Low level therapy uses cold subthermal laser light energy to direct bio-stimulative light energy to the body cells without injuring or damaging them in any way. In laser therapy the trial, the researchers at the University of California, San Diego used the NeuroThera laser system within 24 hours of stroke onset, with the average time to treatment being 14. They are the class of lasers that have many therapeutic applications in medicine. The energy is applied in fractional way in which tiny columns of thermal damage are spaced so that tissue between each is spared, which in turn leads to faster healing process. This includes any area that has been treated with prolotherapy injections. -host disease in which low-level laser therapy applied to the oral mucosa, in addition to standard systemic immunosuppressive treatment, resulted in quick healing and symptomatic relief. The 14 patients treated with ALA PDT received one to six treatments depending on the severity of their acne and continued to use topical medications during and after the study.