According to Britannica, there are more than 43,000 different species of spiders found in the world. You notice a spider bite on a dog. What should you do?

With only a tiny percentage being considered dangerous (albeit deadly to both dogs and humans).

How difficult a spider is varies when considering dog anatomy versus human anatomy.

Generally, spider venom is designed to be efficient against smaller animals, like cats or dogs.

Some spiders cannot bite dogs as their mouths are too small to penetrate the skin.

This prevents deadly envenomations (the process in which venom is injected) when bitten. Other spiders are toxic to dogs and can successfully kill your pet.

Four particularly dangerous spiders can be found in the United States one way or another: Black Widow, Brown Widow, Brown Recluse, and Tarantulas.

Here's what they look like:

Most Dangerous Spiders to Dogs (in the USA)

 Spider Bite on a Dog

Signs of a Spider Bite on Dogs

The species of the spider determines the symptoms shown by the dog after they've been bitten.

If the spider bite was from a black widow spider, the dog might develop signs within 8 hours.

This does not mean that they need to visit the clinic. Spider's bite varies by a few degrees, with some bites being “dry bites” (bites that do not contain venom).

Symptoms consist of slight pain along with redness and swelling at the site of the bite.

If the spider released a damaging amount of venom into the dog, symptoms would include cramping, muscle pain, diarrhea, tremors, agitation, and vomiting.

Then, for example, if a brown recluse spider bites, the dog may not initially show signs of pain. A small amount of redness may be noticeable, along with a blister developing within 2-8 hours.

It may also develop into a blister with a bulls-eye lesion, a red circle surrounding the pale area where the bite occurred. This is a sign that a damaging portion of venom was released.

Most spider bites on dogs will show signs of irritation, pain, redness, and swelling.

Others will exhibit more severe fever, weakness, muscle or joint pain, puss, weak pulse, increased heart rate, lethargy, trouble walking or standing, vomiting, drooling, and diarrhea.

A spider bite on a dog may be hard to identify as noticing the bite site is challenging through the fur.

Dogs may sometimes yelp, become anxious, or whine and lick excessively at the bite.

Looking out for advanced symptoms to determine the significance of the spider bite will allow you to take the proper precautions and actions.

What Are the Symptoms of Spider Bites on a Dog?

If your pup receives a bite from a venomous spider, then he will likely show some signs and symptoms. These can include weakness, fever, joint pain, muscle pain, swelling, pus, redness, seizures, or a weak pulse.

If your dog is bitten by a venomous brown recluse spider or black widow spider, more severe symptoms can arise without treatment.

Simply put, the neurotoxin can spread and make things worse. Your dog may experience severe pain in his abdomen, chest, or back. He may experience rigid muscles, lack of coordination, high blood pressure, or an increased heart rate.

In severe cases, abdominal muscle paralysis can lead to respiratory collapse. Seizures and death are also possible.

If you notice these symptoms, then take your dog to the vet. Let him know that you suspect your dog interacted with venomous spiders.

How Do You Treat a Spider Bite on a Dog?

Whether your dog's bite is from a brown recluse, black widow, or another type of spider, the basic steps are the same.

Start by looking to see if the spider left a stinger in the wound. If so, go ahead and remove it. It would help if you grabbed a cold compress to reduce swelling by the bite. Other home remedies include oatmeal baths and aloe vera.

You can also make a paste with water and baking soda, then apply it to the wound.

If you suspect the bite is from a poisonous spider, then contact your vet. You should also contact the vet if you notice severe signs.

If your dog doesn't seem to have any adverse reaction to the bite and you don't think the spider was venomous, you can wait to contact the vet.

However, pet owners who wait to contact the vet should still keep a very close eye on their dog. You never know when mild redness will advance, and you'll be dealing with severe cases.

5 Home Remedies of Spider Bites

Every spider and spider bite is different, allowing for other actions to be taken.

The severity of the bite will depend on the proper course of action, whether you can deal with the edge at home or if a vet visit is necessary.

There are five main courses of action for dealing with spider bites:

1. Basic Treatment

Most spider bites do not require medical intervention or extensive treatment, and they can be treated by a simple step-by-step method at home.

