If you’ve recently noticed your dog is starting to hesitate on the staircase they’ve climbed a thousand times before or bumping into the living room furniture that hasn’t moved in years, it’s only natural to worry. Your heart sinks a little as you wonder what’s wrong with your best friend.These changes can be subtle at first, but they can be a sign of a larger issue with your dog’s vision. One of the most common causes of this kind of gradual change is a condition called cataracts.In this post, I’ll explore what cataracts are, discuss the many reasons they may develop, and help you identify the signs. Most importantly, I’ll share the information you need to give your dog the best possible quality of life.What Are Cataracts?Let’s start with the basics: what exactly are cataracts? Imagine your dog’s eye is a tiny camera, and inside that camera, there’s a lens that focuses light onto the back of the eye to create an image. In a healthy eye, this lens is perfectly clear and allows light to pass through without any obstruction. A cataract is a clouding of the lens.When looking at your dog, the cloudiness may look like a smudge or fog stretching across the eye and covering your view of the iris. This cloudiness is caused by the proteins in the lens clumping together, which prevents light from passing through properly. As the condition progresses, the cloudiness becomes denser, blocking even more light.In the early stages, the cloudiness will cause your dog’s vision to be blurry. However, if it’s allowed to progress to a more advanced stage, it can lead to complete blindness.Cataracts vs. Nuclear SclerosisIf you have a senior dog whose eyes are starting to show a light haze, it’s easy to jump to the conclusion that it’s a cataract. This is a common concern, but it may be an age-related change called nuclear sclerosis.Nuclear sclerosis is a natural hardening of the lens that happens with age, causing the eye to have a hazy, grayish appearance. Unlike cataracts, it typically doesn’t significantly impact their vision. A cataract, on the other hand, is a more opaque, milky-white clouding that limits the passage of light into the eye. Only a veterinarian can tell for sure which one your dog has.Causes of Cataracts in DogsWhile we often associate cataracts with getting older, there are several reasons your dog may develop them (even at a younger age). Understanding the potential causes can help you take preventative steps and, where prevention isn’t possible, to prepare yourself to give your pup the best possible care.Genetic PredispositionOne of the most common factors, and unfortunately not preventable, is your dog’s genetics. Just like in people, some dogs are simply more prone to developing cataracts due to their breed. Breeds like Poodles, Cocker Spaniels, Golden Retrievers, and Siberian Huskies are all at higher risk. If you know your dog’s lineage, it can give you a heads-up and a reason to be extra vigilant about any changes in their eye health, even from a young age.DiabetesThis is a big one. Diabetes is the most common preventable cause of rapidly developing cataracts in dogs. The link is direct and powerful. When a dog has high blood sugar, it affects the chemical makeup of the eye’s lens. This causes it to swell and become cloudy very quickly.Cataracts are often one of the first signs that a dog is suffering from undiagnosed diabetes. If your vet suspects the clouding is from cataracts, they will almost always test for diabetes as well.Injury or Trauma to the EyeA strike to the head, a scratch, or any kind of physical injury to the eye can cause significant damage to its delicate parts, including the lens. This trauma can impact the proteins within the lens, triggering the formation of a cataract. This is why it’s so important to be careful with your dog around things like sharp sticks and other potential hazards, or to use eye protection (like Rex Specs Goggles) when most at risk. Other Potential Causes While less common, there are other factors that can also contribute to the formation of cataracts. Chronic inflammation inside the eye, a condition known as uveitis, can damage the lens over time. In rare cases, especially in puppies, nutritional deficiencies can play a role, with the lens failing to develop properly. Ultimately, like with people, some cataracts are simply a part of the natural aging process, a gradual change that can happen to any dog as they get older. Warning Signs to Watch Out For Noticing that something might be wrong with your dog’s vision usually starts with subtle changes in their behavior. They can’t tell you that their vision is blurry, but their body language can help communicate that something is happening. Subtle Behavioral Changes These are often the earliest cues. You may notice your once active dog starts to hesitate before jumping onto their favorite spot on the couch or going up and down the stairs. They may seem a little confused, especially in new or dimly lit environments, possibly bumping into furniture or bumping into door frames that they use to navigate without any problems. You may also see a change in their play, as they stop engaging in their favorite games like fetch or struggle to catch treats when tossed their way. Sometimes a dog may become more anxious or clingy when their vision starts to change, especially if they are in an unfamiliar space. Physical Signs of Cataracts in DogsIn addition to behavioral changes, especially as the condition escalates, you may be able to see physical signs in your dog’s eyes. This is why many veterinarians recommend that dog parents do regular eye checks at home, helping them catch subtle changes early. When looking into your dog’s eye, look for a noticeable cloudy, milky-white, or bluish-gray appearance in one or both pupils. One or both pupils may not look as dark or black as they used to. While a hazy look can be a sign of nuclear sclerosis, a dense, opaque white appearance is a stronger indicator of a true cataract.
