Most dogs have extra skin simply because their breed was built that way. Loose, folded skin served working purposes for many breeds over centuries of selective breeding, and it remains a defining physical trait in dozens of popular breeds today. But if your dog’s skin seems looser or more abundant than expected for their breed, or if the change appeared gradually, a medical condition could be the cause.
Breeds Built for Loose Skin
Certain breeds carry extra skin by design. Bloodhounds, Basset Hounds, Shar Peis, Bulldogs, Mastiffs, and Pugs all have loose, wrinkled skin as a standard breed characteristic. This wasn’t accidental. Hunting breeds like Bloodhounds developed extra facial skin that funnels scent particles toward the nose, improving their tracking ability. Breeds historically used for guarding or fighting, like Shar Peis, benefited from loose skin because it made them harder for an opponent to get a firm grip on. Basset Hounds’ drooping skin and long ears work together to stir up ground-level scent while trailing prey.
If your dog is one of these breeds or a mix that includes them, the extra skin is genetic and completely normal. It’s not a sign of a health problem on its own. That said, those folds do require maintenance to stay healthy, which is covered further below.
Hypothyroidism and the “Tragic Face”
When a dog’s thyroid gland doesn’t produce enough hormone, one of the hallmark signs is thickening skin, particularly on the face and head. This creates new folds and a droopy, saggy appearance that veterinarians call a “tragic face” because the dog looks perpetually sad. In a well-documented survey of 162 confirmed hypothyroid dogs, 88% had some kind of skin abnormality.
Other signs tend to accompany this skin thickening. About 40% of hypothyroid dogs lose hair, often starting on the tail (giving it a bare, rat-like look) or around the collar area. Around 22% develop skin infections with a scaly, oily, smelly coat, and 14% have brittle or unusually soft fur that feels more like a puppy coat. Weight gain and low energy are also common. If your dog’s skin seems to be getting looser over time and you’re noticing any of these other changes, hypothyroidism is a strong possibility worth testing for. It’s the most common hormonal imbalance in dogs and is very manageable with daily medication.
Cutaneous Asthenia: A Rare Collagen Disorder
Some dogs have skin that stretches far more than it should because the collagen holding it together is structurally defective. This condition, called cutaneous asthenia (the canine equivalent of Ehlers-Danlos syndrome in humans), is rare but serious. It’s inherited, and dogs are born with it, though owners often don’t notice until the skin starts tearing, sometimes weeks or months after birth.
The core problem is that the collagen fibers in the skin are disorganized and weak. In affected dogs, the skin’s tensile strength drops by roughly 40 times compared to normal. Skin extensibility, measured by gently pulling up a fold along the back, exceeds 14.5% in affected dogs versus much less in healthy ones. The most telling sign is skin that tears easily from minor contact, with lacerations that bleed very little and heal quickly into thin, irregular scars. Over time, affected dogs accumulate multiple scars across their body.
Beyond fragile skin, some dogs with this condition develop joint looseness, hernias, blood-filled swellings under the skin, and occasionally eye problems like cataracts or lens displacement. If your dog’s skin tears with minimal trauma and heals into papery scars, this condition should be investigated. A vet can often make the diagnosis based on the dog’s history and physical exam, though skin biopsies and genetic testing can confirm it.
Dehydration Can Mimic Loose Skin
Sometimes what looks like extra skin is actually skin that has lost its normal elasticity because the dog is dehydrated. Healthy, well-hydrated skin snaps back into place quickly when you gently pinch it. Dehydrated skin stays “tented” for a noticeable moment before slowly settling back down. Research on exercising dogs found that even mild dehydration (less than 1% body weight loss) produced a visually detectable change in how quickly the skin returned to normal position after being tented on the forehead.
This is a quick check you can do at home. Gently lift the skin on the back of your dog’s neck or between the shoulder blades, then let go. If it takes more than a second or two to flatten, your dog may need more water. Keep in mind this test is less reliable in breeds that naturally have very loose skin, since their skin moves differently to begin with.
Skin Fold Problems to Watch For
Extra skin creates warm, moist pockets where bacteria and yeast thrive. Skin fold dermatitis is common in wrinkly breeds, and the deeper the folds, the higher the risk. The condition develops when moisture gets trapped between skin surfaces, creating an environment perfect for microbial overgrowth. A large UK study of affected dogs found that among cases with recorded symptoms, redness appeared in about 34%, general inflammation in 24%, persistent moisture in 21%, bad odor in 19%, and signs of pain in 18%.
Facial folds, tail folds, lip folds, and vulvar folds are the most common trouble spots. You might notice your dog rubbing their face on furniture, a sour or yeasty smell coming from their wrinkles, or reddened, irritated skin when you spread the folds apart. Left untreated, these surface infections can deepen and become quite painful.
Keeping Skin Folds Clean
Prevention comes down to a simple routine: clean between the folds regularly and dry them thoroughly afterward. The PDSA recommends using cotton wool pads soaked in salt water, then making sure no moisture remains in the creases. How often you need to do this depends on your dog. Some wrinkly breeds need daily cleaning of their facial folds, while others do fine with a few times per week. Dogs that drool heavily or have deep lip folds typically need more frequent attention.
Avoid using random household products or human skincare items in your dog’s skin folds. Stick with plain salt water unless your vet has specifically recommended an antimicrobial shampoo or medicated wipe. The goal is to remove trapped moisture and debris without stripping the skin’s natural protective barrier, which can actually make infections more likely.
During your cleaning routine, take a moment to look at the skin inside each fold. Healthy folds should be pink and dry. If you see redness, feel heat, notice an unusual smell, or see a dark discharge, those are early signs of infection that benefit from prompt treatment before they progress.