What is the correct method for patients, including older individuals or those with limited mobility or cognitive impairment, to self‑monitor blood pressure at home?

How to Self-Monitor Blood Pressure at Home: The Correct Method

Use a validated automated upper-arm device, sit quietly for 5 minutes with your back and arm supported, take 2 readings 1–2 minutes apart twice daily (morning before medication and evening) for 7 days, discard day 1, and average all remaining readings—this protocol provides the most accurate assessment of your true blood pressure. 1

Equipment Requirements

You must use only a validated automated oscillometric upper-arm device with memory storage capability. 1 Wrist monitors are not recommended for routine use because they are less reliable. 1

• Check that your device appears on validated lists at www.stridebp.org or www.dableducational.org 1
• Ensure the cuff bladder encircles 75–100% of your arm circumference—too small a cuff gives falsely high readings 1, 2
• Choose devices with automatic memory storage to prevent selective reporting of readings 3
• Bring your device to your doctor's office annually to verify accuracy 1

Pre-Measurement Preparation

Before each measurement session:

• Empty your bladder 1, 3
• Avoid caffeine, tobacco, and exercise for at least 30 minutes 1
• Sit quietly for 5 minutes in a straight-backed chair (not a sofa) 1

Correct Body Positioning

Proper positioning is critical for accurate readings:

• Sit with your back fully supported against the chair back 1
• Keep both feet flat on the floor with legs uncrossed 1
• Rest your arm on a flat surface (like a table) at heart level 1
• Position the cuff on bare skin directly above the elbow bend 1, 3
• Remain completely still and silent during measurement 1

Measurement Schedule and Technique

Follow this exact protocol for reliable results:

Daily Schedule

• Morning: Within 1 hour after waking, after urination, before breakfast, and before taking blood pressure medication 1, 3
• Evening: Before dinner or at a consistent time each evening 1, 3

Number of Readings

• Take 2 readings at each session, separated by 1–2 minutes 1
• Record every single reading—never skip or omit values 3

Duration

• Measure for 7 consecutive days 1, 3
• Discard all readings from day 1 because they show greater variability 3
• This yields 12 morning + 12 evening readings (24 total) from days 2–7 3

Calculating Your Average

Average all readings from days 2 through 7—this mean value is what your doctor will use for treatment decisions. 1, 3 Do not cherry-pick the lowest or highest readings; include every measurement. 3

Understanding Your Numbers

• Hypertension: Average home BP ≥135/85 mmHg (equivalent to office BP ≥140/90 mmHg) 1
• Elevated BP: Average 120–134/70–84 mmHg 1
• Normal: Average <120/80 mmHg 4

Home readings are typically 5–10 mmHg lower than office readings because they eliminate the white-coat effect. 4

Which Arm to Use

• Use your non-dominant arm for consistency 1
• If there is a >10 mmHg difference between arms, always use the arm with the higher reading 1, 5
• Never measure on an arm with an arteriovenous fistula or after lymph node surgery 1, 5

Common Pitfalls to Avoid

Do not take extra measurements when you feel stressed or think your pressure is high—this creates anxiety and unreliable data. 1, 4 Single high or low readings have minimal clinical significance because blood pressure varies naturally throughout the day. 1, 3

Do not adjust your medications based on home readings without consulting your doctor. 4

Do not use devices without memory storage—more than 50% of people fabricate or omit readings when recording manually. 3

Special Situations

If you have atrial fibrillation or frequent irregular heartbeats, oscillometric devices may give unreliable readings—discuss alternative methods with your doctor. 1, 5

Follow-Up Monitoring

• For stable, controlled hypertension: Repeat a 7-day monitoring period every 3 months 3
• After medication changes: Repeat monitoring 2–4 weeks later 3
• Bring your device and all stored readings to every clinic appointment 1, 4

Why This Method Works

This protocol provides superior prognostic information compared to office readings because it collects a large number of measurements, eliminates the white-coat effect, and predicts cardiovascular events more accurately. 3, 4 The 7-day average with first-day exclusion correlates best with 24-hour ambulatory monitoring and provides the most reliable estimate of your true blood pressure. 3