When Reaching For An OTC Allergy Medicine, Here's What You Should Know

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Warmer weather means allergy misery for millions of people, but there are some ways to find relief.

M​ore than one in four adults in the U.S. has some level of seasonal allergies, according to the Centers for Disease Control and Prevention. Symptoms of allergic rhinitis, more commonly called hay fever, are most common in the spring, summer and early fall.

T​he first step to relief is limiting exposure to substances that cause hay fever, the Mayo Clinic says. For seasonal sufferers, that's usually pollen from trees, grasses or weeds.

(MORE: How Climate Change Is Making Allergy Season Worse)

Many people turn to over-the-counter or prescription allergy medicines. But the different types available, when to use them and how to use them can sometimes be confusing. And, sometimes, it takes the right mix of more than one medication or switching to something different to get the best results.

H​ere's a guide to some common types of allergy medicines, based on information from the Mayo Clinic, Cleveland Clinic and the CDC. Remember to consult a medical professional for advice on which options might work best for you, follow package instructions on use and beware of any side effects or individual pre-existing conditions.

A​ntihistamines Work Best Against Irritating Symptoms of Hay Fever

A​ntihistamines work by blocking a chemical released by the body's immune system during an allergic reaction. That chemical, called histamine, is what causes allergy symptoms like sneezing, itchy eyes and a runny nose.

Both prescription and o​ver-the-counter antihistamines are widely available. Oral antihistamines are most common and can often be used daily.

(MORE: The 10 Worst US Cities For Seasonal Allergies)

N​ewer, second-generation versions of antihistamines are considered safer than older versions. They are sold under several brands. Common generic names are cetirizine, fexofenadine and loratadine. Steroid-free antihistamine nasal sprays, such as Astepro, also are now available.

“They all do the same job of blocking the same receptor, but some patients say one medication seems to work better for them," Cleveland Clinic allergist Dr. Mike Aronica advises. "And in that case, that’s the medicine you should use.”

Antihistamine eyedrops can help with itchy, water eyes.

D​econgestants Help With Stuffy Noses

Oral antihistamines are not as effective against congestion as they are other symptoms. That's where decongestants come in. D​econgestants like pseudoephedrine are sold as tablets or liquids and target nasal stuffiness and pressure.

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Sometimes, they are paired or combined with other medications that treat different allergy symptoms. Brand names of antihistamines with a "d" added at the end, for example, also contain a decongestant. So if you're already taking one of those, don't add a separate decongestant on top of it.

O​ral decongestants shouldn't be used on a daily basis.

What About Steroid Nasal Sprays?

Steroid sprays that work by reducing inflammation in nasal passages also are available over the counter.

“Nasal sprays really are the best medical therapies we have for managing allergic rhinitis,” Dr. Aronica says. “I tell my patients to start using nose spray at least two to three weeks before allergy season starts.”

T​he American Academy of Allergy, Asthma and Immunology, says there are benefits and risks that come along with over-the-counter corticosteroids.

There are also decongestant nasal sprays. Doctors say they shouldn't be used for more than two to three days at a time. Doing so can cause rebound swelling, which can make symptoms worse rather than bring relief.

N​asal Saline Rinses And Sprays Also Bring Congestion Relief

N​asal saline sprays and rinses are simple mixtures of water and salt. They're sold over the counter and can be used whenever needed. Rinses can also be made at home.

Sprays help thin mucus and moisten nasal passages. Rinses help with stuffy noses.

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