Why Do Old Dogs Lose Their Toenails?

As dogs age, their toenails become more prone to issues like cracking, infection, and even complete loss. In fact, toenail problems affect a large percentage of senior dogs. According to a recent study, over 20% of dogs develop onychodystrophy, or abnormal toenail growth, by age 8. For senior dogs over the age of 10, the rates are even higher. Toenail issues in older dogs can stem from many causes, ranging from arthritis to hormonal changes. While it may seem like just a cosmetic problem, losing toenails can actually impact your dog’s mobility and comfort. Understanding the common causes of toenail loss in senior dogs is the first step to getting your pup the right treatment.

Anatomy of Dog Toenails

A dog’s toenails are made up of the nail and the quick. The visible part is the nail, also called the claw, which is made up of keratin and continues to grow throughout a dog’s life (LuckyTail, 2023). The nail starts out wider at the base near the toe and tapers to a point at the end. Underneath the hard nail is the quick, which contains nerves and blood vessels that supply nutrients to the nail to help it grow (ToeGrips, 2022). The quick recedes as the nail grows longer.

Dog nails are attached to the end of the bones in a dog’s toes by the nail bed. New nail cells form in the nail matrix at the base of the nail bed as old cells are pushed forward and harden into keratin. This continual growth process is what enables nails to regrow if they break or are trimmed (LuckyTail, 2023). Keeping a dog’s nails trimmed to an appropriate length is important to maintain healthy nail anatomy.

Causes of Toenail Loss

There are several potential causes of toenail loss in senior dogs, including:


Arthritis is common in older dogs and can cause pain and inflammation in the toe joints. This may lead to dogs licking or chewing at their painful toes, resulting in toenail damage or loss (source).


Older dogs are prone to injuries that can damage toenails. Nails may break or tear off after getting caught on surfaces while playing or running (source). Injuries can also lead to infections.


Bacterial or fungal nail bed infections are common causes of toenail loss in senior dogs. They cause inflammation, pain, and eventual nail detachment if left untreated (source).

Hormonal Changes

Hormonal imbalances or thyroid disorders can lead to brittle, cracking nails that are prone to falling off (source).


While rare, tumors of the nail bed or toe can also cause toenail loss in older dogs (source).


Arthritis is a common cause of toenail loss in older dogs. It is a degenerative joint disease that causes inflammation, pain, and stiffness in the joints (https://caninearthritis.org/article/long-toenails-grooming/). As arthritis progresses in the toes, it becomes difficult for the dog to bear weight normally, which can cause the toenails to grow abnormally long.

Long toenails alter the biomechanics of the foot, changing the angles of the joints from the toes up through the leg. This puts more stress on the joints and can actually worsen arthritis pain and inflammation (https://thesilverwoof.com/arthritis-and-toenails). The abnormal pressure on the nails from this improper gait can also cause the nails to weaken and fall off.

Keeping the toenails properly trimmed is essential for managing arthritis and preventing nail loss in aging dogs. Long nails will exacerbate joint problems. Regular nail trims reduce pressure on sore joints and allow the dog to walk more comfortably (https://movebetter.co/animal-treatment/a-dogs-toenail-length-matters/).


Traumatic injuries can damage a dog’s toenails and lead to eventual nail loss as the dog ages. Common injuries that affect toenails include torn or broken nails, nail bed lacerations, and damaged quicks (the blood vessel inside the nail). These injuries are often caused by activities like running, digging, scratching, and playing, especially on rough surfaces.

For example, a dog may tear a nail when playing fetch on concrete or rip a nail off entirely when catching it in carpeting. The force and pressure applied to the nail causes it to either crack or detach from the nail bed.

According to MedVet, broken and torn nails will bleed profusely since they contain a rich blood supply. Severe injuries may require surgery to stitch the torn nail bed. Milder injuries can heal with rest, but they may weaken the nail over time.

As dogs age, damaged nails that have already been weakened by past injuries may eventually fall off due to reduced blood circulation. The accumulated wear and tear takes its toll, preventing proper nail growth. Keeping senior dogs’ nails neatly trimmed can help avoid snagging and tearing of fragile nails.


Bacterial and fungal infections are common causes of toenail loss in senior dogs. These infections often start out minor but can quickly spread and become serious if left untreated. According to PetMD, symptoms of nail infections include discolored nails, swelling, discharge, and sensitivity around the nail bed.

Bacterial infections are usually caused by bacteria entering the nail bed through a crack or cut. Staphylococcus, Streptococcus, and Pseudomonas bacteria are often the culprits. Fungal infections are caused by yeast and mold entering the nail area. These infections cause the nail to thicken, discolor, and crumble away. Foul odor is also common.

