Wasp sting allergy
Allergy to wasp venom.
About wasp sting allergy
A wasp sting injects venom that usually causes immediate pain, redness and swelling. Most people react only locally, but some develop a venom allergy in which the immune system produces IgE antibodies to wasp venom, so a later sting can trigger a rapid allergic reaction. Unlike bees, wasps can sting more than once and are often provoked around food, drink and bins, particularly in late summer. Anyone who has previously had a systemic reaction, and those stung frequently such as outdoor workers, is at greater risk of a serious reaction.
Reactions come on quickly, often within minutes. A normal sting causes pain, redness and swelling that settles over hours to a few days, and some people develop a larger local swelling around the site. A systemic allergic reaction is more serious and may cause widespread hives, itching, swelling of the face, lips or throat, wheeze, difficulty breathing, dizziness or collapse. This is anaphylaxis, a medical emergency that can be life-threatening.
A severe reaction needs immediate action: call 999, and use an adrenaline auto-injector without delay if one has been prescribed, repeating with a second dose if needed while waiting for help. People who have had a systemic reaction should be referred to an allergy specialist, who can confirm venom allergy with skin or blood tests and may recommend venom immunotherapy to reduce the risk of future severe reactions. Avoiding nests, staying calm near wasps and covering food and drink outdoors help prevent stings.
Common triggers
- Wasp sting and products containing it
Symptoms
- Pain, redness and swelling at the sting or bite
- Widespread hives or itching
- Swelling of the face, lips or throat
- Wheezing or difficulty breathing
- Anaphylaxis in severe cases
Avoidance & management
- Avoid nests, hives and known habitats
- Wear covering clothing and avoid strong scents outdoors
- Use insect repellent and screens
- Carry an adrenaline auto-injector if prescribed
- Seek urgent help for a severe reaction
Sources & references
Allergy safety: what everyone should know
Mild-to-moderate reaction signs
- Itching, hives or a raised rash
- Swelling of lips, face or eyes
- Tingling mouth, sneezing, runny nose
- Stomach pain, nausea or vomiting
Anaphylaxis — call 999 (UK) or 112 (EU) immediately
- Difficult or noisy breathing, wheeze, persistent cough
- Swelling of the tongue or tightness in the throat
- Dizziness, collapse, pale and floppy (young children)
- Use an adrenaline auto-injector (e.g. EpiPen) at once if prescribed, then call an ambulance even if symptoms improve
Allergy or intolerance? A true allergy involves the immune system and can escalate quickly; an intolerance (e.g. lactose intolerance) is unpleasant but not life-threatening. The symptoms overlap, so self-diagnosis is unreliable.
Getting tested: home-testing kits based on IgG are not diagnostically valid. If you suspect an allergy, ask a GP for referral to an allergy clinic for skin-prick or specific-IgE testing and a supervised food challenge where appropriate.