Which insects bite or sting?

Most insects in Australia are not harmful to people. Some of the insects that bite or sting are:

• ants
• bees and wasps
• mosquitoes
• bed bugs

Some caterpillars can cause painful, itchy and inflamed skin if their hairs stick into you.

Other biting or stinging animals

In Australia, there are other small animals that are not insects that bite or sting humans, such as:

• centipedes and millipedes
• leeches
• scorpions
• spiders
• ticks
• sea creatures
• snakes

The scorpions, centipedes and millipedes found in Australia are not venomous (don't give a poisonous bite or sting).

What are the symptoms of an insect bite or sting?

Insect bites and stings may cause:

• pain or a burning feeling
• swelling
• redness
• itch
• blisters

When should I see my doctor?

Most insect bites and stings will get better after a few days, and you won't need to see your doctor.

But if your bite or sting looks infected or does not get better after a few days, see your doctor.

When to seek urgent care

Get urgent medical attention if you've had an insect bite or sting and:

• the sting is in your mouth, throat or near your eyes
• you have more than one sting
• you feel dizzy or lightheaded
• you have abdominal (tummy) pain and are vomiting (being sick)
• a large area around the bite or sting has become red and swollen
• you have a high temperature and swollen glands
• your symptoms are getting worse
• you've had anaphylaxis to an insect bite or sting in the past

How is an insect bite or sting treated?

If a bee stings you, you may be able to see the stinger in your skin. Carefully scrape the sting out using the edge of your fingernail or something like a credit card.

Wasps and bull ants will rarely leave their sting in your skin.

If you get bitten or stung by an insect, ease your symptoms by:

• washing the area with soap and water
• applying a cold pack (wrapped in a cotton cloth)
• taking pain relief medicine

If you have ongoing swelling or itching, take antihistamines for up to 3 days. You can buy antihistamines at a pharmacy without a prescription.

If caterpillar hairs get stuck on your skin, remove them with tweezers or sticky tape.

See your doctor if your bite or sting does not get better after a few days or it looks infected.

Bites and stings from other animals — scorpions, centipedes, millipedes and leeches

Scorpion and centipede bites — clean your skin with soap and water. Use ice and pain-relief medicines to manage your symptoms. You may find that hot water helps with your pain, but be careful not to scald your skin. If your sting or bite is itchy, consider taking an antihistamine.

Millipede bites — a bite from a millipede can make your skin blister and discolour. Clean your skin with soap and water. Skin discolouration will get better with time and may take weeks to months to go away.

Leech bites — if you have a leech on your skin, apply salt, salt water or vinegar. This will cause the leech to fall off. Do not pull the leech off or use heat on the leech. Leeches will usually fall off after about 20 minutes without any treatment. Then wash the area with soap and water. Use a cold pack and take pain relief medicine to ease your pain and swelling. Apply pressure if your bite is still bleeding.

Other treatment options

Venom immunotherapy (desensitisation) is an effective treatment for bee and wasp sting allergies.

Treatment usually takes 3 to 5 years. Rebates may be available for this treatment through the Pharmaceutical Benefits Scheme (PBS).

Medicines for insect bites and stings

Some medicines can help ease your symptoms of a bite or sting, such as:

• antihistamines
• pain relief medicines, such as paracetamol
• steroid creams

Speak with your pharmacist for advice on these and other treatments.

What are the complications of insect bites and stings?

Insect bites and stings can lead to a variety of complications, ranging from severe allergic reactions, infections and toxic reactions.

Allergic reactions

Allergies to insect stings are one of the most common causes of anaphylaxis (severe allergic reactions) in Australia.

Severe allergic reactions are usually caused by stings from:

• bees
• wasps
• Australian Jack Jumper ant

Anaphylaxis to insect bites is less common. Anaphylaxis is treated with an adrenaline autoinjector.

The 2 brands of adrenaline autoinjector available in Australia are EpiPen and Anapen.

Your doctor will prescribe an adrenaline autoinjector if you have a severe allergic reaction to an insect bite or sting.

Infections

Insect stings and bites can sometimes become infected. An infection can happen days after the insect bite or sting. If this happens, your skin will become warm, red and painful to touch. You will need antibiotics from your doctor to get better.

Repeat exposure to ant stings may increase your sensitivity to their venom. The more you get stung, the more likely you are to have an allergic reaction.

If you are stung multiple times by a large group of bees or wasps, get medical attention. You may have a toxic reaction (envenomation) after 500 or more bee or wasp stings. Envenomation can cause death.

Can insect bites and stings be prevented?

There are things you can do to lower your chance of getting an insect bite or sting.

Try to cover up as much as possible when outside. If gardening, wear:

• long sleeves
• long pants
• gloves

Always wear closed shoes outside if you're allergic to insect bites or stings.

Wasps like sweet food and drinks. You can lower your chance of being stung by:

• not drinking from open cans of sweet drinks when outdoors
• making sure all food and drink are covered
• cleaning up sticky spills quickly

Other things you can do are:

• not wearing perfumes
• avoid being outdoors at dawn or dusk
• use an insect repellent containing DEET

It's important to leave insect nests alone. Always have ant, bee and wasp nests removed by professionals.

You can help prevent bites and stings by teaching your child not to disturb insects and where insects live.

Resources and support

• St John Ambulance Australia has a guide for bites and stings.
• The Australian Bites & Stings app contains first aid instructions on what to do if bitten or stung by an insect. It's free to download.
• Learn how to protect yourself from mosquito-borne disease with information from the Victorian Government in English and other languages.
• Visit the Australasian Society of Clinical Immunology and Allergy's (ASCIA) website for information on first aid for anaphylaxis in English and other languages.
• Call the Poisons Information Centre on 13 11 26 for advice on bites and stings.
• For effective ways to treat head lice at home, read healthdirect's article on head lice.
• For flea bite treatment and control, read the Victoria Department of Health's article on Fleas - Pest Control.

You can also call the healthdirect helpline on 1800 022 222 (known as NURSE-ON-CALL in Victoria). A registered nurse is available to speak with 24 hours a day, 7 days a week.