Allergic reactions occur when the body's immune system, the collection of processes and parts responsible for fighting infections, detects a foreign substance in the body and launches an assault on the invader as if it were a bacteria or virus. For this reason, the typical allergy symptom will be akin to that which occurs when the body attempts to fight off a cold or flu, such as watery eyes, runny nose, and sneezing. Common substances that elicit this overreaction include pet dander, tree and grass pollen, cigarette smoke, insect stings, certain foods, and just about any other item that the human body can come into contact with. However, some allergic responses can go far beyond what normally occurs when the body is fighting a pathogenic invader. Many food allergies, with the peanut allergy being one of the most common, can cause a massive immune system response in certain individuals that can cause such severe swelling that the individual may not be able to breathe. These massive allergic reactions can even be fatal. Fortunately for allergy sufferers, there are a number of allergy relief medicine options that can be used to treat the disorder with varying degrees of success.

Most allergies are caused by the chemical histamine, which works to expel particles from the body via increased nasal and eye secretions as well as through sneezing and coughing. That is why the most common class of allergy medications are known as antihistamines, since they serve to block or inhibit the activity of histamine. Many sufferers of mild allergies can find relief over the counter since many antihistamine drugs are available without a prescription.

For those who can not find allergy relief through over the counter medication, a trip to the doctor is necessary. There are a number of things that a physician can do to help. A number of powerful prescription based medications based on antihistamines can help. Others may require the use of more powerful drugs such as steroids. Steroid allergy treatments are typically administered via an injection or through a nasal spray or mist. For those who do not find relief from any of the allergy medication that their physician described, the next step is usually to visit an allergy specialist. An allergist usually would put the patient through a number of tests to try to localize the substance that is causing the allergic reactions to occur. Once isolated, it may be possible to either treat the allergies more effectively by tailoring the medications that are used or by simply having the patient avoid all contact with the substance. Another option is to use gradual exposures to the allergen in order to gradually decrease the degree to which the patient is allergic to the substance.