An allergy is the overreaction of our immune systems to pollen, animal dander, mold, and dust. The immune system attacks these invaders by releasing histamine, which triggers itchy eyes, runny nose and congestion, and to alleviate these symptoms, we consume allergy medication.
Antihistamines block histamine. Histamine is a symptom-triggering chemical released by your immune system during an allergic reaction. They are one of the most popularly used categories of allergy relief medication, be it in the form of pills, liquid, nasal spray, or eye drops. For example, over-the-counter antihistamine eye-drops soothe itchy or watery eyes, while nasal sprays are commonly used to ease a runny nose. Oral antihistamines are also used to soothe hives, swelling, and other signs of allergies. These drugs may cause drowsiness and fatigue, so take them with caution if you are planning to drive.
Diphenhydramine and Chlorpheniramine are antihistamines that tend to cause drowsiness. While others such as Cetirizine (Zyrtec Allergy), Desloratadine (Clarinex) and Fexofenadine (Allegra Allergy) are less likely to affect your level of alertness.
Antihistamines are available as pills, liquids, inhalers, nasal sprays, eye drops, skin creams and shots (injections), over-the-counter or by prescription only.
Let’s take a look at the different options available:
Decongestants give quick, temporary relief from nasal and sinus congestion, but they can cause insomnia, headache, increased blood pressure and irritability. This type of allergy relief medication is not recommended for pregnant women or people with high blood pressure, cardiovascular disease, glaucoma or hyperthyroidism.
Antihistamine nasal sprays help ease sneezing, itchy or a runny nose, sinus congestion, and postnasal drip. These sprays may cause drowsiness or fatigue. Prescription antihistamine nasal sprays include Azelastine (Astelin, Astepro) and Olopatadine (Patanase).
Antihistamine eye drops are available over-the-counter or by prescription. These drops may combine antihistamines and other medicines to soothe itchy, red or swollen eyes. However, they might cause a headache and dry eyes. If you find that these antihistamine drops sting or burn your eyes, store them in the refrigerator or use artificial-teardrops before using the antihistamine ones.
Antihistamine tear drops include Azelastine (Optivar), Emedastine (Emadine), Ketotifen (Alaway), Olopatadine (Pataday, Patanol, Pazeo) and Pheniramine (Visine-A, Opcon-A, others).
Pills and liquids
Oral decongestants help to relieve congestion of nasal passage and sinus caused by hay fever (allergic rhinitis). Decongestants such as pseudoephedrine can be purchased over-the-counter.
Oral allergy relief medications may contain a decongestant as well as an antihistamine, namely, Cetirizine and pseudoephedrine (Zyrtec-D), Desloratadine and pseudoephedrine (Clarinex-D), Fexofenadine and pseudoephedrine (Allegra-D) and Loratadine and pseudoephedrine (Claritin-D).