Insect Bites and Stings
Most bites and stings cause pain, itch and swelling that settle within a few days. A few people have severe allergic reactions (anaphylaxis), which need adrenaline straight away. Knowing the difference is the whole game.
What’s normal. A sore, red or itchy lump that may swell. A large local reaction (swelling bigger than your palm, sometimes a whole limb) peaks over 1 to 2 days and settles within a week; it’s uncomfortable but not dangerous on its own. On brown and black skin, redness may look purple or darker, and bites can leave dark marks that take months to fade.
Anaphylaxis is a whole-body reaction, usually within minutes: difficult or noisy breathing, swelling of the tongue or throat, wheeze or persistent cough, hoarse voice, dizziness or collapse, or (in children) going pale and floppy. Hives or vomiting after a sting can be part of it. In Australia, bees, wasps, jack jumper ants and ticks cause most severe reactions. For jellyfish and sea creatures, see marine stings.
The bites and stings ladder
Most need only first aid. Anyone who has had a severe reaction should see an allergy specialist: venom treatment works.
- Step 1 · First aidGet the sting out fast, then cool itBees leave a barbed sting: flick or scrape it out straight away with a fingernail or card edge, without squeezing it. Wash, then apply a cold pack wrapped in cloth and raise the limb.
- Works
- Removing a bee sting quickly limits the venom; cold packs ease pain and swelling
- Cost
- Free
- How long
- Minutes to hours
- Watch for
- Any breathing trouble, throat swelling or collapse: emergency (see below).
Speed beats technique. Scrape it now, admire your method later.
- Step 2 · PharmacyAntihistamine tablets, pain relief, a mild steroid creamFor itch and swelling. A non-drowsy antihistamine by day; paracetamol or ibuprofen for pain.
- Works
- Ease itch and swelling for most local reactions; they don’t prevent or treat anaphylaxis
- Cost
- About $5–20
- How long
- A few days
- Watch for
- Don’t rely on an antihistamine for a severe reaction: adrenaline comes first.
Great for the itch. Useless for the throat.
- Step 3 · First aidTicks: freeze, don’t squeezeIn Australia, kill the tick with a freezing spray (from a pharmacy), let it drop off, or have it removed by a doctor. Don’t pull, squeeze or poke it with chemicals.
- Works
- Freezing is the approach recommended by Australian allergy experts to reduce reactions
- Cost
- About $15–30 for a freezing spray
- How long
- Minutes
- Watch for
- People with tick allergy should have the tick removed in an emergency department. Tick bites can rarely cause red meat allergy.
Tweezers in a panic squeeze more tick into you.
- Step 4 · GPInfected bites or big reactionsScratched bites can get infected (spreading redness, pus, fever). Very large swelling sometimes needs steroid tablets.
- Works
- Antibiotics treat infection; steroid tablets can ease very large reactions
- Cost
- GP visit; medicines under the $25 PBS co-payment
- How long
- Days
- Watch for
- A red, warm area that keeps spreading after the first 2 days is more likely infection than allergy.
Day 1 swelling is usually allergy. Day 3 spreading is usually bugs.
- Step 5 · EmergencyAdrenaline for anaphylaxisLay the person flat (or sitting if breathing is hard), give an adrenaline autoinjector into the outer thigh, and call 000. A second dose can be given after 5 minutes if no better.
- Works
- Adrenaline is the first and most important treatment for anaphylaxis
- Cost
- Autoinjectors are PBS-subsidised with a prescription
- How long
- Immediately
- Watch for
- Don’t stand or walk the person. Stay at hospital for observation afterwards.
If in doubt, give adrenaline. It’s safer than waiting.
- Step 6 · SpecialistAllergy testing and venom immunotherapyFor people who’ve had a severe or whole-body reaction to bee, wasp or jack jumper ant stings: regular injections build tolerance.
- Works
- Whole-body reactions to a later sting fell from about 4 in 10 to about 3 in 100 in trials
- Cost
- Bee and wasp venom: PBS-subsidised; specialist fees vary; jack jumper ant venom only at a few centres
- How long
- Usually 3–5 years
- Watch for
- Reactions to the injections themselves can happen, so it’s given under supervision.
The rare treatment that turns a life-threatening allergy into a mostly ordinary one.
Save your money
Popular, heavily marketed or often asked about, but the evidence is weak or says no.
- Vinegar, baking soda, toothpaste or onion on a stingNo good evidence for insect stings. A cold pack does more. (Vinegar is for some tropical jellyfish only.)
- Pulling, squeezing or smothering a tickSqueezing can inject more of the tick’s saliva. Australian allergy experts advise freezing it instead.
- Antihistamines instead of adrenaline in anaphylaxisThey don’t treat breathing problems or low blood pressure. Adrenaline first, always.
What you can do
- Use an insect repellent containing DEET outdoors, and cover up at dawn and dusk.
- Wear shoes outside and gloves when gardening; don’t disturb nests.
- Check skin for ticks after bush walks, especially in coastal eastern Australia.
- If you’ve had a severe reaction, carry your adrenaline autoinjector and an ASCIA action plan everywhere.
See your GP if
- A bite or sting is getting more red, hot, painful or spreading after 48 hours
- You had hives all over, vomiting or dizziness after a sting, even if it settled
- You have a big local reaction every time
- A rash, fever or flu-like illness follows a tick bite or travel
Anaphylaxis is an emergency. For difficult breathing, throat or tongue swelling, wheeze, dizziness or collapse after a bite or sting, use an adrenaline autoinjector if available and call 000 (Australia) or your local emergency number. From a mobile, 112 works in most countries.
Australian spiders. For a suspected funnel-web or any big black spider bite in eastern Australia, apply a firm pressure bandage over the bite and up the whole limb, keep the person still, and call 000. For a redback bite, don’t bandage: use a cold pack and get medical help if pain is severe or spreads. For snake bites, use a pressure bandage and call 000. Poisons Information Centre: 13 11 26.
Common questions
Should I scrape or pull out a bee sting?
Either, as long as it’s fast. Getting it out quickly matters more than how. Try not to squeeze the venom sac.
Is a huge swollen arm after a sting an allergy emergency?
Usually not, if it’s only swelling around the sting with no breathing or whole-body symptoms. People with only large local reactions have under a 1 in 10 chance of anaphylaxis with later stings. See your GP if it’s very uncomfortable.
Do I need an adrenaline autoinjector?
If you’ve had anaphylaxis, or are at risk, your doctor will usually prescribe one with an ASCIA action plan, and refer you to an allergy specialist.
How do I take off a tick?
In Australia, the advice is to freeze it with a pharmacy freezing spray and let it drop off, rather than pulling or squeezing it.
Helpful resources
- ASCIA: Allergic reactions to bites and stingsAustralia’s allergy experts on first aid, ticks, prevention and venom immunotherapy. Free.
- ASCIA Fast Facts: Insect and tick allergyShort printable summary, with signs of anaphylaxis. Free.
Evidence and more information
- ASCIA: Allergic reactions to bites and stings
- ASCIA: Insect and tick allergy
- Cochrane: Venom immunotherapy for insect sting allergy (2012)
- NSW Agency for Clinical Innovation: Snake or spider bite
maladywise.com/bites-and-stings/