What Is Class 4 Laser Therapy?
Class IV Laser Therapy—often referred to as High-Power Laser Therapy or Photobiomodulation Therapy (PBMT)—is a non-invasive treatment that uses specific wavelengths of light to stimulate healing, reduce pain, and decrease inflammation at the cellular level. It has become a widely adopted tool in orthopedic clinics, sports medicine, physical therapy, chiropractic, and veterinary medicine due to its ability to accelerate tissue repair without drugs or surgery.
Backed by decades of research in photomedicine and tissue healing, Class IV lasers represent one of the most advanced regenerative technologies available today.
Understanding the Basics of Class 4 Laser Therapy
Laser therapy works by delivering concentrated light energy into the body. Unlike surgical lasers that cut tissue, therapeutic lasers are designed to penetrate the skin safely and stimulate biological processes that promote healing. Class IV lasers are defined by their higher power output (greater than 500 milliwatts), allowing them to:
- Penetrate deeper into tissue
- Deliver therapeutic energy more efficiently
- Treat larger areas in shorter periods of time
- Reach muscles, ligaments, tendons, and joints
This makes them particularly effective for treating both acute injuries and chronic conditions.
How Does Class IV Laser Therapy Work?
The science behind laser therapy is known as photobiomodulation. When light photons enter the body, they interact with cells and trigger a cascade of physiological responses that support recovery and pain relief.
Key mechanisms supported by clinical research include:
Common Conditions Treated with Class 4 Laser Therapy
Class IV Laser Therapy is used to treat a wide range of musculoskeletal and neurological conditions, including:
Common clinical areas where class 4 laser therapy is used:
- Joint Pain
- Knee pain
- Shoulder pain
- Hip pain
- Arthritis
- Soft Tissue Injuries
- Sprains and strains
- Tendonitis and tendinopathy
- Ligament injuries
- Muscle tears
- Spine Conditions
- Neck pain
- Lower back pain
- Disc-related discomfort
- Chronic Conditions
- Plantar fasciitis
- Carpal tunnel syndrome
- Frozen shoulder
- Post-Surgical Recovery
- Incision healing
- Scar tissue management
- Swelling reduction
- Neurological Symptoms
- Nerve irritation
- Peripheral neuropathy
It is frequently used in both acute injury settings and long-term chronic pain management.
What Happens During a Class 4 Laser Treatment?
A Class IV laser therapy session is simple, comfortable, and typically takes only a few minutes.
Treatment plans often involve multiple sessions over several weeks to achieve optimal results.
What Makes Class IV Lasers Different?
Compared to lower-power lasers (Class I–III), Class IV systems offer:
- Deeper tissue penetration
- Faster treatment times
- Higher energy delivery
- Greater ability to treat large muscle groups and joints
This allows clinicians to address both superficial and deep tissue injuries more effectively.
Class 4 Laser Therapy in Human and Veterinary Medicine
Class IV laser therapy is widely used in both human and veterinary medicine, which further supports its biological effectiveness.
In veterinary care, it is commonly used for:
- Osteoarthritis in dogs
- Post-operative healing
- Tendon and ligament injuries in horses
- Wound care
The consistent results across species reinforce its role as a regenerative therapy rather than simply a symptom-relief tool.
The Role of Laser Therapy in Modern Medicine
Healthcare is increasingly shifting toward non-invasive, regenerative solutions that help the body heal naturally. Class IV laser therapy is becoming a cornerstone of this movement because it:
- Targets the root cause of pain
- Stimulates natural repair processes
- Supports faster recovery
- Can be combined with other therapies
It is frequently used alongside physical therapy, rehabilitation, and regenerative treatments to improve outcomes.
Final Thoughts on Class 4 Laser Therapy
Class IV laser therapy represents a powerful advancement in non-invasive medicine. By using light to stimulate healing at the cellular level, it offers a drug-free, surgery-free option for reducing pain, improving mobility, and accelerating recovery.
For patients dealing with chronic pain, inflammation, or injury, it provides a clinically supported pathway toward healing that focuses on restoration rather than temporary relief.
