Oh, those adorable puppy-dog eyes — but, sometimes those dilated pupils may not merely be a sign of excitement or curiosity. They could in fact signal an underlying issue that may not have caught your eye.

Let’s explore the different reasons your dog's eyes dilate, what it may mean, and when it’s time to give your emergency vets at VEG ER for Pets a call.

Why are my dog's eyes dilated?

The pupils are the black circular openings in the center of your dog’s eye; the iris is the colored part of the eyes. Similar to a camera aperture, the pupils control the amount of exposure to light. 

When pupil size changes, it can bring in more or less light. For example, when a dog’s pupils are dilated, they appear larger than usual, allowing more light to enter. Let’s take a closer look at the various reasons why this happens.

Normal causes of pupil dilation

First things first: it can be completely normal for your pup’s pupils to change sizes for various reasons, like when your dog is:

• Excited or fearful of something  

• Finding their way around in dimly lit areas 

• Startled by something

Pupil dilation in dogs can be caused by a variety of things. Read on to discover how to monitor your dog and when you should see the emergency vets at VEG ER for Pets, open 247.

When you should be concerned about your dog's dilated pupils

If you notice that your dog is experiencing persistent or uneven pupil dilation (i.e., anisocoria), it can be a sign of an underlying health condition, like an eye condition or neurological issue, which we’ll discuss.

Medical reasons why a dog's eyes can be dilated

Eye injuries or diseases

Dilated pupils in dogs can potentially be a symptom of an injury or ailment. Glaucoma, for instance, increases pressure within the eye, leading to pupil dilation which can be painful for your pooch. 

Other conditions like uveitis (inflammation of the uvea) or retinal diseases can also cause this symptom. If your dog shows signs of discomfort or vision issues along with dilated pupils, it’s time to call your nearest VEG emergency animal hospital ASAP.

Neurological issues causing dilation of pupils

Conditions such as brain tumors, head trauma, or certain infections can disrupt the normal function of your pet’s pupils. Seek emergency veterinary attention right away if you notice the following symptoms alongside dilated pupils:

• Changes in behavior

• Seizures

• Uncoordinated movements  

Behavioral changes and dilated pupils in dogs

Canines showing changes in behavior (e.g., aggressiveness, growling) along with dilated pupils could be experiencing more concerning issues, which we dig into below.

Signs of pain or discomfort

From dental problems to internal injuries — pain can be a result of various issues. Identifying and addressing the source of the pain is vital to your pup’s wellbeing.

See a VEG emergency vet if, alongside pupil dilation, your dog experiences:

• Changes in eating habits

• Limping

• Whining

Just like humans, dogs can experience anxiety and stress. Fear-inducing situations such as thunderstorms or fireworks can temporarily spook your pooch to the point that their eyes dilate. However, if you notice your dog is constantly anxious and shows persistent pupil dilation, it’s important to talk to your primary care vet about how to best manage their anxiety.

How to observe and monitor your dog's symptoms

Keep a close eye on your dog’s eyes and behavior. Try to record any patterns or triggers and share it with your primary care vet.

Monitoring your dog’s eye health

Make sure to always check the condition of your dog's eyes in order to detect issues early. If you notice any of these signs alongside pupil dilation, it’s time to call VEG emegency dog hospital:

• Cloudiness

• Discharge 

• Redness

Documenting canine behavioral patterns

It’s important to record your doggo's behavior and note any signs of pain, anxiety, or unusual behavior. This information can assist your vet in diagnosing any underlying cause of concern.

Schedule routine check-ups 

Make the appointment with your primary care veterinarian, add it to your phone calendar, set an alarm, do whatever you need to do to remember to take that pup to the vet! 

Regular primary care vet check-ups are the best way you can help maintain your dog's eye health and overall well-being. A primary care vet can catch and address medical issues as they arise, before they become emergencies.

During these visits, be sure to bring up any changes you’ve observed in your dog’s eyes or behavior.

VEG emergency animal hospital is open 24 hours every day

If you’ve reached this blog because you’re concerned about your dog’s eyes, take heart that typically, a dog’s dilated pupils are a completely normal response to different stimuli. But, if you notice any persistent or uneven dilation, or dilation is present along with any of the symptoms we’ve discussed above, call us or bring your dog to VEG. 

VEG emergency animal hospitals are here for pet owners 24/7, even on holidays. We’ll triage your dog immediately and provide an unparalleled care experience, while you stay with your dog the entire time. Our top-rated veterinary team will provide the care and support needed to help keep those tails wagging and eyes bright!