The operation of the cold laser is not physically felt. Therefore, in no case is it uncomfortable. Only the laser light, which is very strong, can be disturbing, so it is necessary to avoid looking directly into the laser itself. In order to improve the viscosity of the blood, only a slight headache or dry throat may occur at the start of the use cycle, so we suggest that you consume enough water (at least 200 to 300ml) before you use the laser. However, if you still feel any discomfort, you can reduce the intensity of the laser and reduce the duration of the operation.In the extreme case, stop using it for a few days and then try again.