Immune dysregulation refers to the malfunctioning of the immune system, where it either overreacts or underreacts to stimuli. This can lead to a variety of health issues, including autoimmune diseases, allergies, and an increased susceptibility to infections. The immune system is designed to protect the body from harmful pathogens, but when it is dysregulated, it can mistakenly target the body's own cells or fail to adequately respond to invaders.