If the infection spreads into the nail matrix or bone, it can cause severe lameness, draining lesions, and permanent nail loss. These aggressive infections require antibiotic or antifungal medication from the veterinarian. Topical treatments may also be prescribed. Preventing infections through proper nail trimming and hygiene is key to maintaining healthy nails as dogs age.

Hormonal Changes

As dogs age, their hormone levels start to decline. This natural hormone decline can cause a variety of health issues in senior dogs, including changes and problems with their nails and toenails. One hormone that is particularly important for nail health is estrogen.

Estrogen helps keep nails strong and healthy. As estrogen levels drop in aging female dogs, it can lead to weaker, more brittle nails that are prone to cracking and breaking. Declining estrogen is also associated with several nail conditions:

  • Onycholysis – when the nail separates from the nail bed
  • Onychomadesis – shedding or falling off of the nails
  • Onychodystrophy – malformation and degeneration of the nails

In male dogs, testosterone levels also decline with age. Lower testosterone can contribute to poorer nail quality and increased susceptibility to infections and other nail problems.

Besides hormonal changes, senior dogs may have poorer circulation and slower nail growth. This can lead to nails becoming thickened, brittle, and discolored over time. Problems are often first noticed in the rear legs where circulation is lowest.

If your senior dog is experiencing nail issues, see your veterinarian for an exam and treatment options. Providing nutritional support, keeping nails trimmed, and gently massaging feet and nails can also help improve circulation and nail health.

(Source: https://veterinarypartner.vin.com/doc/?id=9767513&pid=19239)


Cancerous tumors of the toes or nails are relatively uncommon in dogs, but can occur. The most common type is melanoma, which arises from the pigment-producing cells of the nail bed or surrounding skin on the toes (Source). Other cancer types like squamous cell carcinoma and mast cell tumors are also possible, but less frequent.

Signs of nail or toe cancer include nail deformation, nail loss, bleeding, swelling, and licking at the toes. Owners may also notice a dark pigmented mass in the nail bed. These tumors tend to be locally invasive and can damage local structures. They may also spread to other areas of the body.

Diagnosis is made by biopsy of the toe mass. Treatments include surgical removal, radiation therapy, chemotherapy, and amputation in some cases. Even with treatment, the prognosis is guarded if the cancer has spread. But early diagnosis and intervention provide the best chance for recovery.

It’s important for owners to routinely inspect their senior dog’s nails and feet for any abnormalities. Any changes should prompt a veterinary visit for further evaluation. While toe and nail tumors are uncommon, early detection makes a big difference.


If your dog loses a toenail due to injury or infection, there are several at-home treatment options to manage the toenail loss and prevent further issues:

To stop bleeding from a lost or torn nail, apply a styptic pencil, styptic powder, or cornstarch to the nail bed. Hold pressure on the area for 5-10 minutes. This will aid blood clotting. If bleeding persists, see a veterinarian immediately (source).

Keep the nail bed clean by gently rinsing with saline solution or antiseptic wash. Apply antibiotic ointment and wrap in a light bandage. Change bandages daily while healing. This prevents infection and promotes regrowth (source).

Trim surrounding nails to prevent snagging on bedding or floors. File edges smooth. Consider soft nail caps or booties to protect healing nails.

Administer pain medication as recommended by your veterinarian to keep your dog comfortable during healing.

Schedule a recheck appointment to monitor healing progress. X-rays may be needed to check for retained nail fragments if the nail was torn out completely.

With proper care, most dogs recover well from toenail loss. Some nails may regrow partially or fully over several months. Managing pain, preventing infection, and protecting the healing nail bed are the priorities.

Caring for Your Senior Dog

As dogs age, their needs change. Here are some tips for keeping an older dog comfortable:

Keep nails trimmed – Long nails can cause pain and mobility issues. Trim often, every 1-2 weeks if needed. Use a nail grinder for a smooth edge if trimming is stressful. See a groomer or vet if your dog struggles with nail trims. According to Top Dog Health, senior dogs may need more frequent nail trims.

Provide orthopedic beds and ramps – Memory foam beds and ramps can make it easier for arthritic dogs to get up and prevent pressure sores. Use rugs on slick floors.

Maintain a healthy weight – Excess weight strains joints. Work with your vet to determine an optimal weight for your senior dog.

Give joint supplements – Glucosamine, chondroitin, and omega-3 fatty acids support joint health. Consult your vet on dosage.

Adapt exercise – Low-impact exercise like short walks prevents muscle loss. Avoid high-impact activities that could cause injury.

Groom regularly – Helps circulate blood and skin health. Massage can also improve joint mobility.

Provide proper nutrition – Quality senior dog foods address changing nutritional needs. Feed omega-3 rich foods like fish.

Schedule more vet visits – Senior dogs need visits every 6 months to monitor health issues like arthritis, cancer, or organ function.

With some extra care and attention, you can ensure your senior dog stays happy and comfortable through their golden years!

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