Low-level photon therapy uses lasers or light emitting diodes to produce a very bright monochromatic light of a single wavelength. This vibrating energy source can be used to stimulate specific acupuncture points or to treat larger areas of injury or disease. Infra red and red light are the most common wavelengths used. Infra red light is invisible but can penetrate tissue to a greater depth than red light. The desired energy output that results in cellular healing is 1-10 joules per square centimeter. LEPT has been shown to influence cellular function in the following ways:

1.  by accelerating the healing of wounds
2. by stimulating cell replication
3. by increasing production of DNA and RNA
4. by stimulating collagen production (collagen is the main supportive protein of the skin, tendon, bone, cartilage and connective tissue) 4) by stimulating the immune system
5. by Improving circulation. Large pads containing multiple light emitting diodes can be used to treat large areas over the pets back.

A probe containing only one diode is used to treat individual acupuncture points. The light-emitting probe produces no sensation and therefore is very helpful when performing acupuncture on pets that are sensitive to needles. Ruptured intervertebral disks are often very effectively treated with LEPT.