An allergic reaction is the immune system's response to antigens, or foreign substances, such as harmful toxins from bug bites, which invade the body. People can also experience allergic reactions to otherwise harmless substances, such as pollen and pet dander. These are often referred to as allergens. An allergic reaction is actually a hypersensitive response that can be mildly uncomfortable, or even deadly, for the affected person.
When the body detects an antigen, as occurs with a spider bite, white blood cells, the body's infection fighters, produce antibodies that are specific to that antigen. The purpose of antibodies is to attack and destroy the antigen through the production of histamine. Although histamine destroys the antigen, it also affects local body tissues and is what causes people to experience what they term an allergic reaction.
If you're allergic to certain bug bites, you're body will produce the same response each time it encounters that specific antigen. A common reaction to bug bites is inflammation. You might notice the skin around the site is red and swollen. It might also feel itchy or tender to the touch. Although most allergic reactions are relatively harmless, others are more serious and can affect the entire body. For example, anaphylaxis is a life-threatening allergic reaction.
Ticks are one type of bug that can cause allergic reactions. The Western black-legged tick and deer tick are also carriers of Lyme disease bacteria. An early indicator that you might have been bitten by an infected tick is a bulls-eye rash at the site. A bite from a black widow spider can cause a fatal allergic reaction. Victims usually experience shooting pain, redness and tenderness, as well as a nodule at the site. The venom also causes a dramatic increase in blood pressure, so it's important to seek immediate medical attention. The brown recluse is another bug whose bite can cause a deadly allergic reaction. Although its venom is extremely toxic, you might not feel its bite. However, you will notice a red bulls-eye and blistering. Also, the site will be extremely painful. Other bugs that cause non-lethal but irritating symptoms are chiggers, bed bugs, scabies and cockroaches.
In most cases, the symptoms of an allergic reaction can be alleviated by taking an over-the-counter antihistamine for redness and itching. Likewise, you can take ibuprofen to reduce the pain and apply ice to help with swelling. If you experience an anaphylactic response, it's important to seek immediate medical attention. Most people who've had a severe allergic reaction carry an epinephrine injector, often referred to as an "Epi-Pen." Administer your Epi-Pen and apply a tourniquet directly above the site of the bug bite, then call for help.
Most people who repeatedly experience allergic reactions know what causes them and can take preventative measure to avoid those particular allergens. With respect to bug bites, simply being aware of your environment can help prevent a reaction. If you plan on hiking through the woods, wear long clothing that protects your arms and legs, and be sure to check your body periodically for signs of irritation. Likewise, keeping your home environment sanitary can discourage harmful pests, such as bed bugs and cockroaches, from taking up residence.