Anaphylactic shock is a severe and potentially life-threatening allergic reaction that occurs rapidly after exposure to an allergen, such as certain foods, medications, or insect stings. It is characterized by symptoms like difficulty breathing, swelling, a rapid drop in blood pressure, and loss of consciousness. Immediate treatment with epinephrine is crucial to counteract the symptoms and stabilize the individual. If not treated promptly, anaphylactic shock can lead to serious complications or death.