Are Black Widow Spiders Dangerous to Dogs?

Dogs are susceptible to the poisonous and potentially fatal venom of the black widow spider (Latrodectus spp.) if bitten. These spiders are found in most states, and only the bite of a female black widow is considered toxic. If you suspect your pup has been bitten by a black widow, get him to the vet right away.


Black Widows

Female black widows are shiny black spiders around a half-inch to 1 inch in size with a red or orange hourglass mark on their abdomens. These spiders bite when they feel threatened, injecting their venom into your pup's skin. The venom contains a potent neurotoxin called alpha-latrotoxin, which causes muscle spasms and paralysis within eight hours of a bite, according to "Clinical Techniques in Small Animal Practice." While the venom is potentially fatal, especially in cats and less so in dogs, with treatment, your pup can recover, but it may take weeks or months.

Recommended Treatment

Veterinary treatment is vital to your pup's survival of a black widow spider bite. Your vet will evaluate your pup's symptoms -- including vomiting, diarrhea, high blood pressure, muscle pain, cramping, incoordination, tremors or paralysis -- and look for a bite mark. She may also perform blood, urine or stool tests. Depending on your pup's condition, she may administer anti-venom to your pup, which is usually only kept in human hospitals, Pet360 reports. She will also provide supportive care including the administration of oxygen, intravenous fluids, pain medication, muscle relaxants and medications to lower the pup's blood pressure, according to PetMD.

By Susan Paretts


About the Author
Based in Las Vegas, Susan Paretts has been writing since 1998. She writes about many subjects including pets, crafts, television, shopping and going green. Her articles, short stories and reviews have appeared in "The Southern California Anthology" and on Epinions. Paretts holds a Master of Professional Writing from the University of Southern California.