Low Blood Pressure: When It Matters and When It Doesn't

High blood pressure gets most of the attention, but blood pressure that is too low can cause problems too.

What the numbers mean

Blood pressure is the force of the blood pushing against the walls of the arteries. It is highest each time the heart beats and pumps blood out: that is the systolic pressure. Between beats, while the heart rests, it falls: that is the diastolic pressure. A reading gives both numbers, one above or before the other, as in 120/80.

A reading of 90/60 or lower is low blood pressure.

When low is a problem

• Some people have low blood pressure all the time. They have no symptoms, and the low readings are normal for them.
• In others it drops below normal because of a medical condition or certain medicines.
• Some people get symptoms when they stand up too quickly.

Low blood pressure is a problem only if it causes dizziness, fainting or, in extreme cases, shock.

Sources

• MedlinePlus, U.S. National Library of Medicine, "Low Blood Pressure," from the NIH National Heart, Lung, and Blood Institute. https://medlineplus.gov/lowbloodpressure.html
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