Skin Allergies or Bug Bites: What Does My Dog Have?

If your dog is scratching themselves more often than normal and you notice a rash or bump on their skin, it’s time to investigate the source of the itching. Symptoms related to itching could mean a variety of underlying issues, such as skin allergies, flea infestation, external parasites like fleas and mites, skin infections, or even skin cancer.

It's important to identify the cause of the scratching or bumps with the help of a veterinarian. Once you know what's going on, your vet can start treatment immediately.

Types of Skin Allergies in Dogs

The most common types of skin allergies in dogs are:

Flea Allergy Dermatitis (FAD)

Dogs with FAD are hypersensitive to flea saliva, and even a single flea bite can trigger intense itching and skin irritation. All dogs are essentially allergic to fleas, so staying proactive on flea control preventative medication is critical to a dog’s health.

Food Allergies

Certain proteins like chicken, beef, and pork in your dog's diet can cause an allergic reaction, resulting in skin problems such as itching, redness, and a rash. Your vet can help determine the source of the food allergy and recommend a food prescription diet.

Atopic Dermatitis

Also known as environmental allergies, atopic dermatitis is caused by an allergic reaction to triggers like plant pollen, dust mites, mold spores, or other environmental allergens. The most common symptom is profound itchiness of the face, ears, paws, armpits, and abdomen.

Contact Dermatitis

A contact dermatitis allergy occurs when your dog's skin comes into direct contact with irritants like certain plants, chemicals, or certain materials, leading to localized itching and inflammation. Eliminating the allergen source will usually resolve skin allergy symptoms.

What Do Skin Allergies Look Like on Dogs?

When dogs have skin allergies, pet parents may notice various symptoms, including:

• Excessive scratching—Dogs with allergies often scratch themselves excessively, especially in areas like the armpits, belly, and rump.

• Redness and inflammation—Allergic reactions can cause the skin to become red, inflamed, and visibly irritated.

• Bumps—Raised bumps or hives may develop on the dog's skin, resembling mosquito bites. These can be small, red, itchy spots or pimples that may be scattered across the body.

• Hair loss—–Excessive scratching and chewing can lead to hair loss or thinning of the coat in specific areas. Bald patches or uneven fur growth might also be noticeable.

• Sores and hot spots—Dogs may develop sores or hot spots, which are inflamed and infected areas of the skin. These can be moist, red, and painful, often accompanied by oozing of pus or crusting.

• Itchy ears—Ear infections can cause your dog’s ears to be red and itchy. You may notice yellow, tan, or brown discharge in their ear canals.

Symptoms of Skin Allergies on Dogs

In addition to physical symptoms, behavioral signs could indicate a skin allergy issue, including:

• Constant licking or chewing, particularly the ears, paws, and rear end.

• Rubbing themselves against furniture, carpet, or other surfaces to relieve itching and irritation.

• Frequently changing positions, pacing around due to discomfort, or having difficulty sleeping.

• Becoming irritable or exhibiting signs of aggression, such as yelping or growling, when a sensitive area is touched.

While skin allergies are one potential cause of excessive itching in dogs, it’s important to determine if a bug bite is actually the culprit.

Types of Bug Bites on Dogs

The most common types of bug bites on dogs include the following. 

Fleas

Fleas are a common external parasite that can bite dogs and cause itchy, red bumps. Dogs with flea infestations may exhibit excessive scratching, hair loss, and inflamed skin.

Ticks

Ticks will attach themselves to a dog's skin and feed on their blood. Tick bites can be identified as small, raised bumps, and the tick may still be attached to the skin.

Mosquitoes

Mosquitoes can bite dogs, causing small, itchy bumps similar to mosquito bites on humans. Dogs may scratch or bite at the affected areas. Mosquito bites can also transmit diseases such as heartworm disease, which is why heartworm preventative medication is so important.

Ant Bites

Ant bites may result in bright red papules on the skin that can cause itchiness. They are usually found on the belly or on the inside areas of the rear legs.

Spider Bites

Spider bites, depending on the type of spider, can affect dogs, leading to localized swelling, redness, and pain.

Mites

Mites such as sarcoptic and demodex mites can result in red, scaly, and crusty patches of skin, along with hair loss.

