Insect bites and stings
Most insect bites and stings cause redness, swelling and itching that settle on their own within a few days.
How long does a course usually last?
Antibiotics are only used if a bite becomes infected, usually a 5 to 7 day course.
Your prescriber sets the exact length for you. Finish the course you're given unless a healthcare professional tells you to stop.
Never re-use antibiotics
- Do not re-use this treatment, or take leftover or someone else's antibiotics, unless a healthcare professional has expressly told you to.
- The right antibiotic, dose and length depend on your current infection, which can be different from last time.
- Re-using antibiotics can be ineffective, cause side effects, and drives antibiotic resistance. Return leftovers to any pharmacy for safe disposal.
What the guidance says
NICE advises that most insect bites and stings do not need antibiotics. Redness and itching soon after a bite are usually an inflammatory or allergic reaction, not infection. Cool compresses, painkillers and antihistamines can help. Antibiotics are only offered if there are signs of infection, such as spreading redness, pus or fever.
Based on NICE guidance — always follow your own prescriber's advice.
Antibiotics sometimes prescribed
When to seek help
If you are getting worse, develop a high fever, feel confused or breathless, or your symptoms are not improving as expected, contact your doctor or call NHS 111. See the warning signs page.