Insect bites and stings are common and usually only cause minor irritation. However, some stings can be painful and trigger a serious allergic reaction.
In the UK, insects that bite include midges, mosquitoes, fleas, bedbugs and, although not strictly insects, spiders, mites and ticks, which are arachnids. Insects that sting include bees, wasps and hornets.
An insect bites you by making a hole in your skin to feed. Most insects sting as a defence by injecting venom into your skin.
Symptoms of an insect bite or sting
When an insect bites, it releases saliva that can cause the skin around the bite to become red, swollen and itchy.
The venom from a sting often also causes a swollen, itchy, red mark (a weal) to form on the skin. This can be painful, but it's harmless in most cases. The affected area will usually remain painful and itchy for a few days.
The severity of bites and stings varies depending on the type of insect involved and the sensitivity of the person.
In rare cases, some people can have a serious allergic reaction (anaphylaxis) to a bite or sting that requires immediate medical treatment.
Read more about the symptoms of insect bites and stings.
When to seek medical help
See your GP if you've been bitten or stung and there's a lot of swelling and blistering or if there's pus, which indicates an infection.
Dial 999 and ask for an ambulance if you experience any of these symptoms after a bite or sting:
- wheezing or difficulty breathing
- nausea, vomiting or diarrhoea
- a fast heart rate
- dizziness or feeling faint
- difficulty swallowing (dysphagia)
- confusion, anxiety or agitation
Read more about the complications of an insect bite or sting.
Treating insect bites and stings
Most bites and stings are treated by:
- washing the affected area with soap and water
- placing a cold compress (a flannel or cloth soaked in cold water) over the area to reduce swelling
Try not to scratch the affected area to avoid infection. If you're in pain or the area is swollen, take painkillers such as paracetamol or ibuprofen.
If you have a more serious reaction, your GP may prescribe other medication or refer you to an allergy clinic for immunotherapy (desensitisation).
Read more about treating insect bites and stings.
Preventing insect bites and stings
You're more likely to be bitten or stung if you work outdoors or regularly take part in outdoor activities, such as camping or hiking.
Using insect repellent and keeping your skin covered when outdoors will help you avoid being bitten or stung.
Try not to panic if you encounter wasps, hornets or bees, and back away slowly. Don't wave your arms around or swat at them.
Read more about preventing insect bites and stings.
There's a risk of catching diseases such as malaria from insect bites in certain parts of the world, such as:
- South America
It's therefore important to be aware of any risks before travelling to these areas, and to get any necessary medication or vaccinations.
Last updated: 19 November 2015
Continue to next section: Symptoms of insect bites