As research continues to grow, Class IV laser therapy is emerging as one of the most important tools in modern rehabilitation and regenerative care.
References
- Hamblin MR. Photobiomodulation or low-level laser therapy. J Biophotonics. 2016;9(11–12):1122–1124.
- Hamblin MR, Demidova TN. Mechanisms of low level light therapy. Proc SPIE. 2006;6140.
- Chung H, Dai T, Sharma S, Huang Y, Carroll J, Hamblin MR. The nuts and bolts of low-level laser therapy. Ann Biomed Eng. 2012;40(2):516–533.
- Karu T. Primary and secondary mechanisms of action of visible to near-infrared radiation on cells. J Photochem Photobiol B. 1999;49(1):1–17.
- Passarella S, Karu T. Absorption of monochromatic and narrow band radiation in the visible and near IR by cytochrome c oxidase and its role in photobiomodulation. J Photochem Photobiol B. 2014;140:344–358.
- Bjordal JM, Johnson MI, Iversen V, Aimbire F, Lopes-Martins R. Low-level laser therapy in acute pain: A systematic review of possible mechanisms of action and clinical effects. Photomed Laser Surg. 2006;24(2):158–168.
- Aimbire F, et al. Low-level laser therapy induces dose-dependent reduction of TNF-α levels in acute inflammation. Photomed Laser Surg. 2006;24(1):33–37.
- Hode L, Tunér J. Low level laser therapy: clinical practice and scientific background. Prima Books AB. 2014.
- de Freitas LF, Hamblin MR. Proposed mechanisms of photobiomodulation. IEEE J Sel Top Quantum Electron. 2016;22(3).
- Enwemeka CS, Parker JC, Dowdy DS, et al. The efficacy of low-power lasers in tissue repair and pain control: A meta-analysis study. Photomed Laser Surg. 2004;22(4):323–329.
- Medrado AR, Pugliese LS, Reis SR, Andrade ZA. Influence of low level laser therapy on wound healing and its biological action upon myofibroblasts. Lasers Surg Med. 2003;32(3):239–244.
- Chow R, et al. Efficacy of low-level laser therapy in the management of neck pain: A systematic review and meta-analysis. Lancet. 2009;374(9705):1897–1908.
- Bjordal JM, et al. Low-level laser therapy for tendinopathy. Phys Ther Rev. 2003;8(2):91–99.
- Alayat MS, et al. High-intensity laser therapy in the treatment of chronic low back pain. Lasers Med Sci. 2014;29(3):1065–1073.
- Angelova A, Ilieva E. Effectiveness of high intensity laser therapy for reduction of pain in knee osteoarthritis. Pain Res Manag. 2016.
- Ryan T, et al. Effect of laser therapy on pain and function in dogs with osteoarthritis. Front Vet Sci. 2018.
- Looney AL, et al. Photobiomodulation therapy in veterinary medicine. Vet Clin North Am Small Anim Pract. 2018.
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The Softshock 2.0 radial pressure wave device delivers a targeted mechanical stimulus that supports circulation, tissue stimulation, and pain relief. Learn how shockwave fits into daily clinical routines as a focal, efficient intervention for localized musculoskeletal presentations.
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Disclaimer:
Medray Laser & Technology manufactures and distributes FDA-cleared medical devices designed to support circulation, tissue stimulation, and pain relief. Our products are intended for use by licensed healthcare professionals. While clinical research and practitioner experience support the use of laser and radial pressure wave (RPW) therapy in various applications, some uses described in this article may be considered off-label and are not explicitly cleared by the FDA. Patients should consult their healthcare provider to determine the best treatment for their individual needs. The information provided in this article is for educational purposes only and should not be considered medical advice or a substitute for consultation with a licensed medical professional.
Educational content is for licensed healthcare providers and may include discussion of clinical uses not cleared by the FDA. Provided for scientific exchange and not intended as promotional.
The FDA has cleared therapeutic lasers and shockwave devices for increasing circulation, tissue stimulation, and pain relief. Some of the use cases described in this article reflect how clinicians may apply shockwave therapy in practice, based on peer-reviewed research. This information is provided for educational purposes only and does not imply FDA clearance or approval for specific conditions.