Heart & Vascular Health
blood pressure reading

When Blood Pressure Goes Too Low

When not to worry and when to be concerned

You know that eating a healthy diet helps lower blood pressure, but blood pressure that is too low could be a cause for concern as well. Labeling blood pressure readings as “too low” depends more on your current and past health history than on the numbers on your blood pressure unit.

Your personal normal

Normal blood pressure is 120 mmHg systolic and 80 mmHg diastolic but what is low blood pressure, exactly?

Your blood pressure needs to be high enough to do its job – supplying blood and providing vital oxygen to your limbs, organs and brain.

Cardiologist Michael Faulx, MD, explains, “A young healthy patient may have a resting blood pressure of 90/60 mmHg and feel absolutely fine.” On the other hand, “an older patient with an existing heart problem such as aortic stenosis (narrowing of the aortic valve) might feel weak and dizzy with a blood pressure of 115/70 mmHg.”

Why problems occur

Dr. Faulx explains, “Blood pressure depends on three things; stroke volume (amount of blood ejected from the heart per beat), heart rate and blood vessel tone (how clear and flexible your blood vessels are). Disorders that affect any of these three things can result in low blood pressure.” 

Heart failure combined with low stroke volume can spell trouble if a person’s blood vessels are unable to respond properly in order to maintain adequate blood pressure. Excessively slow heart rate (bradycardia) also can result in dangerously low blood pressure.

Some conditions can impair blood vessel health and result in low blood pressure.  Examples include infections (sepsis), paralysis (injury or stroke-related) and certain endocrine disorders such as low cortisol levels. 

Medications are one of the most common reasons for too-low blood pressure.   

Fluctuating blood pressure

Certain conditions called autonomic disorders cause the tone of the blood vessels and even the heart rate to fluctuate widely. As a result, blood pressure also fluctuates widely.

Medications can sometimes cause blood pressure to go up and down, particularly shorter-acting blood pressure medications that act fast, but result in a “rebound” increase in blood pressure and heart rate when they wear off. 

When to call the doctor

Consult your doctor if you experience symptoms such as lightheadedness, fainting or feeling weak, as these symptoms might be related to too-low blood pressure. 

Anyone who has existing kidney or liver problems, or anyone who has had a stroke or who might be at risk for stroke should have their blood pressure monitored carefully. Insufficient blood pressure could restrict critical blood supply to the organs and the brain.

Dr. Faulx assures the general public, “For otherwise healthy people, call your doctor if you have low blood pressure and you don’t feel well or have no energy.  If you feel perfectly fine, then odds are your blood pressure, even if lower than average, is probably OK for you.”

Tags: blood pressure, blood vessels, heart and vascular institute, heart health, low blood pressure
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    • The_Beating_Edge_Team

      It depends on the case, but usually low blood pressure after surgery is caused by low blood volume, dehydration, or perhaps the anesthesia or medications you had, or other conditions. Use of fluids and medications can help the blood pressure as well as heart rate. Sometimes a pacemaker may be needed (temporary or permanent) if the heart rate gets too low. If you have concerns, you should speak to your surgeon – he or she can talk to you about your specific condition, what occurred after your surgery, and if you need to be concerned in the future. betsyRN



  • Ashleigh LaGraves

    Had my blood pressure tested at my doctors and was 120/42. Why is the bottom number so low while the other is fairly normal. I do feel dizzy occasionally but am worried I might have a problem. Doctor said they will keep an eye on it. I have an iron/anemia disorder as well and am 29.

  • Smith

    When not. To worry NOT TOO. GET A PROOFREADER PLEASE. All advice sounds ignorant using the wrong word !

  • kimbee785

    I’ve been suffering form headaches recently, my BP is 149/109 right now. I have been on metoprolol for years and only recently have been having these problems. Today I was prescribed Lisinoprl 5mg twice a day along with the my metoprolol 25mg twce a day. I didn’t think to ask the doctor wat to do if this makes my BP drop to dangerous level. I am diabetic, and recovering from Breast Cancer and uterine cancer. I have had 2 aneurysms in the past (2007). I used to suffer from massive headaches until 2 years after the brain sugery. Now they have returned. Just today recieved a prescription for Butal/Aceamin/caf 50-325-40. Doctors office is closed, I am fearful of taking the new medicine until I am able to talk to him tomorrow…should I be?

    • The_Beating_Edge_Team

      I can not give medical advice – but your blood pressure is high and needs to be lower. I am hoping you were able to speak to your doctor and have this resolved. Please let us know if you need any help in the future. This blog is not reviewed every day for new questions – so this is not the best place for rapid responses. Sorry! Are you taking your new med? Are you feeling any better? Are you monitoring your blood pressure? Signs of low blood pressure are dizziness, fatigue, nausea – here is a page that may help you: http://www.heart.org/HEARTORG/Conditions/HighBloodPressure/AboutHighBloodPressure/Low-Blood-Pressure_UCM_301785_Article.jsp betsyRN