Noticing your dog losing hair on their legs can be worrying, especially when the skin looks irritated, flaky, or unusually smooth beneath the thinning patches.
Leg hair loss is commonly linked to allergies, parasites, infections, hormonal issues, or excessive licking — and the exact pattern of hair loss often gives important clues about the underlying cause.
We outline the common causes of hair loss on a dog’s legs, what you can do at home, and when to seek veterinary help.
Dog Losing Hair on Legs — Why It Happens
Dogs lose hair on their legs when the skin becomes inflamed or irritated from allergies, parasites, infections, hormonal disorders, or over-licking. Some dogs develop patchy bald spots, while others show smooth, symmetrical thinning on both legs.
Because dogs frequently use their legs for scratching, grooming, and daily movement, this region experiences constant friction, licking, and environmental exposure. When irritation or inflammation develops, hair loss often appears first on the front or hind legs.
But internal medical conditions can also cause slow, progressive hair loss without any itching or redness.
Dog Losing Hair on Legs: Common Causes
Environmental Allergies
Environmental allergies are one of the top reasons dogs lose hair on their legs. Allergens like grass, pollen, mold spores, or household dust mites irritate the skin and create chronic itching.
Dogs often chew or lick the lower legs, wrist areas, or thighs because these areas are easy to reach.
This repeated licking damages the hair follicles, causing hair to fall out or break off. Over time, the skin may appear red, flaky, or slightly thickened.
Seasonal patterns also appear — symptoms often worsen in spring or fall depending on local allergens. If your dog also licks their paws or rubs their face, allergies become even more likely.
Read more: Dog Losing Hair in Patches and Scabs (What it means)
Fleas or Flea Allergy Dermatitis
Flea allergy dermatitis (FAD) causes intense itching, even from a single flea bite. Dogs often react by biting and chewing their legs, tail base, and belly, which leads to bald patches, scabs, or red, irritated skin.
The tricky part: many owners never see a flea. Dogs chew them off quickly.
Hair loss on the legs from fleas may appear as:
• small bald patches on the thighs
• red bumps or scabs near the lower legs
• thinning fur along the inner legs from chewing
If the itching seems severe or sudden, always consider fleas — even if your home is clean and your dog goes outside briefly.
Food Allergies
Food allergies create ongoing skin inflammation that leads to constant licking and chewing, especially on the legs and paws. Dogs may develop hair loss around the ankles, wrists, or thighs due to the chronic irritation.
Common triggers include:
• Chicken
• Beef
• Eggs
• Dairy
• Wheat
• Soy
Because food allergies persist year-round, owners often notice no seasonal break. Symptoms also commonly include ear infections, digestive changes, or itchy skin around the face.
Mange
Mange can cause patchy or widespread hair loss on the legs, depending on the type.
Demodectic Mange (Demodex)
• Causes circular, smooth bald patches
• Often shows up on legs, face, and trunk
• More common in puppies or dogs with weak immune systems
Sarcoptic Mange (Scabies)
• Extremely itchy
• Can cause rapid hair loss on legs, chest, belly
• Highly contagious to other pets and humans
Both forms cause redness, scaling, and discomfort. Dogs often bite and scratch the legs aggressively, accelerating the hair loss.
Hormonal Disorders
Hormonal issues cause a unique type of leg hair loss: smooth, symmetrical thinning without itching. The hair falls out gradually, and regrowth becomes slow or absent.
Two common culprits include:
Hypothyroidism
• Causes thinning on legs, tail, and trunk.
• Skin becomes dry and flaky.
• Dogs may gain weight or appear sluggish.
Cushing’s Disease
• Causes hair thinning on legs, belly, and flanks.
• Dogs may develop a pot-bellied appearance.
• Skin becomes fragile or easily bruised.
If leg hair loss occurs without scratching or redness, hormonal disease becomes more likely.
Related: Dog losing hair in patches on back (Here’s why)
Bacterial or Yeast Skin Infections
Skin infections often develop when the skin barrier is compromised by allergies, moisture, parasites, or over-licking. These infections commonly appear on the legs because:
• dogs lick the legs frequently
• moisture gets trapped in long fur
• minor scratches from running or walking can introduce bacteria
Signs include redness, odor, scabs, oozing, darkened skin, or greasy patches. Hair falls out or breaks easily in the affected areas. Without treatment, infections may spread up the legs or into other parts of the body.
Over-Licking From Pain, Anxiety, or Compulsion
One of the most overlooked causes of leg hair loss is excessive licking due to pain, boredom, or anxiety. Dogs may lick the legs compulsively when:
• arthritis causes leg discomfort
• stress triggers repetitive behaviors
• boredom leads to over-grooming
• nerve pain or tingling occurs in the legs
Over time, the licking produces bald spots, darkened skin, thickened areas, or moist sores known as lick granulomas. These can be slow to heal and often require veterinary care.
Read more: Dog Losing Hair and Itching (Underlying causes explained)
What to Do If Your Dog Is Losing Hair on Their Legs
Start by gently examining the skin. Look for redness, bumps, scabs, flakes, or signs of chewing. If your dog reacts strongly when you touch the area, pain or infection may be present.
Because fleas are so common, ensure that your dog is on a reliable, vet-recommended flea prevention. Even indoor dogs benefit from consistent monthly protection.
If allergies are suspected, consider reducing exposure to potential triggers. Wiping your dog’s legs and paws after outdoor walks can remove pollen and other irritants. Bathing with a gentle, hypoallergenic shampoo may soothe inflammation and improve comfort.
Avoid harsh cleaners, scented detergents, or rough bedding that may irritate the skin. Try redirecting excessive licking by offering chew toys, enrichment, or supervised distraction — but don’t use punishment or bitter sprays, as these may increase stress.
If symptoms are widespread, persistent, or worsening, a veterinary appointment is important to identify the root cause.
When to Call or Visit Your Vet
Seek veterinary care if:
• Hair loss is rapidly spreading.
• The legs show redness, infection, scabs, or bleeding.
• Your dog is extremely itchy or uncomfortable.
• Hair loss looks symmetrical.
• You suspect mange or flea allergy dermatitis.
• Your dog shows signs of hormonal disease (weight gain, lethargy, belly swelling).
The legs are prone to irritation and infection, so treating the underlying cause early helps prevent discomfort and long-term skin issues.
Read more: Dog shedding excessively (What’s causing it?)
Key Takeaway
When a dog loses hair on their legs, the most common causes include allergies, parasites, infections, hormonal disorders, or excessive licking.
Paying attention to the pattern and symptoms surrounding the hair loss helps narrow down the cause quickly.
With proper diagnosis and treatment, most dogs experience relief and healthy hair regrowth. Early care makes a big difference, especially if discomfort or infection is present.