Bee and Wasp Sting Toxicity in Pets

Renee DiPietro, CVT
Veterinary Information Specialist 

Bees and wasps are two of the species in the insect order, Hymenoptera. These insects are important pollinators that help ensure the world food supply and the continuance of biodiversity. It is in our best interest to preserve them and treat them with respect.

Pets, especially dogs as they tend to be curious and nosy, can have harmful interactions with these insects.  With a little thought we can take steps to protect our pets, and these essential insects.

Rarely are these types of insects aggressive when unprovoked, so an insect’s sting is generally a defensive reaction to protect itself or its home.

Venom from these insects can cause reactions that can be localized, anaphylactic, and/or in the case of massive envenomation, toxic.

A sting is the injection of venom through the skin via the insect’s stinger. A bee can sting only once and dies after the sting. Wasps can sting several times in one episode.

Even dead bees or wasps can cause stings to pets when ingested. For example, if a dog eats a wasp nest that was recently sprayed with an insecticide to kill the insects, the act of swallowing recently killed wasps can cause stings to the pet’s mouth or throat. Ingestion of the pesticide may also be a toxicity risk.

Although stings to dogs are the most common, any pet can sustain a bee or wasp sting.

Whenever possible, the best protection is prevention.

The best way to prevent stings is to not allow your pet to harass a bee/wasp or its hive/home. If you are aware of a hive or other home of a stinging insect, options include having the nest removed/relocated by a professional or to restrict your pet from that area to reduce your pet’s risk of exposure.  Not all stinging insects live in visible hives. Some, such as bumble bees, ground hornets, and yellow jackets, may live in holes in the ground.

If your pet is persistently sniffing or digging vigorously at the ground it may be worth a quick investigation to ensure that they are not invading the home of a stinging insect. Make this investigation calmly and quickly to try and avoid aggravating insects and increasing your own risk for stings.

If you are allergic to stinging insects, try calling your pet back from a distance, or have someone who does not have a known bee/wasp allergy, investigate the situation. If evidence of presence or habitation is confirmed or suspected, retreat to a safe location and inspect your pet for stings. If one or two stings are found this may not be a reason for significant concern, but multiple stings can increase your pet’s risk of developing more serious symptoms.

Stings are often not witnessed.  Pawing at the face, swelling, redness, limping, chewing on a paw, or a short burst of vocalizing such as yelping or whining may all be indicators that an insect sting has occurred. If any of these signs appear it is a good idea to inspect your pet for evidence of an insect sting.

In most cases the clinical signs will be mild to moderate and can include: localized pain, swelling, redness and itching.

The location of the sting(s) is an important consideration due to the potential for swelling at the sting site; for example, stings to mouth, face, head, or neck can cause difficulty, and sometimes inability, to breathe. As dogs tend to investigate using their noses, the face is a common sting site in dogs.

Some pets, just like people, can develop severe systemic (anaphylactic) reactions to insect stings. In animals allergic to Hymenoptera venom, just one sting can cause anaphylaxis (severe life- threatening allergic reaction).

Likewise, massive envenomation (multiple stings) can cause toxicity in non-allergic animals.

It is important to monitor your pet closely for clinical signs for several hours after a sting.

If you can identify the insect that has stung your pet (take care to not be stung yourself) this can provide good information. Even a picture can be helpful to your veterinarian if veterinary care is needed. In some cases what is thought to be a bee or wasp sting may be a venomous spider bite. If you see the insect at all try to take note of what it is or take a picture from a safe distance.

For a single or few stings, in a pet that is not showing signs of a severe reaction, treatment is not generally needed.  A few measures can be taken to improve your pets comfort level more quickly.

If a stinger is still obviously present the first step is to try and remove it. This can be done with a gentle scraping motion with a thin but blunt object such as thin cardboard, a credit card, or a plastic butter knife. Avoid gripping the stinger in any way as this could promote injection of more venom into the sting site or possibly into your own fingers or hand.

You can also wash the area very gently with mild soap and water and then very gently pat dry.

Application of ice to the area can also help to reduce swelling and ease the discomfort. Ice can be applied every 4-6 hours for approximately 10 minutes at a time. Always insure there is a thin barrier between the ice pack and the skin. A doubled- up paper towel or a thin dish towel works for this and will help avoid injuring the skin by application of cold therapy.

Offer a quiet distraction. Now is not the time for active play but offering a favorite snack or chew toy (unless there are painful bites to the face), a brushing session, or a quiet leash walk may help your pet to quickly get over their insult and forget the discomfort.

Try to keep your pet from biting or scratching at the sting site(s) as this could cause further injury or infection. If your pet is persistently bothering an area of mild local reaction an Elizabethan collar can be used temporarily to protect the sting site from further aggravation.

If minor localized symptoms persist beyond a week or become worse than what developed in the initial 24 hours, it is best to check in with your veterinarian to see what their recommendations are or if they feel  the sting (s) should be evaluated.

It is best to not apply or administer any over the counter medications to your pet without consulting with your veterinarian first.  Over the counter medications and home remedies can at times do more harm than good.

The danger with insect stings is that some pets, just like people, can develop severe systemic (anaphylactic) reactions which are life threatening.

Signs to watch for after even just one sting include: severe skin redness, swelling, hives, difficulty breathing, general weakness, and persistent vomiting.

Stings to the face can also cause significant swelling which may impede breathing, eating, and drinking or swallowing.

Massive envenomation (multiple stings)animals can cause toxicity with the development of life-threatening clinical signs in non-allergic animals. 20 stings/kg has been demonstrated to be lethal for mammals.

Symptoms to monitor for after massive envenomation include depression, bleeding (blood in urine, feces, vomit), difficulty walking, dilated pupils, seizures, fever, and facial paralysis. In cases of massive envenomation treatment should be sought immediately regardless of whether symptoms have developed.

The first thing a veterinarian will do is assess your pet to determine the severity of the clinical signs and what type or reaction your pet is having. This will help them to develop a treatment plan that is appropriate for the situation and your individual pet.

Depending on the type of reaction your dog is having (localized, severe swelling, anaphylactic, toxic), and the severity of the clinical signs, the veterinarian will prescribe and administer treatments and supportive therapies that could include:

  • Antihistamines
  • Steroids
  • Epinephrine
  • Intubation
  • Oxygen Therapy
  • Fluid support
  • Pain control
  • Any other medical intervention as needed

 

For more information regarding Bee and wasp stings contact your veterinarian as they know your pet’s health status best and can give the best information regarding any health threat that may be encountered in your specific geographic area.

Let’s keep our pets and the bee’s safe!