How to Recognise and Treat Insect Bites On Dogs

LAST UPDATED 3 APRIL 2024

As the sun graces us with its warmth and extended daylight, you're probably starting to picture outdoor adventures, hiking quests and beach trips with your beloved pooch! Yet who can forget the herald of Summer; the buzzing of mosquitoes, the hum of bees, and the tiny, often unseen, bites from various critters can turn a day of frolicking into a discomforting experience for our furry friends. Not just a pest to us, insect bites pose a common adversary for our furry friends too.

Understanding the signs, symptoms, and potential dangers of insect bites on dogs is crucial for responsible pet ownership. In this comprehensive guide, we delve into the world of these tiny adversaries, exploring how to identify different bites, recognizing allergic reactions, and offering practical insights on treating and preventing the discomfort that insect bites can bring to our canine companions. Let's embark on a journey to safeguard our dogs from the perils of insect encounters, ensuring they enjoy the outdoors to the fullest without the nuisance of unwelcome bites.

There are a vast number of insects that can bite our pets, resulting in a vast array of associated symptoms that you may see. However, the most common symptom is raised, red lumps or hives. The individual symptoms of different insects is discussed in more detail below.

Just like humans, some dogs can experience an allergic, or anaphylactic reaction to an insect bite, causing profound swelling, difficulty breathing, vomiting, diarrhoea, tremors, collapse and coma. These signs warrant immediate veterinary attention.

Mosquitoes

The mosquito bite is a familiar sight in Summer and the bites that appear on our pets look just like those on us! You'll probably notice a round welt under 1cm wide appear on your pup's skin. In pale skin dogs they may also appear red, but they are typically covered with fur. They will be itchy and typically occur individually, but sometimes can appear close together.

Bee and Wasp Stings

You've probably seen a picture of a dog post-bee sting. These are often depicted as 'cute' photos of dogs with their faces all swollen. This swollen face is typical of a severe allergic reaction though; not all dogs will swell up!

Some dogs may present with milder symptoms, including:
- Yelping, whining or limping due to pain
- Licking, chewing, scratching or pawing at the bite site
- Redness and swelling of bite site
- Hives
- Pain when touched
- Swelling
- Drooling
- Full body itch
- Visible sting/stinger

Fly and Midge Bites

There are a variety of biting flies in Australia, including Midges (Sand Flies), March Flies (Horse Flies) and Black Flies. All of these flies can inflict painful bites. Most will present as the typical raised, red swollen lump and occasionally with be very itchy.

Because these bites are often most painful when they initially occur, you will probably see your dog spin around or snap at these flies to shoo them away.

Ant Bites

Ants are commonly found in the backyard and it's easy for curious pups to sniff out a nest or accidentally lie down in an ant's nest. There are many types of feisty ants in Australia and some have a sting that is even more fearsome than its bite (don't forget the acid squirting Green Tree Ant!). It's uncommon for an ant bite to cause an allergic reaction, but always keep an eye on your pet.

Signs of an ant bite can include:
- Holding up the paw/leg
- Flicking or shaking the paw
- Sudden redness between the toes
- Licking or chewing at the bite site
- Mild swelling at bite site
- Small red spot, possibly with a white centre like a pimple (esp. Fire ants)

Spider Bites

If there is one thing Australia is well known for, it's our long list of deadly snakes and spiders. As such, pet owners generally know what to look out for in themselves, but what about your dog?

With a vast number of spiders in Australia, we can see a range of bite reactions as well, although they tend to be non-specific. Often a spider bite is never confirmed, or the species confirmed when it comes to our pets.

Most spider bites will induce a localised reaction, with a thick, red welt at the bite site often associated with tenderness or pain, and general lethargy. Sometimes tissue around the bite site may also die (skin may turn black and start to fall away or discharge).

Obviously, with some spiders, more severe reactions can occur, such as the Redback Spider. Redback venom affects the nerves, with initial pain at the bite site, followed by full body pain, particularly from touch. Other spiders can cause paralysis, muscle tremors, joint pain, anxiety/restlessness, limping/lifting the paw, difficulty walking, reduced appetite, vomiting, diarrhoea and difficulty breathing.

