during treatment. While there are no significant known risks when used responsibly, there might be undiscovered long-term effects. So, it’s wise to be cautious and follow professional instructions during red light therapy.

Using Red Light Therapy at Home

Today, powerful LED panels with clinical-grade light output are available for home use. These devices enable individuals to undergo red light therapy treatments in the comfort of their homes.

By using these devices during outbreaks and incorporating regular LED red light treatments into their skincare routine, individuals can prevent cold sores and reduce the frequency of recurring flare-ups.

Moreover, consistent red light therapy sessions provide overall skin health benefits, boost the immune system, and reduce inflammation throughout the body.

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In conclusion, red light therapy is a great way to treat cold sores caused by the herpes simplex virus. It helps heal sores, reduce inflammation, boost collagen production, and improve blood circulation.

You can easily use red light therapy at home with LED devices. This can help you have healthier skin and feel better overall.

So, think about adding red light therapy to your skincare routine to treat cold sores and improve your skin’s health.

Looking for professional skincare advice? Schedule an online consultation with dermatologist Dr. Ava Patel to address your concerns.

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