Anaphylactic shock is a severe and generalized hyperacute allergic reaction caused by the release of large quantities of histamine and similar substances into the bloodstream. The triggering cause stems from the introduction of external allergenic substances into the animal's body through the administration of drugs, insect bites, food, or blood transfusions, which produce a massive antigen-antibody reaction.
This cow manifested the first symptoms 5 minutes after an intramuscular injection of an antihemorrhagic drug: serous rhinorrhea, ptyalism, edema of the eyelids and pinnae, lacrimation, respiratory distress, and coughing due to pharyngeal and laryngeal edema (in the most severe cases, these can lead to the animal's suffocation within a short time)...
