What is the recommended time to check blood pressure (BP) at home?

Recommended Timing for Home Blood Pressure Monitoring

Home blood pressure should be measured twice daily—in the morning before breakfast and before taking medications (but not immediately after awakening), and in the evening before dinner or at bedtime—with measurements taken for at least 3 days and ideally 7 consecutive days. 1

Optimal Daily Measurement Schedule

Morning Measurements

• Take readings before breakfast and before taking antihypertensive medications, but not immediately after awakening 1, 2
• Morning measurements provide the most reliable home blood pressure values throughout the day, with the smallest standard error of measurement (3.0 mmHg) 3
• Morning hypertension specifically predicts stroke risk, particularly among patients taking antihypertensive medications 4

Evening Measurements

• Take readings before dinner or at bedtime 1, 2
• Evening blood pressure variability has prognostic significance and independently predicts hard cardiovascular events beyond blood pressure level 5
• While evening readings are equally predictive as morning readings when analyzed as continuous variables, morning-specific hypertension carries higher stroke risk 4

Measurement Protocol Per Session

Number of Readings

• Take 2 readings at each measurement session, separated by 1-2 minutes 1, 6
• Some guidelines recommend 2-3 readings per session during initial assessment 1, 2
• Average all readings from each session 1

Duration of Monitoring Period

• Measure for a minimum of 3 days and ideally 7 consecutive days 1, 7
• Discard the first day's measurements from analysis 1, 8
• This provides approximately 12 morning and 12 evening readings for clinical decision-making 1
• If the 3-day average is close to the treatment threshold, continue measuring for the full 7 days 1

Pre-Measurement Preparation Requirements

Timing Restrictions

• Avoid tobacco, caffeine, and exercise for 30 minutes before measurement 1, 2, 6
• Empty bladder before measuring 1, 6
• Rest quietly for 5 minutes in a seated position 1, 8, 6

Proper Positioning

• Sit with back straight and supported, feet flat on the floor with legs uncrossed 1, 8, 2, 6
• Support arm on a flat surface at heart level 1, 8, 2
• Remain silent during the entire measurement period 8

Frequency for Different Clinical Scenarios

Initial Assessment

• Measure for 7 consecutive days (excluding day 1) when first beginning home monitoring 1, 8

Dose-Titration Phase

• Measure after 2-4 weeks when initiating or adjusting antihypertensive therapy 1
• Maintain identical conditions and times as initial measurements 1
• Take measurements as trough values (before medication) 1

Long-Term Monitoring

• For stable, controlled patients: measure for a minimum of 1 week per quarter (every 3 months) 1, 9
• Measure more frequently in patients with poor compliance 1

Diagnostic Thresholds

• Hypertension is defined as average home BP ≥135/85 mmHg (equivalent to office BP ≥140/90 mmHg) 1, 8, 7
• Elevated BP is defined as 120-134/70-84 mmHg 1, 8
• Target home BP goal is <135/85 mmHg, or <130/80 mmHg for patients with diabetes, coronary heart disease, or chronic kidney disease 1, 2

Common Pitfalls to Avoid

• Do not measure immediately after awakening—allow time for the body to adjust before taking morning readings 1, 2
• Do not include first-day measurements in the average—these typically show greater variability 1, 8
• Do not rely on single-day measurements—at least 12 total readings over multiple days are needed for reliable assessment 1
• Ensure annual verification of device accuracy and patient technique 1, 8