First, wash the spider bite area on your dog with soap and water or dog shampoo. Then use a cold compress on the bite area.

Repeat for the next couple of days, as necessary. You should not require pain medications unless the dog shows severe symptoms.

2. Potato Poultice

A simple potato may assist in reducing the inflammation and reaction to the spider bite on the dog.

Create a potato poultice by grating a peeled potato and putting the shreds into a thin piece of cloth. Using a rubber band, secure the potato pieces inside the fabric and apply the poultice to the spider bite until the potato is dry.

Repeat as needed, making sure to clean the bite before attempting to use the poultice again.

3. Baking Soda Paste

Another cost-effective solution, because applying baking soda paste, was shown to heal a spider bite.

Make the paste out of baking soda and water and apply it several times a day to improve the spider bite symptoms. For a thick paste, use three parts baking soda and one part water.

4. Aloe Vera

Farnam Aloe Heal Aloe Vera Veterinary Cream for use on Horses and Dogs 4 Ounces Aloe vera, known for its skin-reviving properties, is another option for healing a spider bite on dogs. It can reduce inflammation and itchiness, too. Please do not use the gel from a natural aloe vera plant, as a dog can likely ingest it and get sick.

Search for a product labeled as dog-friendly, such as an aloe mist or an ointment that contains aloe.

This one from Farnam is a good option. You can apply aloe vera several times a day until the spider bite shows improvement or heals.

5. Vet Visitation

If a spider bite on the dog has not healed or is showing advanced symptoms, it is time to visit the vet to determine the next course of action.

Some spiders contain venom that needs to be treated with antivenin.

Always try to capture the spider that may have bitten the dog, take a picture, or contain the spider in a safe place so that it can be adequately identified when a vet visit is needed.

Vet Care of Spider Bite on Dogs

If the spider bite requires veterinary care, the healing process can still take anywhere from several days to several weeks and even several months.

If there is antivenin available, the vet will give it intravenously to the dog, and envenomation typically resolves within 30 minutes.

There is a risk of an allergic reaction in the pet that the vet generally counteracts by giving them medication.

If antivenin is not available, the veterinarian will treat the dog with pain medications and muscle relaxers to control the reaction. Supportive care may also be used, such as IV fluid.

Severity Of The Spider Bite

While most spider bites are harmless to dogs or close to safe where you don't have to worry, some are very dangerous and deadly to dogs.

Never assume that the dog is past the danger period until the spider bite has completely disappeared and the dog is free of any symptoms.

Emergencies can arise and need to be watched out for. When a bite is left untreated, it can lead to the skin dying and ulcerating, large wounds that are slow to heal, and risk of infection, seizures, blood disorders, kidney failure, and death.

Common Questions about Spider Bite on Dogs

Even with all of the above information, you may still question how spider bites affect your canine companion.

The following FAQ should help clarify everything from treating spider bites to when pet owners need to worry about potentially venomous spider bites.

Can a Spider Bite Kill a Dog?

You don't typically have to worry about a spider doing severe harm to your dog.

Because spiders don't actively hunt your pets, any bites will typically be accidental. But that doesn't mean you never have to worry if a spider bites your dog.

That is because some spiders are indeed venomous enough to kill dogs. Others may cause serious harm.

The good news is that even if your dog gets bitten by a venomous spider, he has a perfect chance of survival.

The key to that survival is getting the anti-venom on time. This can be a death sentence if you ignore clinical signs and rely on natural remedies at home instead of visiting the vet.

That is why it is always essential to bring your dog to the vet after a bite the second you suspect side effects from the spider bite.

You want your dog to get treatment before he experiences more severe signs.

Can You Give a Dog Benadryl for a Spider Bite?

Yes, you can give your dog Benadryl after a brown recluse spider bite or a bite from another spider.

Remember that Benadryl will reduce itching and swelling thanks to being an antihistamine.

It will not stop the venom from hurting your dog. It can also make your dog tired. Please don't give your dog more than a milligram of Benadryl for each pound he weighs.

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Spider Bite on a Dog

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Shelly lives in Iowa with her husband and Australian Shepherd named Tex. She's been an animal lover since she was a child. Currently, she enjoys reading and writing about dogs, and spending time with her family and getting involved in all things pets.