Most people will use an antihistamine at some point in their lives to treat a variety of symptoms, especially individuals who suffer from allergies. However, many people who take an antihistamine have little to no idea of how it works. Understanding the function of an antihistamine can help allergy sufferers to understand their conditions, which in turn can lead to better decisions about medications and health.
How do Antihistamines Work?
As its name suggests, an antihistamine works by opposing the actions of histamines. Histamines are released by the body in reaction to irritants. Their function is to cause tissues to inflame and to try to fight potential infections or diseases. When histamines are released, an individual may suddenly find himself suffering from any of a number of symptoms, including headaches, congestion, runny nose, scratchy throat, and irritation in the sinuses and on the skin. The patient may start itching, as the body responds to irritants. Some patients may sneeze excessively or have cold-like symptoms.
Histamines are an important part of the body's immune system. They can help to fight infection, which is why a similar set of symptoms often accompanies a fever or a cold. However, an antihistamine is necessary when the body overreacts to certain specific irritants. For allergy sufferers, these irritants are known as allergens, and they're often seasonal. Almost anything can be an allergen, and different allergens will often affect different allergy sufferers in very different ways. One or several of the symptoms listed above may accompany an allergy, which is why a proper diagnosis is important before an individual begins to take an antihistamine.
Antihistamine Receptor Blocking
When an antihistamine is taken, it blocks the receptors that accept the signals from the histamines that the body releases. By coating the receptors, the antihistamine stops the body from reacting normally (or more accurately, abnormally) to the effects of each histamine reaction.
Each antihistamine only works for a very short period of time, and as allergies affect people differently, one antihistamine may work well for one patient but fail to provide effective treatment for another. A histamine reaction may only be partially blocked, for instance, or it may be processed by the patient's body very quickly, which would result in a perpetual need of successive doses. Different amounts of an antihistamine may also be necessary.
How Long do Antihistamines Last?
An antihistamine should be at its maximum efficacy about two hours after it's taken. It will quickly wear off, leaving the body's receptors open and allowing allergic reactions to take place. Because of this, an effective antihistamine regimen usually involves re-dosing every three hours or so, depending on the antihistamine.
A good antihistamine can be a very effective means of treating an allergy. However, allergy sufferers will often need to try more than one antihistamine for the most effective treatment possible. Every patient should discuss antihistamine treatment with his or her doctor. This will provide the best course of treatment possible, allowing any allergy sufferer to live a normal life.