All spider bites should be taken seriously as there is no antivenom available and anaphylactic reactions can occur. Treatment is supportive and based on managing symptoms. If you suspect your dog has been bitten by a spider, take them to the vet immediately.

Flea Bites

Flea Bites might be the bites that owners are the most familiar with. These critters often leave small red, raised spots on the skin, typically around the base of the tail, back legs and belly. In severe infestations, the closely located bites may start to appear as a rash.

Other signs of fleas and flea bites can include:
- Flea dirt (flea faeces/digested blood) - if you dampen a piece of paper towel, flea dirt will stain red
- Scratching - may be accompanied by scratch wounds
- Hair loss
- Small scabs
- Thickened or discoloured skin
- Brown stained fur - from saliva staining
- Live fleas - a flea comb may help to find live fleas

Tick Bites

The Paralysis Tick is by far the most commonly known tick in Australia, but other ticks can affect our dogs, including the Bush Tick, Cattle Tick and Brown Dog Tick. While they won't cause a potentially fatal paralysis, these ticks can potentially transmit tick-borne diseases, such as Ehrlichiosis.

If your dog has been bitten by a tick, you will often find the attached tick or the remaining tick crater. An adult tick is an eight-legged, oval shape with two large mouthparts. When you find a tick, they will often already be engorged.

A tick crater is a round, raised, red swelling with a sunken crater in the centre. The crater may be bleeding when the tick initially detaches, but an older crater may have a scabbed centre and may not be as red.

Dogs can potentially have a severe allergic reaction or anaphylactic reaction to any insect bite. Allergic reactions are severe, can potentially be life threatening and require immediate veterinary attention. 

Seek immediate veterinary treatment if your dog shows any of these symptoms: 

• Swollen face, neck or limbs
• Welts or hives all over the body
• Lethargy
• Fever
• Whole body itching
• Anxiety or restlessness
• Inappetence
• Excessive drooling
• Vomiting
• Diarrhoea
• Pale gums
• Dizziness, disorientation or staggered gait
• Difficulty breathing or wheezing
• Seizures
• Paralysis
• Collapse
• Loss of Consciousness

Symptoms of an allergic reaction typically present within 20 minutes of a bite occurring, however, sometimes a delayed reaction may occur, not presenting for up to 4 hours. If you see any of the above symptoms at any point following an insect bite, seek immediate veterinary attention.

Sometimes the location of the bite can give us an indication of the likely insect that caused the bite. This is due to the lifestyle, habitat and nature of the insects, as well as the habits of our beloved furry friends. For example, if your dog has been sniffing around in a rose bush, they are probably going to get stung by a bee on their face!

There are a number of ways that you can prevent insect bites on your pet. From mosquitoes to spiders, try implementing some of the below aids to reduce the number of biting insects in your house and garden.

The first step is keeping up to date with parasite prevention. Most of these will keep your dog protected from fleas, ticks, mites and lice. We recommend using reputable products, such as Nexgard, Bravecto or Simparica. For full details on the level of parasite prevention your dog needs and which products are the best, check out our Flea Tick and Worming Guide for Dogs.

These products do not have claims against biting or stinging insects, only common parasites like fleas, ticks, mites and lice. So how can you protect your pet from other biting insects? Many commercial pesticides available on the human market are toxic to our pets, particularly DEET and essential oils including Citronella. Products using Pyrethroids (e.g. Permethrin or pyrethrin) also need to be used according to the directions, particularly around cats. Never spray a dog-only product or use a dog-only product on cats as pyrethroids are highly toxic to cats.

Fortunately, there is a preventative registered for protecting your dog against mosquitoes, midges and biting flies: Advantix!

In order for insects, ants and spiders to thrive in your garden, they need to have habitat to live and breed in. So make the yard an unpleasant place for them to be and remove breeding locations.

