Home blood pressure in a cat is a median of 5 readings taken in one sitting, and the number that matters is systolic pressure under 160 mmHg. Three conditions make or break the measurement: a quiet room, 5 to 10 minutes of acclimation, and the same person doing the same thing every time. Recheck every 3 months once the cat is stable, and never adjust medication without a vet.
Why the clinic number is usually higher
A cat in an exam room is stressed, and stress alone can add 10 to 20 mmHg to a systolic reading. That is enough to turn a cat at 155 mmHg into a cat at 175 mmHg on paper and start a lifelong drug it never needed. Clinic visits also tend to produce 1 or 2 readings, taken while the cat is being held down, which is the least reliable way to measure pressure. Home readings taken over 3 to 5 sessions give a far better picture than a single clinic value.
Equipment that gives a usable number
You need a Doppler flow detector, an occluding cuff, and a sphygmomanometer, or a validated oscillometric unit designed for cats. Cuff width should be 30 to 40 percent of the limb circumference; a cuff that is too narrow reads 10 to 15 mmHg high, and one that is too wide reads low. Measure the limb with a tape at the cuff site and write the size down, so the same cuff is used every time. The tail and the forelimb give different numbers, so pick one site and stay with it. A full protocol is in blood pressure measurement.
The 3 environment rules
- Quiet room, door closed, no other pets, no television, and no conversation during the reading. A purring cat, a barking dog next door, or a phone on the table all move the number.
- 5 to 10 minutes of acclimation in the room before the cuff goes on, with the cat on a non-slip mat on a stable table, not on your lap.
- Same conditions every time: same person, same table, room at 20 to 24 °C, bladder empty, and no measurement within 30 to 60 minutes of a meal or hard play.
Restraint is the fourth hidden variable. A cat held by the scruff or pressed flat will read high; a cat sitting in a relaxed sternal position with minimal hand contact reads closest to its true pressure. If the cat fights for 60 seconds, stop, wait 5 minutes, and start again rather than pushing through.
How to take the 5 readings
Wrap the cuff, inflate to about 20 to 30 mmHg above the point where flow disappears, then deflate at 2 to 3 mmHg per second. Record the pressure at which the Doppler signal returns. Wait 30 to 60 seconds between readings, and take 5 in a row. Discard the first if it sits more than 10 mmHg above the rest, then use the median of the 5 values, meaning the third number when they are sorted. One high reading is noise; a median over 5 is data.
| Reading | Systolic (mmHg) | Pulse (per min) |
|---|---|---|
| 1 | 178 | 196 |
| 2 | 168 | 188 |
| 3 | 164 | 184 |
| 4 | 172 | 190 |
| 5 | 166 | 186 |
| Median of 5 | 168 | 188 |
What the numbers mean
Under 150 mmHg systolic is a comfortable range for a healthy cat. 150 to 159 mmHg is borderline and worth repeating over 2 to 3 weeks before any conclusion. 160 to 179 mmHg is the range where most vets start looking for a cause, and where the target of under 160 mmHg comes from. At 180 mmHg and above, the risk of damage to the eyes, kidneys, heart, and brain rises sharply, and a reading that high with sudden blindness, dilated pupils, or a seizure is an emergency, not a recheck.
Diastolic pressure is harder to measure reliably at home, so most home logs track systolic only. Record pulse rate alongside it, because a systolic reading taken with a pulse above 220 per minute usually reflects stress rather than disease.
Things that falsely raise a reading
- Cuff too narrow, or placed over a thick mat of fur without clipping a small patch.
- Cat standing, crouched, or with a limb hanging off the table edge; the cuff should sit at heart level.
- Cold room, wet fur, or a fan pointed at the cat.
- Reading within 30 minutes of eating, playing, or a carrier ride.
- Inflating the cuff too slowly, which makes the cat react to the pressure.
- More than 5 inflation cycles in one session, which turns a calm cat into a struggling one.
Every 3 months, and a written log
Once a cat is stable, recheck every 3 months, and recheck 7 to 14 days after any change in medication. If the cat is on treatment, the log is what the vet reads: date, 5 systolic values, the median, pulse rate, body weight, and anything unusual that day. A trend over 3 sessions at 3-month intervals says more than any single visit. Cats that also need glucose curves can use the same quiet setup, as described for home blood glucose curves.
Medication only on a vet's prescription
Blood pressure drugs for cats, including amlodipine, telmisartan, and benazepril, are prescription-only, and the dose depends on weight, kidney values, and whether the cat is also on diuretics. Never borrow a dose from another cat, split a human tablet, or double a missed dose. Some human products are toxic to cats at a fraction of a tablet; decongestants and cold remedies also push pressure up, and the toxicity tool lists what to keep out of reach. Ask the vet to write the target pressure and the recheck date on the prescription, so the home log has a number to compare against.
Five steps for the next session
- Book 30 quiet minutes, close the door, and put the phone away.
- Check the cuff size against the limb, aim for 30 to 40 percent of the circumference.
- Let the cat settle for 5 to 10 minutes on the table before inflating anything.
- Take 5 readings 30 to 60 seconds apart, then write the median and the pulse rate.
- Compare with the last 3 sessions; above 180 mmHg, or any sudden blindness, call the vet the same day.
Frequently asked
How many readings make a reliable home blood pressure?
Five, taken 30 to 60 seconds apart in one sitting, with the median used as the result. Drop a first reading that sits more than 10 mmHg above the rest, and compare medians across 3 sessions instead of trusting 1 number.
What systolic pressure is too high for a cat?
160 mmHg is the treatment target. Under 150 is comfortable, 150 to 159 is borderline, 160 to 179 is where most vets look for a cause, and 180 or above with sudden blindness or a seizure is an emergency.
Can I adjust the blood pressure medicine myself?
No. Amlodipine, telmisartan, and benazepril are prescription drugs dosed on weight, kidney values, and other medication. A wrong dose can drop pressure too far, so every change goes through the vet with a recheck at 7 to 14 days.