Single Eye Dilation

by Mary
(Renton, Wa, USA)



Anyone ideas as to why my puppies eye will dilate like the picture shown? It doesn't seem to occur with any kind of regularity or cause. He's 18 weeks and this has happened 5 times since we've had him. It usually resolves on its own after an hour or so.

Any information would be most appreciated!

Comments for Single Eye Dilation

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Anisocoria in Dogs
by: jcrply

If you will GOOGLE the phrase "Anisocoria in Dogs", you will find lots of information about it and lots of photographs. There are serious causes and not-so-serious causes of this condition. I hope your pup's is one of the not-so-serious!

Grown out of it
by: Anonymous

Wanted to follow up and say that he seems to grown out of it and doesn't have any long lasting effects!

News about this puppy?
by: Elly

Hi :)
Can I know how continued life of this puppy, and if there are any useful info?

Thank you very much

Intermittent Anisocoria
by: Tara

Hello, we have a 5 month old blue merle, blue eyed boy who also has had one pupil shrink 3x in the last month. The pupil that shrinks is not always the same eye. It too resolves within ~1hr. Any other insights as to what might cause this? Did you follow up with any specific medical procedures? We have a vet appt to address this in a few days.


Response to Ellie
by: Anonymous

Rudy is almost 3 years now and he hasn't had an incident in a long time. He seems to be normal with all of the personality traits of any other Aussie that I've read about. He's an awesome companion and my 4 legged fur baby. :-)

Response to Tara
by: Anonymous

My vet recommended a "wait and see" policy to see if it happened on a regular basis or got worse. He told me that this is sometimes something that can happen and they can grow out of it.

Luckily, thats what happened with him so we didn't do any medical procedures. It always happened with the same eye so we will still watch for it. He is 3 years old now and it didn't seem to have any lasting effect.

Hope it is the same case for you and your pup!

Aussie eyes
by: Vicky

We have an 8 month old Aussie. She bumped her head and we noticed her pupils being very uneven, rushed her to the vet and by the time we were ready to leave they were back to normal with no real answers. It happened again last night, out of nowhere. No bump or any obvious reason for it to happen. It went back to normal within 20 minutes. What is the most common cause of this in Aussies and if I take her back to the vet, what should I focus on. I don't have thousands to do MRI's and stuff like that.

anisocoria in blue merle
by: David

We observed this in our 1.3 yr old blue merle yesterday evening, inducing several frantic minutes of worrying and googling, which resulted in us finding some scary information as well as this site. She seemed otherwise completely normal, and thankfully her pupils are much better matched today. We are still considering taking her to a vet to be on the safe side.

Same issue for my Aussie
by: Anonymous

My Aussie had the same issue with her left eye when she was a puppy. Her left pupil was nearly pinpoint in size and her other was normal. She acted as if she didn’t notice at all and was totally fine. It happened once more within her being a year old and I figured she grew out of it like many people say will happen. She is now 4 and just had the same issue again today.

Does anyone have any idea what’s causing this? Or any suggestions on how to treat this? I’m trying to avoid spending hundreds of dollars on MRI and vet bills if possible.

It’s an Aussie thing
by: Joshua B

Red merle here. He’s a male. same thing as others. Transient anisicoria. occurred 4-5 times. He’s now 7.5 months. Obviously googled this and got here. Vet says same thing. watch and edit. seems to have grown out of it. last time about a month ago after he got neutered. All I can say is "it must be an Aussie thing". We have no other explanation. Never seemed to bother him. Lasted no more than an hour or two. I always worry he could start seizing and has a brain tumor or something. so far so good. Glad to know he’s not the only one. probably benign.

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