Mosquitoes breed in stagnant water, particularly that which is shallow, so remove any still, stagnant water sources or areas where water may accumulate. Change pet water bowls daily to prevent mosquitoes breeding in them, or get a water fountain to keep water moving. If your dog has a pool, be sure to change this regularly and keep an eye out for any wrigglers (mosquito larvae).

Spiders like dark corners and areas. Remove old tyres, wood or rubbish piles and lying leaf litter where they may hide. Try to keep garden sheds organised and prevent items from accumulating in the corners. Also prevent access to these areas for your pets.

If you find Wasp Nests or Bee Hives around the house, call a professional to safely remove them and keep your beloved pup inside and away from the action.

You can also actively prevent your dog from being exposed to some of the common insects that bite. Keep your dog on a leash on walks to prevent them walking over ant nests or sniffing in flower beds that might have lots of bees in them. Teach them to come when called so that you can call them away if they try to chase or snap at any bees.

Make traps, such as fly traps or ant baits. While some of these options may be toxic to pets, some homemade traps are perfectly safe to use. Consider an Apple Cider Vinegar and Dish Soap fly trap that is out of reach for your dog. You can also call a pest control professional if you have large problems with ants.

Avoid walking in swampy areas or flower gardens where there are likely to be lots of biting insects. Dark, damp areas are also more likely to harbour insects. You will find mosquitoes more active at dusk and dawn, and bees/wasps more active in the middle of the day, so try to avoid being outside at these times. While walking in the cool of the day, try to avoid areas that mosquitoes are likely to flock.

Where possible, use fly screens around the house to prevent insects getting into the house. You may also be able to use fly mesh around outdoor dog pens.

You may also be able to use coats and boots to cover patches that are likely to be bitten and protect them.

It's time to get your green thumb on and fight nature with nature. Many plant species have developed ways to protect themselves from predators, particularly insects, and these natural defence mechanisms can act as great repellents around the house. While some repellent plants also pose a risk to our pets, there are others that are perfectly safe to use. You might even be able to spice up your cooking in the process!

Placing repellent plants in the gardens, around the house in planter boxes or hanging baskets, or even inside the house can be a great way to reduce the number of insects, including mosquitoes, flies, ants, fleas and even spiders!

Our top recommended pet friendly, insect repelling plants are Basil, Rosemary, Lemon Balm, Catnip and Marigolds. The Venus Fly Trap is another great option! While this plant is non-toxic, like any plant, it may cause some digestive upset if consumed.

Dragonflies are the natural enemy of the mosquito, sometimes called a 'Mosquito Hawk', but also love to snack on midges, flies and any other flying insect they can catch. Dragonflies can eat 100 or more mosquitoes per day. We are very familiar with the concept of frogs eating flies, but a balanced diet would include a range of insects and invertebrates, including crickets, moths, cockroaches, worms, mosquito larvae, snails, slugs and spiders. Small lizards have a similar diet to frogs but may supplement it with plant matter.

There are also a variety of insectivore bird species that might help to clean up the mosquitoes around the yard. This list includes Magpies, Kookaburras, Kingfishers, Swallows, Sparrows, Chats, Whistlers, Robins and Starlings. 

All these species generally like water, such as a pond or water feature (any non metal, water holding container will work). They prefer still water or slow running water with aquatic plants, no deeper than 30-50cm. Ideally, place it in a low-lying area that is in partial shade. It's also a good idea to add in some light coloured rocks for lizards and dragonflies to warm up on. Frogs also like wooden logs and branches. Native plants make great options to attract birds and frogs to the garden. Small solar lights will attract other insect food sources to the pond as well.

Low-lying water sources can act as an attractant for toads as well. Planting dense shrubbery around a frog pond can help deter toads, and keep an eye out for their eggs (black dots in a jelly-like string), which can be picked up and removed. You may also want to make sure that a pond or water source in your backyard will be safe for dogs and kids. You won't be attracting any wildlife if your dog is always splashing in the pond!

An alternative option to attract native frogs, without adding in a water pond or feature is to build a frog hotel. These can be made with PVC pipes and frog friendly plants.

