Healthnotes Newswire (November 16, 2006)—Hay fever sufferers can get better relief and save money, according to a study that found one week of Benadryl treatment to be more effective than Clarinex for treating hay fever symptoms, including stuffy nose.

In 14 medical centers throughout the continental United States, 610 people with moderate to severe hay fever (seasonal allergic rhinitis) were randomly assigned to take Benadryl (diphenhydramine; 50 mg three times a day), Clarinex (desloratadine; 5 mg once a day), or a placebo for one week. Benadryl was found to work better than either Clarinex or placebo for treating runny nose, red and watery eyes, sneezing, itching, and stuffy nose due to hay fever, while Clarinex was better than placebo only for relief of sneezing.

Until now, it has commonly been believed that treating hay fever required both an antihistamine and a decongestant, like Sudafed (pseudoephedrine), to relieve the stuffy nose. This study shows that Benadryl, unlike Clarinex, relieves hay fever symptoms including stuffy nose without the addition of a decongestant.

However, Benadryl users also had more side effects, including 22% who reported drowsiness, compared with 4.5% of those who used Clarinex and 3.4% of those who took placebo.

These findings, published in the Annals of Allergy, Asthma & Immunology, suggest that Benadryl is a good choice for hay fever relief at bedtime or when drowsiness is not a concern. However, during the day and at other times when it is important to be alert, Sudafed alone or in combination with a nondrowsy antihistamine, such as Clartin or Clarinex, is a safer choice.

Benadryl and Sudafed are available over the counter, while Clarinex is available only by prescription. Claritin, which is closely related to Clarinex and causes little drowsiness, is also available over the counter.

It should be noted that the study was paid for by Pfizer, Inc., the company that makes Benadryl.

(Ann Allergy Asthma Immunol 2006;96:606–14)