Description

A renin activity test, also called a plasma renin activity (PRA) test, is used to measure the level of renin in the blood, which helps diagnose the cause of high blood pressure (hypertension), particularly to determine if the issue is related to the adrenal glands producing too much aldosterone, a condition known as primary aldosteronism (Conn's syndrome); this is usually done in conjunction with an aldosterone test to calculate the renin-to-aldosterone ratio. 

Fasting not required.