Apparatuses and methods for millimeter or sub-millimeter wave radiation of blood outside the body. Electromagnetic (EM) radiation length may be preset by manufacturer, programmable by the user, or dependent on sensor reading(s) of blood parameters (viscosity, color, opaqueness). Quality control measures may include sensor blood readings prior to irradiation and after irradiation by electromagnetic waves. In one embodiment emitter is connected to catheter. Applications considered include but not limited to dialysis, blood transfusion. Radiation parameters (frequency, intensity, pulse duration) may be dependent on sensor readings of blood parameters (viscosity, color, and opaqueness) enabling fine-tuning of electromagnetic signal for maximal normalization of blood parameters (including viscosity and coagulation) specific to patient. Additional apparatuses considered where emitters radiate on the body directly, for applications including but not limited to decreasing edema and/or reducing pain, and/or reducing stiffness, and/or increasing blood circulation in targeted parts of the body (e.g. legs, arms) as needed.
