Antihistamine Injections

While most people can find relief for typical allergy symptoms with over the counter antihistamine medications, there are some cases that require more extreme treatment. In case of a severe allergic reaction, an antihistamine injection is the most effective treatment available. People with life-threatening allergies, most commonly to food or insects, need the immediate relief that can be found in an injectable antihistamine.

Benefits of an Antihistamine Injection

With an antihistamine injection, the medication reaches the patient's bloodstream immediately, allowing the medication to take effect immediately. An antihistamine blocks histamine, which is the chemical in the body that is released during an allergic reaction. The medicine stops the action that the histamine takes on the tissue. In the case of a severe allergic reaction, the patient's throat can swell to the point that breathing is dangerously difficult, if not impossible. Antihistamines cannot prevent the allergic reaction, but they can stop the effect of the histamine on the tissue.

Antihistamine Injection Process and Side Effects

These injections are available by prescription only, and are generally used in emergency situations. The medication is injected directly into a large muscle. The side effects of the injectable antihistamine are much the same as the oral antihistamine, but exacerbated. Sleepiness, dry mouth or reduced appetites are common complaints after taking an antihistamine. Patients with medical conditions such as glaucoma, high blood pressure, heart disease, prostate problems or thyroid issues should be cautious before taking any form of antihistamine, as it can cause already narrow passageways to become even smaller.