If you have high blood pressure, also called hypertension, you may wonder what the best time of day is to have it checked. The answer depends on a few factors. Among them are whether you’re doing it at home or in a healthcare facility, your schedule, and what’s most convenient for you.

Here, we look at understanding your blood pressure (BP) readings when you do take them. We also offer some tips for getting the most accurate readings when you check your blood pressure at home.

Understanding Blood Pressure Readings

Blood pressure measurements are given as two numbers. They are the systolic (top) number and diastolic (bottom) number. This is measured in millimetres of mercury (mm Hg). So a BP of 120/80 mm Hg is read as “120 over 80.”

Blood Pressure Ranges

According to the American Heart Association (AHA), there are five blood pressure categories:

• Normal: Readings of less than 120 mm Hg systolic and 80 mm Hg diastolic (less than 120/80 mm Hg)
• Elevated: Readings that consistently range from 120 to 129 mm Hg systolic and less than 80 mm Hg diastolic
• High blood pressure stage 1: Readings that consistently range from 130 to 139 mm Hg systolic or 80 to 89 mm Hg diastolic
• High blood pressure stage 2: Readings consistently at 140 mm Hg systolic or 90 mm Hg diastolic or higher.
• Hypertensive crisis: A reading that is higher than 180/120 mm Hg. This is a serious condition and requires immediate medical attention. Call your emergency line if you have symptoms of chest pain, problems breathing, back pain, numbness, weakness, vision changes, or difficulty speaking.

How to take home readings

Home BP monitoring is different from taking it at a healthcare facility because you’ll be comparing one relatively steady measurement to another over time. Follow these tips so that you get more accurate results when testing at home:

• Get readings at least twice a day. Blood pressure changes throughout the day. Your BP is typically at its lowest right after waking up. It tends to vary by up to 30% across the day. This is because of hormone changes, activity levels, and eating.
• Measure at the same time every day. The same timing should give you about the same reading, except for other influences like exercise. For example, your routine for checking your BP may be to take two to three checks both in the morning and night.
• Take more than one reading each time you check. Try to get two or three readings, one minute apart, each time you check your blood pressure. Record the results in a written log or online tracker. 
• Prepare 30 minutes ahead of readings. Do not exercise, smoke, drink caffeine, or eat a big meal for 30 minutes before you take a reading. All of these can lead to elevated readings. You should also empty your bladder and give yourself at least five minutes of quiet rest time before taking your BP. 
• Pick a convenient time. Make sure that your blood pressure checks work within your schedule. Choose a time slot that is unlikely to be disrupted by work or other conflicts. If you work outside of your home, you may want to take your BP before work or when you return.
• Sit in a chair. If you take your BP while standing up, it can lead to a higher or inaccurate reading. Sit comfortably in a chair with your back supported. Rest your arms on a table or other flat surface, and place your feet flat on the floor.

When you take blood pressure readings each day, it’s easier to see if the treatment your healthcare provider prescribed is working. Speak with a DiagnoStar Health provider today for hypertensive and cardiovascular care.