Some plants you may be able to look at for attracting dragonflies and frogs are: Canna Lillies (Be careful! Many other Lily species are toxic to pets), Cat Tail, Lotus Plants, Pitcher Plant (these carnivorous plants catch insects!), Papyrus, Marsh Flower (Villarsia exaltata) and Wild Bergamot. Keep in mind that any plant can potentially cause digestive upset if consumed. For a complete list of toxic plants, check out the ASPCA Toxic Plant List.

We do recommend keeping in mind that planting flowers in your garden will also attract bees. Use some of the management techniques above to reduce exposure. Basil, Rosemary and Marigolds can also help to repel bees.

Most insect bites and stings can be managed at home, depending on the insect and the bite reaction. Most bites will recede within 24-48 hours, especially bites from flies, midges, ants, mosquitoes and fleas. Some bee and wasp sting reactions may also be mild and recede within this period. So what first aid steps can you take to help your pet?

If your pet is bitten by something, the first step is to determine the offender. Using the signs above and location of the bite, you may be able to gauge the likely suspect. It definitely helps if you saw it happen though. If you suspect a spider bite is the cause or identify a tick on your dog, then be sure to take your pet to the vet straight away. Otherwise, you can follow the below steps:

Check For A Stinger: If you suspect a bee sting, remove the stinger. The stinger is usually a soft, brown, 2-4mm venom sack attached to a stinger that will be embedded in the skin. It is often located in an area of localised swelling. Try to scrape the stinger off with something flat, like a fingernail or credit card.

DO NOT squeeze or pinch the stinger, such as trying to grab it with tweezers. These can squeeze more venom into the sting site. If you don't feel comfortable removing the stinger at home, take your dog in to the vet.

Apply A Cold Compress: Cold helps to reduce swelling and pain. Wrap a cool compress, such as frozen vegetables, into a thin towel and apply it to the bite site. You can apply this for 5-10 minutes intermittently within the first 1-2 hours.

Prevent Them Licking: Licking or scratching at the bites can increase the irritation, create abrasions in the area and increase the risk of infection. Use Elizabethan Collars or other covers and preventatives to prevent access if your dog continues to lick or scratch at the site.

Soothe The Skin: Oatmeal baths are great for soothing irritated skin, especially in dogs that have multiple bite sites. This is a great option for dogs that don't mind getting bathed. Another option is to make a paste from baking soda and water to apply directly to the bite site.

Monitor Your Dog: Continue to monitor your dog at home. While most reactions occur within 30 minutes, sometimes a delayed reaction can also occur, so it is important to monitor your pup for the next 24 hours. If they show any signs of anaphylaxis, head to the vet immediately. It's also important to monitor over the coming days for signs of a secondary infection. Because bites break the surface of the skin, this can allow bacteria on the skin's surface, in the mouth or under scratching nails to enter into the skin and cause an infection. Signs of infection can include redness, swelling, heat, discharge and pain.

With so many biting insects and potential reactions, you might be struggling to determine what warrants a vet visit and what can be managed at home. Here are the key indicators of when to seek veterinary care:

Bite wounds can potentially become infected. The most common signs that indicate infection are swelling, redness, heat, pain and discharge, particularly pus.

If you suspect that a bite is infected, it is important to take your pet to the vet. When infection is present, prescription medications like antibiotics and anti-inflammatories are typically required to resolve this. Your vet will be able to determine if an infection is present, the likely cause of the infection and prescribe the correct treatment.

Yes, there are many alternatives to the old "Cone-of-shame". There are alternative cone options, such as soft cones or cloud cones. Or you can try using products like pet boots, t-shirts and coats to prevent your dog from accessing a bite. If you feeling like getting creative, you can also make a cone out of your dog's collar and a pool noodle. Cut the pool noodle into small lengths and feed them over your dog's collar (you may have to loosen it a little bit).

It can be difficult to identify a tick when you see one on your dog as there can be a lot of variation in their appearance. Paralysis ticks are often light grey to bluish in colour and when engorged have an orange mouth and legs. They have eight legs total with the front and back legs appearing darker. They have long mouthpart and no eyes.

