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Hay fever sufferers may get better relief from a nasal antihistamine than from an oral antihistamine, a clinical trial shows.

Astelin is a twice-a-day nasal spray. Zyrtec is a once-a-day pill. Both significantly relieved the runny nose, sneezing, itchy nose, and nasal congestion of seasonal allergies in the 300-patient study.

But on average, Astelin tended to work a little better and a little faster for these patients with moderate to severe hay fever symptoms. More importantly, patients taking Astelin reported more improvement in their quality of life than those treated with Zyrtec.

Jonathan Corren, MD, medical director of Allergy Research Foundation Inc. in Los Angeles, is a researcher for the study.

"Astelin is a very good option for patients," Corren tells WebMD. "Most people, when they think of allergy treatment, only think of oral antihistamines. But if they haven't responded well to oral agents, there may be an improvement with this drug. This is a very variable disease. Not all patients respond to the same treatments."

The study findings appear in the May issue of Clinical Therapeutics.

Faster Action With Astelin?

Astelin maker MedPointe Pharmaceuticals sponsored the study. It called for patients to go off their allergy medicines for one week, giving their seasonal allergies a chance to make their lives miserable. Then the patients got both a pill and a nasal spray. For half the patients, this meant a fake pill and real Astelin. For the other half, it meant getting a saline nasal spray and real Zyrtec.

Saline nasal spray does, indeed, help relieve some allergy symptoms. That's probably why the group getting Zyrtec reported some relief right away, even though earlier studies showed that the drug takes effect in about two hours.

Even so, an hour after treatment the group that got Astelin reported more relief that those who got Zyrtec.

"When you put an antihistamine right into the nose you deliver the drug more quickly and efficiently and get quicker onset of action," Corren says. He notes that Astelin appears to have other antiallergy effects in addition to working as an antihistamine.

That's true, says Eli O. Meltzer, MD, co-director of the Allergy & Asthma Medical Group and Research Center in San Diego and clinical professor of pediatrics at the University of California in San Diego.

"If I had a gun to my head and had to say which of the two antihistamines is more likely to provide relief, I would say Astelin because it has some effects beyond histamine blocking," Meltzer tells WebMD.

Overall, Corren's study showed that the average patient got about 25 percent more relief from overall allergy symptoms with Astelin than with Zyrtec. But both he and Meltzer point out that no single person is an average patient. Both experts say that seasonal allergies affect different people in different ways -- and respond differently to allergy treatments.

"This is a very variable disease," Corren says. "The more arrows we have in our quiver, the better, because people vary widely in their response to treatment."

Patients With Runny Noses but Without Allergies

Corren, an allergist, says that about half of the patients who come to see him for runny noses and nasal congestion aren't really suffering from allergies. They are suffering from nonallergic rhinitis, he says. And those patients may do better on Astelin, which is the only antihistamine approved for nonallergic rhinitis.

But for people who truly have serious seasonal allergies, Corren and Meltzer agree that the best initial treatment is not an antihistamine at all. Steroid nasal sprays, they say, tend to be most effective.

"For people that have mild to moderate symptoms, particularly those without nasal congestion or who have intermittent symptoms, either an oral antihistamine or a topical antihistamine like Astelin would be proper," Corren says. "But when you move into a patient population like in this study, with moderate to severe symptoms -- particularly when congestion is present -- a nasal steroid is preferable."

"If you ask the question, 'What is the first-line treatment for people with persistent seasonal disease' -- defined as lasting at least four weeks with symptoms on most days -- my first choice is intranasal corticosteroids," Meltzer says. "For people with an intermittent problem, antihistamines work well."

Meltzer notes that another head-to-head clinical trial is also pitting Astelin against Zyrtec. He would not be surprised if the next time, with different patients, there are different results. But the most important point, he says, is not that one antihistamine does slightly better than another.

"What is important is in 2005 there are good treatments available for seasonal allergy," Meltzer says. "Nobody has to suffer. It's like going to Baskin-Robbins -- you have a lot of good options."

By Daniel J. DeNoon, reviewed by Charlotte E. Grayson, MD

SOURCES: Corren, J. Clinical Therapeutics, May 2005 online edition; vol 27. Jonathan Corren, MD, medical director, Allergy Research Foundation Inc., Los Angeles; associate clinical professor of medicine, University of California, Los Angeles. Eli O. Meltzer, MD, co-director, Allergy & Asthma Medical Group and Research Center, San Diego; clinical professor of pediatrics, University of California, San Diego.