allergy shot side effects
In the same way that vaccines protect us from disease by introducing our bodies to small amounts of the very things that can make us sick, allergy shots can help the body develop resistances and tolerances to the substances that can trigger allergy symptoms. But, while allergy shots are designed to protect you from your allergies, there is a small risk that you can have an allergic reaction from your allergy shot. Reactions are rare and can range from mild symptoms such as itching and redness at the site, to a serious anaphylactic reaction. For this reason, allergy shots should be taken seriously and always be administered under medical supervision.

Subcutaneous allergen immunotherapy, or allergy shots, are the most widely used immunotherapy treatment in the United States. Patients follow a build-up phase of increasing doses and concentrations of individually prepared allergy extract for approximately three to six months. During this time, allergy shots are usually given once or twice a week. Once a patient reaches their maintenance dose, allergy shots can be taken less frequently – usually once a week or every other week.

Allergy shot side effects are usually mild

The side effects of allergy shots are usually mild, but as concentrations and doses increase, so can the risk of local or systemic reactions. Local reactions are usually mild in nature and can include redness, itching and/or swelling at the injection site. Systemic reactions can affect the entire body and involve symptoms such as a runny nose, sneezing or hives.

Anaphylaxis is a severe and potentially life threatening systemic allergic reaction marked by swelling in the throat, chest tightness, wheezing, nausea and dizziness. It can be similar to the serious reactions some people have to peanuts or bee stings. Anaphylaxis requires immediate medical treatment and could require the use of epinephrine, also known adrenaline, to reverse the reaction.

Precautions against potential side effects

Because exercise can increase blood flow to the body’s tissues, it can also cause allergy extract from the allergy shot to be absorbed into the body faster. For this reason, patients should avoid strenuous exercise for one hour before and two hours after receiving an allergy shot. Additionally, patients should talk to their physician about any other medications or supplements that they may be taking as these may interfere with allergy shot treatment. Women who are pregnant or planning to become pregnant should also consult their physician with respect to allergy shots. Allergy shots are covered by most insurance plans.

Dr. Jeffrey Hallett administers allergy shots on a walk-in basis during specified hours Monday through Thursday. While appointments are not required, patients are urged to check the Allergy Injection Calendar at to view the most up-to-date schedule. Just look for the button that says “Calendar.”

View the Injection Calendar

Medical Center: 8285 Fredericksburg Rd San Antonio, TX 78229 | Lincoln Heights: 999 E Basse Rd #118 San Antonio, TX 78209