Orthostatic Hypotension

Orthostatic hypotension, also known as postural hypotension, and colloquially as head rush or dizzy spell, is a form of hypotension in which a person's blood pressure suddenly falls when standing up or stretching. The symptom is caused by blood pooling in the lower extremities upon a change in body position. It is quite common and can occur briefly in anyone, although it is particularly prevalent among the elderly, and those with low blood pressure.