Azelastine is an antihistamine used to treat seasonal allergies and allergies to environmental factors, such as pollution. In the United States, it is only available as a prescription nasal spray or eye drops. The medication is safe for most people to use under the guidance of a doctor.
Like other antihistamines, azelastine works by stopping histamine from reacting with the body. Histamine is a hormone that causes itchiness, swelling and irritation, and under normal circumstances, these immune responses keep a person healthy by helping to prevent attack by foreign bodies, such as viruses. Histamine reactions, when triggered by benign foreign bodies, such as grains of pollen or certain foods, are known as allergies. Antihistamines are commonly used to stop this unwanted histamine reaction.
Antihistamines stop the histamine from interacting with the body at times when the hormone creates more problems than it solves. Azelastine, like other antihistamines, treats symptoms such as runny nose, sneezing, and itching of the nose, eyes and face. Though the effects of this drug are the same as other antihistamines, it is chemically distinct from these them. A person who has had an adverse reaction to another type of antihistamine should not assume that azelastine will affect them in the same way.
Treatment with this medication is used to treat seasonal allergies as well as reactions to chemical irritants or pollution and is administered as either a nasal spray or as eye drops. As a nasal spray, the drug is inhaled directly into the nose, where it can quickly relieve the symptoms of seasonal allergies at the source of the problem. When in the form of eye drops, the medication is dropped into the affected eye, again, treating the histamine reaction in the area where it is causing discomfort. Relief from symptoms is usually seen within one hour of taking this medication, and its effects are most pronounced between 4 and 12 hours after taking it.
There are a number of side effects associated with the use of azelastine. Like many antihistamines, the most common side effect is drowsiness, which may be more pronounced if a person is taking another medication that also causes this symptom. Additional side effects are a bitter taste, headache, nausea, sore throat and weight gain. Women who are pregnant or nursing should consult with a doctor before taking this medication, as it is unknown how it could affect an unborn child or a nursing baby.