You or someone you care for may well have been stung and have had some form of reaction and the question you want to know is: is this an allergic response or just an ordinary response?
One big caveat: I am not a scientist or doctor but supply information based on my judgement from having read the literature and talked to numerous victims and a few doctors and professionals!
If the response was just a local reaction with local swelling then without more complicated blood tests it is difficult to be certain. With something like hay fever it is quite clear that this is an allergic reaction. This is because there is no venom around to confuse the victim and mask the allergic symptoms.The histopathology of the cells around a bite are dominated by the venom initially and it is the venom which plays a prominent role in the swelling which is not always allergically mediated. It is always very possible that there is a small local allergic response to a sting and so the use of an antihistamine cream (or combination) should always be regarded as a sensible precaution.
If the response was a reaction with side effects elsewhere – let us say that you got stung on a finger and then you started to swell up your arm – then the probability is that the reaction is systemic and definitely an allergic reaction. The other effectsmay be just swelling, but they could be a rash, difficulty breathing, tummy ache, or a headache. Either way, any effects felt elsewhere on the body are probably due to the invovement of IgE which is the key allergy indicator.
Tests for allergy to insect stings are normally either:
- a blood test which tests for venom specific IgE in the blood (the so called RAST test)
- a skin prick test, where small amounts of venom are introduced subcutaneously and the response measured
However it should be noted that neither of these tests are definitive about future responses – there have been well documented reports on the occurence of false negative and positive results. People have been tested positive and stung shortly after with no ill effects! They have also been tested posivite and had bad sting reactions later on.
Most allergists and immunologists would consider case history and the personal experience of the patient to be a critical part of the diagnosis.
If you are unsure about your own situation then you are recommended to contact your doctor in order to arrange for tests.
As a general rule most people will have a local allergic reaction to a wasp or bee sting and so as a general rule the local application of an anti-histamine lotion (together with an anti-histamine medicine or tablet) can do no harm and may well do some good.