Thursday, September 29, 2016
High Blood Pressure
Low blood pressure
My wife`s blood pressure has been 95-115 over 65-75 for a long time. She is 58 and in good health, no longer smokes, and is average height and weight. She has always had a craving for salt, and consumes a lot of salty foods as well as other junk foods. We were not concerned about her low blood pressure until she fainted after donating blood, twice in the past year. Her systolic may have been as low as 90 before giving the blood. She fainted completely away nearly an hour after giving blood, with practically no warning. She now doesn`t donate blood if her pressure is below 100 over 70 just before giving. Is her blood pressure too low? What are the consequences of low blood pressure? Can it be treated?
As long as low blood pressure is asymptomatic, it is harmless. In fact, the lower the blood pressure, the less the risk for heart disease and stroke.
However, low blood pressure that causes symptoms or leads to fainting is a matter of concern. Passing out after donating blood is not that unusual and may be harmless. If your wife generally feels well and has no problems, her low blood pressure does not require treatment.
If fainting occurs without a preceding cause (such as donating blood), a work-up for syncope is warranted. Such a work-up should include a good physical exam, measurement of blood pressure lying, sitting and standing, an ECG and some basic blood tests. Treatment would depend on the underlying cause.
Max C Reif, MD
Professor of Medicine
Director of Hypertension Section
College of Medicine
University of Cincinnati