Systemic photobiomodulation: an integrative review of evidence for intravascular laser irradiation of blood and vascular photobiomodulation.

Currently, clinical practice has demonstrated various applications for systemic laser photobiomodulation (PBM). In recent years, an increasing number of studies have been highlighted in the literature; however, they differ in their application methods, which can be intravenous, referred to as ILIB (intravascular laser irradiation of blood), or transdermally, recently termed VPBM (vascular photobiomodulation). This review aimed to compile all findings on these techniques and critically discuss their results. A search for articles was conducted in the PubMed, Scopus, and Web of Science databases using Medical Subject Headings (MeSH) to select descriptors with the boolean operators "AND/OR." After applying inclusion and exclusion criteria, 37 articles were selected. Of these, 19 studies discussed the use of systemic PBM with intravenous application, and 7 studies reported transcutaneous application. Regarding clinical studies, 28 studies addressed the application of the techniques in respiratory, cardiovascular, metabolic, neurological, and musculoskeletal conditions. For preclinical studies, 9 articles primarily discussed the application of systemic PBM in pulmonary and musculoskeletal conditions. Despite the promising results, methodological limitations, and variabilities in studies on systemic laser PBM prevent the categorical assertion of its efficacy. It is essential to conduct rigorous new studies to elucidate the mechanisms of action and determine the technique's efficacy.