In medicine, a pulsus paradoxus (PP), also paradoxic pulse or paradoxical pulse, is defined as an abnormally large decrease in systolic blood pressure and pulse wave amplitude during inspiration.

Assessment findings with cardiac tamponade include tachycardia, distant or muffled heart sounds, jugular vein distention and a falling BP, accompanied by paradoxical pulse (a drop in inspiratory BP by greater than 10 mmHg).

Signs which occur during an asthma attack include the use of accessory muscles of respiration (sternocleidomastoid and scalene muscles of the neck), there may be a paradoxical pulse (a pulse that is weaker during inhalation and stronger during exhalation), and over-inflation of the chest.