Why does my pet have runny eyes?

Symptom: Runny eyes (clear discharge)

Runny or watery eyes are common in pets and can happen for many different reasons. It might be something minor like irritation or allergies, or it could be a sign of an underlying health problem. In this article, we’ll explain what runny eyes can look like, common causes, what you can do at home to help, and when it’s important to seek veterinary attention. 


Written by Dr. Mariella Roberts, Veterinary Surgeon, Animal Trust Vets CIC | Published July 2025 | Review date July 2027 | This advice is for UK pets only and is not a replacement for seeing a vet

Symptom: Runny eyes (clear discharge)

What signs will I notice if my pet has runny eyes? 

Runny eyes in pets, also known as epiphora, can manifest as:  

  • Increase in the amount of tears produced, leading to moisture around the eyes 

  • Tear staining of the fur around the eyes, particularly in light-coloured animals- the stains are often reddish-brown due to the pigment porphyrin in the tears 

What are the common reasons for my pet to have runny eyes?

  • Foreign objects like dust, grass seeds, or even eyelashes can get lodged in the eye 

  • Blocked tear ducts  

  • Scratches, ulcers, or other injuries to the cornea (transparent part of the eye) 

  • Some infections 

DOs - My pet has runny eyes, what to do at home

  • Gently wipe away any discharge from around the eyes 

  • Consider using sterile saline rinse to help flush out irritants and provide temporary relief 

DON’Ts - My pet has runny eyes, what not to do at home

  • Don't use human medications or eye drops 

  • Don't use chemicals to clean in and around the eyes 

  • Don't use your fingers to clean and don't touch the eyeball 

My pet has runny eyes - when should I think about going to the vet?

  • Pain or discomfort such as squinting or rubbing the eye, or the eye being partially closed 

  • Changes in appearance such as redness, cloudiness, swelling or changes size of the pupils      

My pet has runny eyes - when is it an emergency?

  • Any sudden onset of cloudiness, swelling, bloody discharge, pain and vision changes 

  • Foreign objects in the eye 

  • Trauma/injury to the eye or head