With cold and flu season fast approaching, two University of Florida pharmacy researchers are calling on the Food and Drug Administration to remove a common over-the-counter decongestant from the market.
Phenylephrine is an FDA-approved drug found in many over-the-counter cough, cold and allergy products intended to relieve nasal sinus congestion. But in an editorial published in the September - October, 2015, issue of The Journal of Allergy and Clinical Immunology: In Practice, Randy Hatton, Pharm.D., a clinical professor of pharmacotherapy and translational research, and Leslie Hendeles, Pharm.D., a professor of pharmacotherapy and translational research and professor of pediatrics, conclude that oral phenylephrine is ineffective at treating nasal congestion.
The editorial accompanies research findings published in the same journal from a study led by Eli Meltzer, M.D., of the Allergy & Asthma Medical Group & Research Center in San Diego. The study found that phenylephrine is no more effective than placebo in easing nasal congestion caused by allergies in adults. The study, which evaluated 539 adults with seasonal allergic rhinitis during seven days of treatment, failed to identify a dose of phenylephrine in the range of 10 to 40 milligrams that was significantly more effective than placebo. The FDA recommends taking 10 milligrams of this non-prescription decongestant every four hours for temporary relief from nasal congestion.
"Scientific evidence continues to show that the most popular products on the market containing phenylephrine are ineffective," Hendeles said. "Patients who seek an over-the-counter remedy should get what they pay for: an effective and safe alternative to a prescription drug."
Phenylephrine gained popularity in the mid-2000s after federal legislation restricted the sale of pseudoephedrine-containing products. Congress moved pseudoephedrine products such as Sudafed behind the counter to curb the drug's wide spread misuse in making illegal methamphetamine. Prior to this, oral phenylephrine was rarely used. With phenylephrine as a popular alternative to pseudoephedrine, Hatton and Hendeles began to question its effectiveness at the 10-milligram level.
"I was director of a drug information center in a hospital at the time, and doctors and patients would call me and ask, 'What is the right dose of phenylephrine?'" Hatton said. "We did not have an answer, but we determined through scientific evidence that the 10-milligram dose was insufficient."
Hatton and Hendeles, along with Almut Winterstein, Ph.D., a professor of pharmaceutical outcomes and policy at UF, conducted a systematic analysis of previous studies and eventually petitioned the FDA to require better proof of efficacy and to reconsider the appropriate dosage of phenylephrine. The FDA convened its Nonprescription Drugs Advisory Committee and after much debate, ultimately requested a dose-response study of the treatment of nasal congestion. Hatton said Meltzer's research was long overdue and reaffirmed the position that non-prescription oral phenylephrine provided little-to-no relief of nasal congestion.
"We think the evidence supports that phenylephrine's status as a safe and effective over-the-counter product should be changed," Hatton said. "We are looking out for the consumer, and he or she needs to know that science says that oral phenylephrine does not work for the majority of people."
Instead of oral phenylephrine, Hatton and Hendeles suggest patients consider using non-prescription oral pseudoephedrine from behind the counter, nasal steroids for allergic rhinitis or topical decongestant sprays for nasal stuffiness from a cold or allergies. They contend these alternatives will ultimately provide relief to the millions of Americans who suffer from nasal congestion every year.