My dog keeps sneezing: what might my vet investigate?

Is it a sneeze or a 'reverse sneeze'?

A normal sneeze pushes air out through the nose. It helps clear dust, pollen or other irritants and is usually nothing to worry about if it happens now and again.

A reverse sneeze looks and sounds quite different: your dog may stand still, stretch their neck and make a loud snorting or honking sound as they pull air in quickly. Episodes usually pass within a minute. Reverse sneezing is common and often harmless, but it can be alarming the first time you see it.

Why might a dog keep sneezing?

The nose is lined with delicate tissue that reacts quickly to anything unusual. Many different problems can cause sneezing, and some are much more common than others. Possible causes include:

• Irritants such as dust, smoke, strong scents or pollen
• Something stuck in the nose — in the UK, grass seeds (awns) are a well-known example in summer
• Infections, which may be viral, bacterial or fungal
• Inflammation of the nasal lining, sometimes linked to allergies or to longer-term 'rhinitis' (inflammation inside the nose)
• Dental disease, as the roots of some upper teeth sit very close to the nasal passages
• Nasal mites, which are uncommon
• Growths inside the nose, which are less common and more likely in older dogs

What your vet may do first

Your vet will usually start by asking questions. How long has the sneezing been going on? Is it getting worse? Is there discharge from one side or both? Has your dog been somewhere grassy recently? Any change in appetite, energy or breathing?

They will then examine your dog — looking at the face and nose, checking airflow through each nostril, looking in the mouth and at the teeth, feeling the lymph nodes under the jaw and listening to the chest.

For many dogs, this is enough to decide on a sensible next step. That might be treatment, a period of monitoring with a planned check-up, or further tests. There isn't a single 'correct' route — it depends on your dog and what the examination shows.

Tests your vet might consider

If sneezing persists, or there are signs such as one-sided discharge, nosebleeds or facial swelling, your vet may suggest investigations. These are chosen to answer specific questions, so not every dog needs every test.

Blood tests

Check general health before an anaesthetic. If there are nosebleeds, tests of blood clotting and blood pressure may also be suggested.

Mouth and dental examination

A thorough look at the teeth and gums, often under anaesthetic, to check for dental causes.

X-rays

Can show some changes in the nose and teeth, but the overlapping bones of the skull make fine detail hard to see.

CT scan

Builds a detailed, three-dimensional picture of the nose, sinuses and surrounding bone. Usually needs a general anaesthetic or heavy sedation.

Rhinoscopy

A camera examination of the inside of the nose under general anaesthetic. It allows the vet to look directly, remove some foreign objects and take samples.

Samples for the laboratory

Small tissue samples (biopsies) or swabs can help identify inflammation, infection or a growth.

Why a camera examination isn't always the first step

Rhinoscopy can be very helpful, but it needs a general anaesthetic and it isn't needed for every sneezing dog. Many dogs improve with simpler measures, or the cause becomes clear from the history and examination.

When further investigation is recommended, imaging such as CT is often carried out before rhinoscopy — usually during the same anaesthetic. This is because taking samples can cause some bleeding, which could make the scan harder to interpret.