Allergies are annoying, even if the most serious symptom your allergies cause is a runny nose. Fortunately, you don't have to learn to live with your allergy symptoms since many treatments are available, including antihistamines.

How do antihistamines work?

When you're exposed to something you're allergic to, like pet dander or pollen, your body produces a chemical called histamine. The role of histamine is to protect your body from the allergens, but unfortunately, it also causes the symptoms of allergic reactions. Runny noses, sneezing, coughing, and other allergy symptoms are caused by histamine's effect on your body.

Antihistamines work by blocking the production of histamine. If histamine isn't produced, you won't suffer any of the symptoms that usually accompany exposure to an allergen.

Are there different types of antihistamines?

There are two types of antihistamines: first generation and second generation. First generation antihistamines include drugs like brompheniramine, chlorpheniramine, and diphenhydramine, and they have a sedating effect on your immune system. Since these medications can make you sleepy, you shouldn't take them if you need to drive or do anything that requires alertness.

Second generation antihistamines include drugs like loratadine, desloratadine, and fexofenadine, and they aren't sedatives. These drugs won't make you sleepy and won't get in the way of your daily activities, so they're often used for long-term treatment of allergies.

Do antihistamines cure allergies?

Antihistamines aren't a cure for allergies; they're just a way to manage the symptoms. They control the production of histamine for as long as you take the medication, but as soon as you stop taking it, your body will produce more histamine.

Can long-term antihistamine use hurt you?

Short-term side effects of antihistamines include things like drowsiness, dizziness, and constipation, but the long-term effects can be much more serious. A University of Washington study found that people who took some types of antihistamines for three years or more had a 54 percent higher risk of developing dementia than people who took them for three months or less. Antihistamines can also lead to glaucoma, a sight-threatening eye disease characterized by high pressure inside the eye.

Are there any alternatives to antihistamines?

If you don't want to take antihistamines, ask your allergist about immunotherapy. This treatment involves injecting you with allergens over a prolonged period of time until you build up an immunity to the allergens. It can take 3 to 5 years to complete this treatment, but when you're done, your allergy symptoms will either be improved or completely gone.

Antihistamines are a popular treatment for allergies. They're not without risks, so before you try to treat an allergy with them, talk with a doctor at a clinic like Asthma and Allergy Clinic to learn about your treatment options.