If you suspect your dog has a paralysis tick, or are unsure about the type of tick on your dog, it is best to take them in to the vet so the tick can be identified and treatment can be started if it is a paralysis tick.

The short answer is yes. There are two main insect transmitted disease we are concerned about in dogs:

Heartworm: Heartworm is a parasite of serious concern in Australia. It is commonly diagnosed, particularly in the tropics, when prevention has not been used or has lapsed. Heartworm is transmitted by mosquitoes when they bite. As it's impossible to completely prevent mosquito bites, it's essential to have your pet on a heartworm preventative.

Tick-borne Disease: A tick-borne disease is any disease transmitted in the saliva of ticks. In Australia there are three tick-borne diseases affecting dogs, Babesiosis, Anaplasmosis and Ehrlichiosis. Ehrlichiosis is one of particular concern as a relatively new disease in Australia that is spread by the Brown Dog Tick. It is spreading rapidly and can be quickly fatal. To read more, check out our article Everything You Need To Know About Ehrlichiosis. 

Most bee and wasp stings will reduce and your dog will be back to normal within 12-24 hours. If your dog is experiencing symptoms for longer than this, it is best to take them to the vet for examination. If your dog has presented with more severe symptoms or anaphylaxis that required veterinary treatment, recovery may take longer than 24 hours.

Many of the commonly used and readily available insect repellents that we use to protect ourselves are toxic to our pets. I've gone through each of the common ingredients to look for and avoid below.

DEET (Diethyltoluamide or N-Diethyl-meta-toluamide): Chances are that you are familiar with DEET already. This product is commonly used in human mosquito repellents like Off! and AeroGard. DEET is highly toxic to our pets and should be avoided at all costs. These products can not only cause irritation if sprayed directly onto your pet, but they can also cause respiratory irritation if they are inhaled or if they are licked off your skin.

Essential Oils: We've all heard about the mosquito repellent properties of Citronella, but did you know that it's toxic to your dog? Many essential oils are toxic to our pets. Not only are many of them toxic when ingested, but they can also cause irritation from contact or inhalation (so avoid those citronella candles!).

Pyrethroids: Permethrin and Pyrethrin are commonly used in dog safe products for repelling insects, however, I do recommend keeping in mind that these are highly toxic to cats. Never use dog or human based products containing pyrethroids on or around cats as toxicity can be fatal.

It is also worth noting that these products need to be used according to the labels for dogs as they can cause toxicity if applied incorrectly. Human products should not be used around dogs. Human formulations, or products used in insect sprays, can be at doses that are toxic to dogs, so avoid spraying them around your curious pup.

If you are struggling with a bug problem, and want to bust out the Mortein (or something similar), here are some tips for protecting your pets: 

• Follow the safety instructions on the product label.
• Check the schedule, e.g. 'Poison' or 'Caution'. Most products are caution but if the product doesn't have either of these terms is is 'unscheduled' and a low risk to humans when used as per label directions.
• Exclude pets from the treatment zone and do not allow access until the product is dry (we recommend 24 hours). 
• Allow ventilation into the treatment zone so the product dries. 
• Do not spray around water sources, ponds or tanks, sprays are highly toxic to aquatic life and can contaminate water.
• If you use insect baits, make sure they are covered and inaccessible by your dog. These baits often contain food particles that are attractive to dogs.
• If using powders, make sure they are dispersed evenly (no clumps!) and prevent your dog from accessing the treated area. 
• Do not apply personal sprays around your dog, instead apply them away from your dog or use a roll on (don't let your dog lick your skin though). 
• Pets can make your house attractive to pests, so maintain good hygiene and home maintenance. Clean up any food spills and pet waste quickly. 

Everyday your dog is potentially at risk from being bitten by a vast variety of insects and arachnids. To provide them with the greatest chance of protection, be sure to implement a variety of preventative measures around your home. Learning how to recognise and treat the most common bites will prepare you for a prompt response when a bite does occur, especially in the event of a spider bite, paralysis tick or anaphylactic reaction. If you are ever in doubt, feel free to chat with our Vet Squad, or take your pet in to their local Vet for examination and prompt treatment.