Dogs and humans have a lot in common. This includes, unfortunately, a few health conditions. Blood pressure is one of them. Just like in humans, a dog’s blood pressure can run too high (hypertension) or too low (hypotension).
The difference is your dog can’t tell you they feel dizzy. That’s where we hoomans come in. As principal partner of Healthy Pets New Zealand and Dogs New Zealand, PD Insurance is all about helping Kiwi pet parents spot health issues early.
In this article
What is dog hypertension and hypotension?
Blood pressure is the force your dog’s blood exerts against their artery walls. Hypertension means that force is consistently too high; hypotension means it’s too low.
The two behave very differently. High blood pressure is a slow burn. It quietly damages the kidneys, eyes, heart and brain over months or years, often with no obvious symptoms until real harm is done. Low blood pressure is sudden, and almost always an emergency, because it means organs aren’t getting enough oxygen right now.
One thing to know up front. In dogs, hypertension is nearly always secondary, meaning it’s a symptom of another disease rather than a condition in its own right. Primary hypertension, the common form in humans with no underlying cause, is rare in dogs. So a high reading isn’t really the diagnosis. It’s a clue pointing at something else.
What is normal blood pressure for a dog?
Readings come as two numbers: systolic (the pressure when the heart contracts) and diastolic (the pressure between beats). Diastolic is hard to measure reliably in dogs, so your vet will usually work from the systolic figure alone.
The American College of Veterinary Internal Medicine publishes the consensus guidelines most vets work from:
| Systolic reading | Category |
|---|---|
| Under 140 mmHg | Normal |
| 140–159 mmHg | Pre-hypertensive |
| 160–179 mmHg | Hypertensive |
| 180 mmHg and above | Severely hypertensive |
Treatment is generally recommended when systolic pressure stays above 160 mmHg. Below about 90 mmHg in a conscious dog is hypotensive.
Measuring it works much as it does at your GP. A small inflatable cuff goes around your dog’s front leg or tail. It isn’t painful and no sedation is needed. In fact sedatives are avoided, because they alter blood pressure. Your dog may need a small patch of fur clipped so the cuff sits properly against skin.
One high reading doesn’t mean hypertension. Dogs get stressed at the clinic, and stress pushes pressure up. It’s the same “white coat effect” people get, only more pronounced. So your vet will take several readings a few minutes apart in a quiet room, and will often ask you back for a recheck before diagnosing anything. If your vet wants to repeat the test rather than prescribe straight away, that’s good practice.
Dog hypertension (high)
Because it’s nearly always secondary, the causes are other diseases:
- Kidney disease. The most common culprit, and a vicious circle. Damaged kidneys can’t regulate pressure, and high pressure damages them further.
- Cushing’s disease. Excess cortisol raises blood pressure. Studies have found hypertension in well over half of dogs at the point of diagnosis.
- Diabetes. Long-term high blood glucose damages blood vessels.
- Adrenal tumours, which can secrete pressure-raising hormones.
- Long-term steroid medication.
- Age. Older dogs are likelier to have the conditions above.
Obesity gets listed as a cause too, but the evidence in dogs is weaker than you’d expect. Experimental work has found only a small increase, and some measurement methods don’t detect it at all. Keeping your dog trim protects their joints, pancreas and lifespan regardless. See our guides to preventing pet obesity and how much exercise a dog needs.
Dog hypotension (low)
This isn’t a chronic condition to monitor. It’s a sign something acute is going wrong: blood loss from a car accident or dog attack, shock, severe dehydration, heart failure, Addison’s disease, serious infection or heatstroke.
If your dog is weak, collapsing, has pale gums or is breathing rapidly and shallowly, go straight to the vet. Untreated hypotension starves the organs of oxygen. One connection people don’t expect is dental disease, which is linked to heart problems in dogs, and heart problems can lead to hypotension. Our article on pet dental health and heart disease covers that.
Signs of high blood pressure in a dog
In people, high blood pressure sometimes shows as flushed skin. Under a coat of fur, that’s no help to us.
Mostly, dogs show nothing at all until damage has been done. And when signs do appear, they usually belong to the underlying disease rather than the blood pressure. Which is why annual vet checks matter, and matter more as your dog ages.
When hypertension does cause symptoms, they tend to cluster by the organ being damaged.
- Eyes. Sudden or partial blindness, detached retina, bleeding in the eye, permanently dilated pupils. Sudden blindness in an older dog is a classic presentation and needs a same-day vet visit.
- Brain. Head tilting, loss of balance, uncoordinated movement, disorientation, seizures, or a dog that seems flat and withdrawn.
- Heart. A murmur or abnormal rhythm picked up on examination.
- Kidneys. Drinking more, urinating more, or blood in the urine (haematuria).
- Nose. Nosebleeds.
None of these belong to hypertension alone. Any of them is worth a vet visit, and blood pressure is one of the things your vet will check.
Prevention mostly comes down to catching the diseases that cause it. Don’t skip the annual check-up, and consider twice-yearly once your dog is a senior. Ask for a blood pressure reading if your dog has kidney disease, diabetes or Cushing’s, or is on long-term steroids. Act early on small changes too. Drinking more, urinating more, or a dip in energy are all worth a phone call. Well-managed hypertension is compatible with a long, happy life, though the medication is usually lifelong.
When to see your vet urgently
Ring your vet or after-hours clinic straight away if your dog shows sudden vision loss or is bumping into furniture, collapses or goes very weak, has pale gums, has a seizure, has a nosebleed with no obvious injury, or passes blood in their urine.
Dog breeds and blood pressure
You’ll find lists online of breeds “prone to high blood pressure”. Dachshunds, Poodles, Schnauzers and Bichon Frise turn up most often. Treat those lists with some caution. The link is mostly indirect. Some breeds are predisposed to the underlying kidney and endocrine diseases that cause secondary hypertension, but the evidence for a direct breed predisposition is thin.
A more useful question is what your dog’s breed is prone to generally. Dogs New Zealand publishes breed health information, and our guide to hereditary and congenital conditions is a good place to start.
Does PD cover high blood pressure?
Hypertension counts as an illness, not an accident. It’s covered under our Classic and Deluxe plans once the waiting period passes, including where it stems from a hereditary condition. It isn’t covered under Accident, which covers injuries only. Low blood pressure caused by an accident, like a car or a dog attack, is covered on all three.
Pre-existing conditions aren’t covered on any plan. That matters more than usual here, because hypertension mostly turns up in older dogs and our Classic and Deluxe plans have an upper joining age. Wait too long and you may only be eligible for Accident.
Annual limits are $5,000, $10,000 and $20,000. All three plans include third party liability cover, and you can use any registered vet in New Zealand with no co-payments and no lock-in contract.
Get a quote, or read the policy wording for waiting periods, sub-limits and exclusions.