What is low-level laser therapy (LLLT)?

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From the Guidelines

Cold laser technology, also known as low-level laser therapy (LLLT) or photobiomodulation, is a non-invasive medical treatment that uses low-intensity lasers or light-emitting diodes (LEDs) to stimulate healing and reduce pain.

Definition and Mechanism

These devices emit light at specific wavelengths, typically between 600-1000 nanometers, which penetrates the skin without generating heat or causing tissue damage. The light energy is absorbed by cellular components, particularly mitochondria, triggering biochemical changes that enhance cellular function and promote healing.

Clinical Applications

Cold laser therapy is used to treat various conditions including musculoskeletal pain, arthritis, tendonitis, wound healing, and inflammation.

Treatment Parameters

Treatment sessions usually last 5-20 minutes, with patients typically requiring multiple sessions over several weeks for optimal results.

Therapeutic Effects

The therapy works by increasing ATP production in cells, improving blood circulation, reducing inflammation, and accelerating tissue repair.

Safety Considerations

Unlike surgical lasers, cold lasers don't cut or burn tissue, making them safe with minimal side effects, though they should be avoided near cancerous tissues, over the thyroid, or during pregnancy, as noted in studies such as 1.

Evidence-Based Recommendations

According to the most recent and highest quality study, low-level laser therapy is recommended to prevent oral mucositis in patients receiving high-dose chemotherapy and total body irradiation, followed by autologous stem cell transplantation, for a hematological malignancy 1.

Key Points

  • Cold laser technology is a non-invasive medical treatment
  • It uses low-intensity lasers or LEDs to stimulate healing and reduce pain
  • It is used to treat various conditions, including musculoskeletal pain and inflammation
  • Treatment sessions are typically short, with multiple sessions required for optimal results
  • The therapy is safe, with minimal side effects, but should be avoided in certain situations, such as near cancerous tissues or during pregnancy.

From the Research

Definition of Cold Laser Technology

  • Cold laser technology, also known as low-level laser therapy (LLLT), is a form of light therapy that triggers biochemical changes within cells 2.
  • It uses low-frequency continuous laser of typically 600 to 1000 nm wavelength for pain reduction and healing stimulation 2.

Mechanism of Action

  • Photons are absorbed by cellular photoreceptors, triggering chemical alterations and potential biochemical benefits to the human body 2.
  • The photons are absorbed by mitochondrial chromophores in skin cells, activating electron transport, adenosine triphosphate nitric oxide release, blood flow, reactive oxygen species increase, and diverse signaling pathways 3.

Applications

  • LLLT has been used in pain management for years and has been shown to reduce pain, inflammation, and promote tissue repair and healing 2, 4, 5.
  • It has beneficial effects on wrinkles, acne scars, hypertrophic scars, and healing of burns, as well as in the treatment of pigmentary disorders such as vitiligo and inflammatory diseases like psoriasis and acne 3.
  • LLLT can also reduce UV damage both as a treatment and as a prophylactic measure 3.

Efficacy

  • Studies have demonstrated analgesic and anti-inflammatory effects provided by photobiomodulation in both experimental and clinical trials 2, 4.
  • A meta-analysis showed that LLLT significantly reduced wound size and pain in skin wounds compared to control groups 4.
  • However, some studies have reported conflicting results, and higher quality trials are recommended to enhance the current evidence base 4, 6.

References

Guideline

Guideline Directed Topic Overview

Dr.Oracle Medical Advisory Board & Editors, 2025

Research

Low-level laser (light) therapy (LLLT) in skin: stimulating, healing, restoring.

Seminars in cutaneous medicine and surgery, 2013

Research

Low-Level Laser Therapy for Acute Pain: A Comprehensive Review.

Current pain and headache reports, 2023

Research

Low-level laser therapy for wound healing: mechanism and efficacy.

Dermatologic surgery : official publication for American Society for Dermatologic Surgery [et al.], 2005

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Professional Medical Disclaimer

This information is intended for healthcare professionals. Any medical decision-making should rely on clinical judgment and independently verified information. The content provided herein does not replace professional discretion and should be considered supplementary to established clinical guidelines. Healthcare providers should verify all information against primary literature and current practice standards before application in patient care. Dr.Oracle assumes no liability for clinical decisions based on this content.

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