The American Heart Association website provides information about low blood pressure and the circumstances in which individuals should seek medical attention, according to the American Heart Association. Low blood pressure isn't normally cause for concern, so the website lists accompanying symptoms that point to an underlying health problem.
The Mayo Clinic website, which is certified by Health On the Net Foundation, according to its About page, is another credible source for information on low blood pressure, also known as hypotension. The website defines the pressure measurements doctors identify as hypotension, and it discusses the difference between systolic and diastolic pressure. Mayo Clinic also explains possible causes of low blood pressure, common tests used to diagnose the condition and situations when patients may require treatment.