Class IV Laser: What It Is
A Class IV laser is a high-powered therapeutic laser used in medical and veterinary settings for pain relief, tissue healing, and inflammation reduction. Lasers are classified by the FDA based on power output and potential risk. Class IV lasers operate above 500 milliwatts, giving them significantly greater energy-delivery capabilities compared to lower-class therapeutic lasers (Class I–III). Because of their power, they require trained professionals and appropriate safety measures, including protective eyewear and controlled treatment environments.

How Class IV Laser Therapy Works
Class IV lasers use specific wavelengths of light—typically in the near-infrared spectrum—to penetrate deep into tissues. When this light energy reaches cells, it is absorbed by structures called chromophores, especially within the mitochondria. This triggers a process called photobiomodulation, which boosts cellular energy production (ATP), increases circulation, modulates nerve impulses, and promotes faster repair of damaged tissues. The higher power output of Class IV lasers allows more light energy to reach deeper structures like muscles, tendons, and ligaments, making treatment more efficient.

Benefits of Class IV Laser Therapy
The increased power and deeper penetration offer several therapeutic benefits. These include reduced pain through anti-inflammatory effects and decreased nerve sensitivity, faster healing of soft-tissue injuries, improved blood flow, reduced muscle spasms, and enhanced mobility. Class IV lasers are commonly used for conditions such as arthritis, tendonitis, sports injuries, neuropathy, back and neck pain, and post-surgical recovery. Many patients experience rapid relief after a few treatments, and the therapy is typically non-invasive, drug-free, and well-tolerated when applied by trained professionals.