A printable blood pressure log

Blood pressure moves all day. It climbs when you stand up, when you're in pain, when you're late for an appointment and the parking lot was full. A single reading in a clinic (often the most stressful moment of the week) tends to run high for exactly that reason. There's even a name for it: white-coat hypertension.

What your doctor wants is the pattern. A week or two of readings taken calmly at home, at the same times each day, tells them far more than any one number can. A log is how you hand them that pattern instead of a guess.

Every blood pressure reading has two numbers and most monitors show a third. Capture all of them, plus a couple of details that explain the outliers.

The reading is only as good as the setup. Sit for five minutes before you start, feet flat on the floor, back supported, arm resting on a table at about the height of your heart. Don't talk during the measurement, and skip caffeine or a cigarette for half an hour beforehand.

Use the same arm each time and note which one. Take two readings about a minute apart; if they're far apart, take a third. Write down what you see, not a rounded or rosier version. The log only helps if it's honest.

Take your two readings morning and evening for at least four days, ideally seven. Then leave out the first day and average the rest. That's how the UK's national guideline (NICE NG136) turns a home log into one number, and the CDC's home guidance sets up each reading the same way.

Six days of morning and evening pairs comes to about two dozen readings. That's a steadier picture than any single reading at the clinic. Bring the average along with the sheet.

These are the standard American Heart Association categories, useful for reading your own log at a glance. They are a reference, not a diagnosis. Your personal target may be different, especially with kidney disease, diabetes, or a heart condition, so ask your doctor what range they want for you.

The categories above are written for clinic readings. The ACC/AHA guideline gives the home version of each cutoff, and they match through stage 1: a home average of 120/80 means the same as a clinic 120/80, and so does 130/80. They split at stage 2, where a home average of 135/85 counts the same as a clinic 140/90.

Matching cutoffs don't mean matching readings. Your home numbers can still run lower than your clinic ones, thanks to the white-coat effect from earlier. Compare your average to the target your doctor wrote at the top of the sheet.

A blank grid is easy. The Notes column is the hard part, so here are three rows filled in the way they should be.

Look at the middle row. Without its note, 152/94 is a frightening number with nothing attached to it. With it, your doctor knows a dose was missed and coffee was involved, and can weigh the reading against that. Write the note while it's happening. Nobody remembers on Friday what went on at Wednesday bedtime.

Sometimes the request is different: take it lying down, then take it again standing. That's a check for orthostatic hypotension, the drop in pressure that makes someone dizzy when they stand up too fast. It matters most for older adults and for anyone on blood pressure or heart medication.

In the standard version, they lie flat and rest at least five minutes before the first reading. Then they stand, and you take another reading at one minute, two minutes, and three minutes. Have someone stand beside them in case they get dizzy, and sit them down right away if they do.

Write all four readings in the log, mark the position next to each one, and note the minute any dizziness started. The consensus definition of a drop worth reporting is a fall of at least 20 points systolic or 10 points diastolic within three minutes of standing.

Bring the numbers, not the conclusion. A drop that size, especially alongside dizziness, is something to tell the doctor about. Don't act on it by changing a dose yourself.