Other Insects

Stings by bees, hornets, or wasps usually result in localized swelling, redness, and pain at the site of the sting.

What Do Bug Bites Look Like on Dogs?

Bug bites on dogs can vary in appearance, but general characteristics may look like:

• Raised bumps—The size and color of the bumps can vary depending on the type of bug and the dog's individual reaction. They may be small, red, or slightly swollen.

• Small red dots or clusters—Usually found where the bugs tend to bite, such as the abdomen, groin, or armpits.

• A raised, circular rash—In some cases, this can mean a tick bite. It can show up within 30 days of the bite. In other cases, a tick bite will not leave a lesion.

While bug bites and allergies can share some similarities in terms of itching and redness, there are a few differences to consider:

• Allergic reactions tend to be more generalized, affecting larger areas of the body, but bug bites are often localized to the site of the bite.

• Allergies can have a more widespread impact on the dog's skin, causing rashes, hives, or other allergic dermatitis symptoms. Bug bites, on the other hand, usually result in smaller, distinct bumps at the bite locations.

• Allergies can be triggered by various allergens, such as pollen, dust mites, or certain foods, while bug bites are caused by insects or spider bites.

Symptoms of Bug Bites on Dogs

Insect bite reactions can range from mild to severe and include:

• Itching and local inflammation

• Hives

• Swelling of the ears, eyelids, or muzzle

• Pale gums

• Vomiting

• Diarrhea

• Difficulty breathing

• Collapse

Additional behavior and symptoms may include a dog becoming restless and agitated due to the discomfort and itching caused by the bites. They may struggle to find a comfortable position and may appear more anxious or irritable than usual. Dogs may also excessively lick or bite at the affected areas to relieve itching and discomfort caused by bug bites. This behavior can lead to further skin irritation and potential secondary infections.

Treatment of Skin Allergies and Bug Bites on Dogs

Skin allergies in dogs typically require a trip to your veterinarian. Your vet will do a thorough examination of your dog, paying particular attention to their skin and hair coat. They will also take a sample of fur and material on the surface of the skin to examine under a microscope.

Allergy testing can identify the specific allergens causing the reaction. This can be done through blood or skin tests to determine what is triggering your dog's skin allergies. Once a diagnosis is confirmed, a treatment plan may include medications (antihistamines, steroids), medicated shampoos, topical sprays, dietary changes like a prescription diet, or immunotherapy (allergy shots).

Typically, minor bug bites can be managed at home, following these steps:

• Gently clean the affected area with mild soap and water to remove any dirt or debris.

• If there is swelling or inflammation, a cold compress (a clean cloth soaked in cold water) can help decrease swelling and soothe the area for 5–10 minutes at a time.

• Putting on an Elizabethan collar to prevent licking or biting at their skin.

• With bee or wasp stings, an oral antihistamine like Benadryl can usually be given after you have talked with your veterinarian.

If the bug bite causes severe symptoms, such as excessive swelling, difficulty breathing, or signs of an allergic reaction, immediate veterinary attention is necessary.

While over-the-counter (OTC) products like topical creams or ointments may provide some relief for bug bites, it's best to consult with a veterinarian before using them. Some ingredients, like lidocaine and zinc oxide, can be toxic to dogs if ingested, or they may not be suitable for specific situations.

Keeping Your Dog Itch-Free

To keep your dog itch-free, there are several preventative measures you can follow:

• Regularly groom your dog. Bathing and brushing their coat can help prevent matting and remove loose fur.

• Provide your dog with a balanced and nutritious diet to support their overall immune system and skin health. Research suggests that omega 3 fatty acids (from fish oil) are beneficial to a dog’s skin and coat.

• Use veterinarian-approved flea and tick prevention products like spot-on treatments, oral medications, and flea collars. Regularly check your dog for fleas and ticks, especially during peak seasons.

• Regularly vacuum carpets, wash bedding, and treat indoor and outdoor areas with pet-safe insecticides.

• Managing your dog’s allergies may involve dietary changes, using hypoallergenic bedding, minimizing exposure to specific environmental triggers, or considering allergy shots (immunotherapy).

• Limit your dog's outdoor time during peak activity periods, such as dawn and dusk, when mosquitoes are more prevalent. Avoiding areas with high insect populations, tall grass, or stagnant water can also help reduce the chances of bug bites.