Quick Answers
If a dog eats a venomous spider, the potential consequences depend on the type and amount of venom the spider carries. Some reactions can include:
– Pain and inflammation at the bite site
– Muscle tremors and stiffness
– Excessive drooling and panting
– Difficulty breathing
– Vomiting, diarrhea, loss of appetite
– Increased heart rate and blood pressure
– Disorientation and lethargy
– Paralysis
– Death (in rare cases or with very venomous spiders)
The severity of symptoms often depends on the size and health of the dog. Smaller dogs are at higher risk of serious complications. Immediate veterinary treatment is vital to counteract the venom and support the dog through any toxic effects. With prompt care, most dogs recover fully.
Identifying Venomous Spiders That Dogs May Encounter
Not all spiders are venomous to dogs. Some of the most dangerous spider species dogs may come across include:
– Black widow – Neurotoxic venom can cause muscle spasms, abdominal pain, lethargy.
– Brown recluse – Cytotoxic venom breaks down cells and tissues, causing lesions and necrosis at the bite site.
– Brown widow – Venom similar to black widows that affects neurotransmitters.
– Hobo spider – Mildly venomous but can provoke severe reactions in some animals.
– Redback spider – Australian relative of black widows, with similarly potent neurotoxic venom.
– Brazilian wandering spider – Venom is a powerful neurotoxin causing paralysis.
Appearance and Habitats of Venomous Spiders
Many venomous spiders have distinct markings to help identify them:
– Black widows – Shiny black body with red hourglass shape on the underside. Found in wood piles, trash, and undisturbed corners and crevices.
– Brown recluse – Brown with violin-shaped marking on top. Inhabits crawl spaces, cellars, sheds, garages.
– Brown widow – Brown with banded legs and orange-yellow hourglass. Found in yard debris, flower pots, outdoor furniture.
– Hobo spider – Brown body, long legs. Lives in cool, dark places like basements and outbuildings.
– Redback – Glossy black with red stripe on abdomen. Common in Australia under logs, in rubble piles.
– Brazilian wandering spider – Hairy brown body, long legs. Found hiding in banana clusters and other vegetation.
If you suspect your dog encountered a venomous spider, try to collect the specimen for identification. But seek prompt veterinary care regardless, as some venomous spider bites may appear relatively benign at first then rapidly worsen.
Signs of Spider Bite Envenomation
The effects of a venomous spider bite can begin setting in within 15-60 minutes after the encounter. Some early signs to watch for include:
– Visible fang marks, localized swelling and redness at bite site
– Intense itching and discomfort around the bite
– Excessive drooling and hyperventilation
– Whining, crying and signs of pain
– Muscle twitching, tremors, stiffness
– Difficulty walking or standing up
– Decreased energy, lethargy, weakness
These can progress to:
– Vomiting, diarrhea, loss of appetite
– Increased body temperature and heart rate
– Disorientation, unsteadiness, dilated pupils
– Partial paralysis
– Seizures and unconsciousness (rarely)
Bites from more toxic spiders like the black widow can also cause abdominal pain, rigid muscles, high blood pressure. Brown recluse bites take longer to show effects but can lead to tissue death and necrosis. Seek immediate vet attention if a known venomous spider bite occurs.
First Aid for Spider Bites
While on route to the vet clinic, the first steps for suspected spider envenomation include:
– Try to identify/collect the spider if possible, but focus on getting to the vet as the priority
– Gently wash the bite area with soap and water if possible
– Apply a cool compress to bite site to reduce swelling and pain
– Keep the dog quiet and calm to slow venom absorption
– Monitor breathing and signs of shock
– Call animal poison control for guidance if needed
Do NOT:
– Apply a tourniquet or tight wrapping that can cut off circulation
– Apply heat to the bite
– Make any incisions at the bite site
Timeliness is key – the faster antivenin can be administered, the better the outcome. Don’t wait to see if mild symptoms resolve on their own.
