Pressor Drugs for Treating Hypotension
Pressor drugs are used to treat hypotension resulting from cardiogenic shock, circulatory shock (including septic), hemorrhagic shock, and hypotension that sometimes occurs during surgical anesthesia.
Arterial pressure can be raised by increasing cardiac output and by constricting the systemic vasculature. Most pressor drugs are sympathomimetic agents that mimic the effects of sympathetic adrenergic activation on the heart (cardiostimulatory drugs) and blood vessels (vasoconstrictor drugs). Some of these drugs increase heart rate and cardiac contractility by stimulating cardiac beta1-adrenoceptors (beta-agonists). Other sympathomimetic drugs increase systemic vascular resistance by stimulating vascular alpha-adrenoceptors (alpha-agonists). Finally, there are non-sympathomimetic, vasoconstrictor drugs, such as vasopressin analogs, that have proven to be effective pressor agents.