Is it normal to feel lightheaded after giving blood?

Is it normal to feel lightheaded after giving blood?

1. Introduction Feeling lightheaded after donating blood is a normal, transient physiological reaction to an acute reduction in total blood volume. This sudden fluid loss triggers a temporary drop in blood pressure, which slightly reduces cerebral perfusion until the autonomic nervous system adapts. While common and usually benign, understanding this hemodynamic shift helps donors prevent … Read more