Alpha-1 receptor agonists are primarily found in the blood arteries and heart. When these receptors are triggered, blood arteries constrict, resulting in higher blood pressure, increased heart effort, and lower cardiac output. Alpha-1 receptor agonists are a type of medicine used to treat a variety of illnesses, including vasodilatory shock, hypotension, hypoperfusion, heart failure, lower acuity situations, cardiopulmonary arrest, and septic shock.