Low blood pressure, also known as hypotension, is generally defined as a blood pressure reading lower than 90/60 mm Hg. This means the systolic pressure (the top number, when the heart beats) is less than 90 mm Hg, and/or the diastolic pressure (the bottom number, when the heart rests between beats) is less than 60 mm Hg
. While low blood pressure is often not harmful and can be normal for some people, it is considered "too low" when it causes symptoms or indicates an underlying health problem. Symptoms of dangerously low blood pressure include dizziness, fainting, confusion, nausea, fatigue, blurred vision, heart palpitations, and in severe cases, shock due to insufficient blood flow to vital organs
. Types of low blood pressure include:
- Orthostatic (postural) hypotension: a sudden drop in blood pressure when standing up, common in older adults.
- Postprandial hypotension: a drop in blood pressure after eating, mostly affecting older adults
Low blood pressure can be caused by various factors such as dehydration, heart problems, hormonal disorders, certain medications, pregnancy, and neurological conditions
. In summary, blood pressure below 90/60 mm Hg is considered low, but it is only "too low" when it causes symptoms or health complications requiring medical attention
