Why is my blood pressure low enough to make me weak and dizzy?

Howard E. Lewine, MD
Hospitalist
No specific blood pressure reading is considered too low. It always depends upon how the person is feeling and his or her general health.

In your case, it's clear that your blood pressure level is too low when you feel weak and dizzy. When this symptom occurs, you should immediately lie down. If that is not possible, at least sit down. If you continue to stand while feeling lightheaded, you could faint and hurt yourself.

There are many possible causes of low blood pressure. My approach is to review all medications that the person is taking. If you take blood pressure pills or heart medications, the dose may be too high for you. Many other medications can lower blood pressure.

Next, I make sure the person has been drinking enough fluids. You might not feel thirsty, but could be mildly dehydrated. Also, many people restrict their salt intake. Usually this is healthy. But people with low blood pressure may actually need to increase the amount of salt in their diet.

These two factors, medications and dehydration, account for the great majority of low blood pressure episodes. If neither of these applies to you, you could have postural hypotension. In this condition, blood pressure falls dramatically when someone stands. Usually this is caused by problems with the nerves that help regulate blood pressure. People who have had diabetes for a long time can have this problem.

You should definitely contact your doctor if you think one of your medications is causing the low blood pressure or the problem does not quickly go away by increasing your fluid intake.
Harvard Medical School Hypertension: Controlling the 'silent killer'

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Harvard Medical School Hypertension: Controlling the 'silent killer'

An alarming one in three American adults has high blood pressure. Known medically as hypertension, many people don't even know they have it, because high blood pressure has no symptoms or warning...

Continue Learning about Hypotension

Hypotension

Clinically known as hypotension, low blood pressure (LBP) may indicate signs of underlying health problems.While its common for some people to always have hypotension, severe drops in your blood pressure can deprive your body of o...

xygen and result in damage to vital organs. Sudden drops may be caused by heart failure, loss of blood, an allergic reaction called anaphylaxis or sepsis, a life-threatening blood infection. Doctors define a reading below 90/60 as low blood pressure. You may become dizzy or even faint if your pressure falls below this reading. As you get older, you are more likely to develop either high or low blood pressure. Medications that help treat high blood pressure may actually cause you to have low blood pressure.
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Important: This content reflects information from various individuals and organizations and may offer alternative or opposing points of view. It should not be used for medical advice, diagnosis or treatment. As always, you should consult with your healthcare provider about your specific health needs.