GP Guide to Large Local Reactions after Insect Stings
This guide is intended to provide advice to GPs regarding the management of
patients with a history of large local swelling reactions to insect venom. If a
patient has had a systemic reaction following insect sting a referral to the
Peninsula Specialist Immunology and Allergy Service is appropriate for
discussion about venom immunotherapy (available for bee and wasp). The
acute management of large local reactions will not be covered in detail
however a short course of regular antihistamines and or low dose steroids
may be appropriate depending on symptom severity and duration.
Large local reactions and the risk of progression to systemic reaction
The risk of a systemic reaction in patients with a history of large local
reactions in most studies is no more that 10%. Certain patients (eg, bee
keepers, pest controllers) may have a slightly higher risk than the general
population due to increased exposure. Most patients with a history of local
reactions will continue to experience similar reactions after subsequent stings.
It is somewhat of a myth that subsequent reactions get progressively worse
and instead the severity of a reaction on any one day is related to numerous
confounding factors such as temperature, stress, alcohol, inter-current illness
and medication as well as the amount of venom injected. Further allergy
testing at this stage is not necessary and the patient is not a candidate for
venom immunotherapy unless they develop a systemic reaction in the future.
It is obviously important that the patient has an emergency plan to deal with
any future stings; I would recommend the following steps:
1. Remove the stinger as soon as possible.
2. Move away from the hive/nest (if applicable).
3. Carry a mobile phone and know their location should medical attention
be required (rural locations often need GPS coordinates).
4. If the patient develops any severe symptoms such as throat
constriction, difficulty breathing, change in character of voice or
dizziness they should lay down on the floor, raise the legs, ring 999
and say the keyword ‘anaphylaxis’.
5. If symptoms are mild (itching, swelling at the site of sting) take 1-2
tablets of oral antihistamine and rest for at least 30minutes monitoring
for symptom progression.
There is no clear indication to prescribed self-injectable adrenaline in a patient
who has never had a systemic reaction; however it could considered on the
basis of high risk of exposure, patient anxiety or any coexisting asthma. If you
do decided to prescribe self-injectable adrenaline the patient requires two
devices to be carried at all times and education on their use.
Attached are two patient information leaflets about emergency plans with or
without adrenaline.