There are several types of hypotension. People who always have low blood pressure have chronic asymptomatic hypotension. They usually have no signs or symptoms and need no treatment. Their low blood pressure is normal for them.
Other types of hypotension occur if blood pressure suddenly drops too low. The signs and symptoms range from mild to severe.
The three main types of this kind of hypotension are orthostatic (OR-tho-STAT-ik) hypotension, neurally mediated hypotension, and severe hypotension linked to shock.
This type of hypotension occurs when standing up from a sitting or lying down position. You may feel dizzy or light-headed, or you may even faint.
Orthostatic hypotension occurs if your body isn't able to adjust blood pressure and blood flow fast enough for the change in position. The drop in blood pressure usually lasts only for a few seconds or minutes after you stand up. You may need to sit or lie down for a short time while your blood pressure returns to normal.
Orthostatic hypotension can occur in all age groups. However, it's more common in older adults, especially those who are frail or in poor health. This type of hypotension can be a symptom of another medical condition. Thus, treatment often focuses on treating underlying conditions.
Some people have orthostatic hypotension, but also have high blood pressure when lying down.
A form of orthostatic hypotension called postprandial hypotension is a sudden drop in blood pressure after a meal. This type of hypotension mostly affects older adults. People who have high blood pressure or a central nervous system disorder, such as Parkinson's disease, also are at increased risk for postprandial hypotension.
Neurally Mediated Hypotension
With neurally mediated hypotension (NMH), blood pressure drops after you've been standing for a long time. You may feel dizzy, faint, or sick to the stomach as a result. NMH also can occur as the result of an unpleasant, upsetting, or scary situation.
NMH affects children and young adults more often than people in other age groups. Children often outgrow NMH.
Severe Hypotension Linked to Shock
Shock is a life-threatening condition in which blood pressure drops so low that the brain, kidneys, and other vital organs can't get enough blood to work well. Blood pressure drops much lower in shock than in other types of hypotension.
Many factors can cause shock. Examples include major blood loss, certain severe infections, severe burns and allergic reactions, and poisoning. Shock can be fatal if it's not treated right away.