By BitMED Provider: William Jantsch, MD; Emergency Medicine, Internal

Having uncontrolled high blood pressure is not good for anyone. Over time, elevated blood pressure increases a person’s chances of having a stroke, heart attack, heart failure, or kidney failure. Many medications are available now for safe and effective blood pressure management, and the proper use of these medicines will help a person stay healthy longer.

But how do you know if you have high blood pressure? How do you know if your blood pressure medications are working effectively?

This is where measuring your own blood pressure at home can help. Pressure readings in a doctor’s office or automated machine can be misleading: your blood pressure rises if you are even a bit anxious or in pain. The most reliable pressure readings are obtained when you are resting comfortably and feeling well.

If you take the time to monitor your blood pressure at home, and document multiple readings over time, you can take this information to your primary doctor and make important decisions regarding the need to initiate or adjust medical treatment for high blood pressure (also known as hypertension).

You will need a blood pressure monitoring device, and these come in 2 varieties. “Manual” and “automatic”. With a manual cuff (also known as a sphygmomanometer), you will also need a stethoscope to listen for the beating sounds in the artery while the measurement is being taken. This is difficult for a person to do by him or herself, and takes a bit of practice and training. So, even though manual cuffs are inexpensive ($10-20), they may not be good for you. The automated devices can be purchased for $40-60, and even less when used. Such a device works simply by turning the monitor on, applying the cuff to the upper arm, and the pushing a button. The reading is automatic. Easy!

A word of caution: make sure you get a blood pressure cuff that fits your arm properly (extra-large cuffs are made for people with large arms). Also, some people have had good results with monitors that take the pressure at the wrist, but I have found these to produce inaccurate readings on occasion.

Understanding the numbers:

Blood pressure is recorded with two numbers, divided by a slash mark:

Systolic blood pressure/diastolic blood pressure

“Systolic” pressure is the maximum pressure (in millimeters of Mercury) when the heart is beating

“Diastolic” pressure is the minimum pressure in the arteries when the heart is in between beats

Good blood pressure levels:

120/80 is generally considered “normal”

Many doctors will not advise starting blood pressure medications until the numbers go over 140/90 or higher, depending on a patient’s age and other medical conditions.

What if the blood pressure reading is really high?

Well, first of all, don’t panic. Elevations as high as 180/100 can be seen in otherwise healthy people if they are under acute stress or in severe pain. People with known hypertension will occasionally generate blood pressures of 220/120 under certain circumstances.  It is important to keep a log of these pressures.  You do not want to stay at these levels for long periods of time.  Always discuss your findings with your doctor.