Diagnosis and Treatment
At the vet’s office, they will examine the dog for signs of envenomation and may run tests such as:
– Complete blood count to check for abnormalities indicating toxin presence
– Biochemical blood profile to assess kidney and liver function
– Urinalysis for muscle breakdown products
– Coagulation testing for potential bleeding disorders
– Arterial blood gases to determine oxygenation
Treatment depends on the type of spider, severity of symptoms, and dog’s overall health. It may include:
– Pain medication and muscle relaxants for stiffness and cramping
– Antivenin or antidote, if available for the particular spider venom
– IV fluids and electrolytes for dehydration
– Antihistamines, steroids, epinephrine to counter allergic response
– Topical antibiotics if bite site becomes infected
– Wound care if necrosis occurs at the bite
– Hospitalization for several days if needed for monitoring
Supportive Veterinary Care
Even without antivenin, vets use supportive therapies to give the dog’s body time and support to metabolize and clear the toxins. This may involve:
– Oxygen therapy and ventilation if breathing is compromised
– Medications to control vomiting and prevent seizures
– Lowering body temperature if fever spikes
– EKG and blood pressure monitoring
– Intravenous nutrition if dog is unwilling to eat
– Wound cleaning and bandaging if bite site oozes or bleeds
With comprehensive veterinary treatment, dogs can make a full recovery within several days up to a couple weeks, depending on circumstances.
Home Care and Monitoring After Spider Bite
Once the dog is stable enough to return home, follow your vet’s instructions for care and watch for any recurrence of symptoms. Guidelines may include:
– Giving all prescribed medications as directed
– Checking the bite site daily for swelling, discharge, oozing
– Applying antibiotic ointment if needed to prevent infection
– Keeping the wound site clean and properly bandaged
– Returning promptly for wound checks and bandage changes
– Restricting activity to allow healing and prevent re-injury
– Monitoring appetite and hydration
– Watching for signs of persistent pain or discomfort
– Avoiding any known spider habitats during recovery
Call the vet right away if you notice changes at the bite site, return of symptoms like muscle tremors or lethargy, or any other concerns about the dog’s recovery. Generally, the prognosis is good for full healing within a couple weeks.
Preventing Spider Bites in Dogs
While not all spider bites can be avoided, some key prevention tips include:
– Have a professional exterminator treat your home and yard to reduce spiders
– Seal cracks, holes, and potential entry points spiders could use
– Remove piles of wood, debris, and clutter where spiders may nest
– Keep basements, sheds, and storage areas clean and dry
– Shake out or inspect items like boxes, plants, firewood before bringing indoors
– Use insect repellent products designed for spiders
– Supervise dogs closely when outside around woodpiles and dense vegetation
– Train dogs to avoid approaching spiders and critters
– Keep dogs on a leash in areas likely to have venomous spiders
Routine Veterinary Care
At annual check-ups, discuss spider bite prevention with your vet. They may recommend:
– Keeping dogs up to date on core vaccines and preventatives
– Giving anti-inflammatory medications before hiking or rural camping trips
– Carrying an emergency first aid kit and dog-safe insect repellent on outings
– Knowing your region’s most dangerous spiders and their habitats
– Asking about antivenin availability in case of a bite
Prompt veterinary intervention offers the best protection against lasting harm if a curious canine crosses paths with a venomous spider. With proper care, most dogs fully recover and avoid any permanent damage.
Conclusion
Dogs who ingest venomous spiders are at risk for moderate to severe envenomation depending on the type and amount of toxin delivered. Black widows, brown recluses, and other spiders common in North America and worldwide can produce neurotoxic and necrotic bites causing severe pain, muscle spasms, tissue damage, vomiting, breathing issues, paralysis, and death in some cases.
Immediate veterinary care is vital to treat symptoms, provide wound care, administer antivenin if indicated, and support the dog’s body through the effects of envenomation. Prompt treatment greatly improves the chances of a full recovery within a couple weeks for most bites. Prevention through professional pest control, training dogs to avoid spiders, and awareness of venomous species can help keep curious canines safe from the potential dangers of spider bites. With proper care, dogs bitten by venomous spiders can bounce back quickly and avoid any lasting health issues.