Allergy shots are taken to stop or reduce allergy attacks, especially for those people who suffer from frequent allergy attacks. Allergy shots (injections) are taken at regular interval for few years (3 to 5 years). Allergy shots are only long term solution for allergy (other allergy treatment modalities such as use of antihistamines, steroids etc. provide only temporary relief) problems and it is a type immune therapy. Each allergy shot/injection contain minute quantity of allergen (that cause/trigger allergic reaction in you) and the quantity of allergen in each allergy shot is just enough to initiate an immune reaction but cannot cause full blown allergic reaction.
The dose of allergen is gradually increased over time in each subsequent shots at particular/fixed interval. This gradual increase in allergen in allergy shots helps to desensitize (get used to the allergen) your body against the allergen. This procedure takes time and over few years’ time your body become immune to the effect of allergen and symptoms of allergy diminish when exposed to natural allergen.
What are the possible side effects/reactions of allergy shots?
Majority of individuals taking allergy shots for treating allergy problem usually do not show any reaction or side effects. However, as the allergy shots contain the allergen, it may lead to certain side effects, such as
- Anaphylaxis: this is the most serious side effect that may occur while taking allergy shots. Anaphylaxis is hypersensitivity reaction and need minute quantity of a substance to produce it. Hence, the minute quantity of allergen present in allergy shot may lead to anaphylaxis, especially during the first allergy shot. Anaphylaxis is a life threatening medical emergency condition and may develop immediately after injection of allergy shot or may be up to 30 minutes late. This is the reason your doctor may ask you to remain at least for 30 minutes after giving you the allergy shot. And this is the reason allergy shot should always be taken in doctor’s office or hospital, where medicines are available to handle the emergency situation.
- Local reaction at injection site is another problem that may appear after allergy shot. Redness, swelling, irritation at injection site may occur. The reaction may take few hours to appear and disappear on its own thereafter. No specific treatment is generally required for local reactions.
- Systemic reaction (less common) can occur and are generally more serious. Symptoms of systemic reaction include, hives, sneezing, nasal congestion etc. Serious symptoms include chest discomfort, wheezing, swelling in throat etc. Systemic reaction to allergy shot require medical attention.
Be regular in taking your allergy shots to reduce risk of side effects. Taking antihistamines also help. Most side effects/reactions occur within 30 minutes of injection and generally your doctor ask you to wait for 30 minutes after allergy shot. If you develop reaction after leaving doctor’s office return to your doctor’s office or to nearby emergency medical setup.