Symptoms

After a bee or wasp sting, you will notice a small, itchy and painful bump, which rapidly disappears. This small local reaction is normal and is caused by toxic substances in the insect’s venom. This is not an allergy.

People predisposed to allergy can become sensitized to insect venoms and manifest allergic reactions when stung. Most of this group will only develop local allergic reactions. These are usually more severe than the non-allergic ones: painful swellings which often extend beyond the sting site, sometimes involving the whole limb if the sting was in the arm or the leg. These symptoms may last for a few days and sometimes require medical treatment.

In a few people (about half a per cent of the population) with allergy to insects, the sting will provoke a generalised reaction with a variety of consequences including some of the following:

• Generalized itching 
• Urticaria anywhere on the body 
• Generalised cutaneous flushing 
• Difficulty in swallowing 
• Abdominal cramps and nausea 
• Increased heart rate 
• Difficulty in breathing - due to severe asthma or throat swelling 
• A sudden feeling of weakness (a drop in blood pressure)
  and panic 
• Unconsciousness

During an anaphylactic reaction to insect stings, vital body functions such as respiration and blood flow, are at an inadvertant danger. Therefore, these reactions can be life-threatening.

Anybody who has experienced an unusually strong sting reaction, or experienced generalised reactions must see an allergy specialist. The doctor will tell you if your reaction was allergic or not. This is vital because, if you are allergic, you may react in the same way to a future sting.

Because the severity of a future reaction to a sting cannot be predicted, it is wise to be prepared with an emergency plan in case a bad reaction occurs. The doctor can teach you what to do in this situation and he can also prescribe for you the drugs which you should use to stop the development of a severe attack. Remember that these drugs must be with you all the time! You never know when or where you will be stung again!

If you have a severe allergy to insect stings, your doctor may consider that it may be appropriate for you to have a long-term desensitisation treatment (immunotherapy).

Even though immunotherapy is a very effective treatment, it is not without risk, the most serious of which is the possibility of anaphylaxis. Therefore, the decision to start this treatment must be considered very carefully with your allergy specialist.