Light-emitting diode phototherapy: pain relief and underlying mechanisms.

Pain is a common symptom of an illness. For decades, pain treatments such as non-steroidal anti-inflammatory drugs, opioids, and surgical nerve blocking have been widely used, but each method has its limitations. Photobiomodulation is a recently developed method for pain management, with light-emitting diodes (LEDs) being a more recent development used in pain management because of their low cost, low side effects, and high safety. Here, we reviewed the phototherapeutic effects of LEDs on different pain conditions. We also discussed possible physicochemical and neurobiological mechanisms underlying LED therapy, especially its effects on inflammatory pain.