Red Light Therapy in Thrombosis and Hemostasis.

Abstract

Red light therapy is emerging as a potential non-pharmacological modulator of thrombosis and hemostasis. Photobiomodulation with red, near-infrared (NIR), and far-infrared (FIR) wavelengths has been shown to influence nitric oxide release, endothelial function, platelet activation, and vascular tone. These effects align to components of Virchow's triad (i.e., endothelial dysfunction, hypercoagulability), and ameliorate thromboinflammation. Experimental data indicate that photobiomodulation may be effective to reduce platelet aggregation, von Willebrand factor activity, and improve microvascular perfusion. However, controversy remains regarding whether observed benefits reflect active red/NIR effects or simply the exclusion of pro-thrombotic blue light. Limitations in tissue penetration, protocol standardization, and translational modelling pose challenges for clinical implementation. Despite these uncertainties, red light therapy offers promise in high-risk patients where conventional anticoagulation is limited by bleeding risk. Future studies must define optimal dosing parameters, clarify mechanistic pathways, and evaluate efficacy in randomized clinical trials to establish its role in contemporary thrombosis management.