Does a common ingredient used in many over-the-counter cold and allergy medicines actually work to get rid of nasal congestion?
That’s the question the Food and Drug Administration will pose to a panel of outside advisers during a two-day meeting next week to re-evaluate the effectiveness of the ingredient, phenylephrine, which is found in many decongestants.
Phenylephrine was approved by the FDA for over-the-counter use in the 1970s. It comes in several forms, including liquids, pills and nasal sprays.
The committee will focus specifically on the oral formulations of the ingredient, which can be found in drugs including Sudafed PE, Vicks Sinex and Benadryl Allergy Plus Congestion.
The stakes are high, experts say, because a committee vote declaring phenylephrine ineffective as an oral decongestant could push the FDA to revoke the drug’s over-the-counter designation as “Generally Recognized as Safe and Effective,” and potentially lead to it being pulled from stores shelves. The designation, typically used for older drugs, allows drugmakers to include an ingredient in over-the-counter products without the need to file an FDA application.
Oral phenylephrine is ineffective and “should almost never be used,” said Dr. Purvi Parikh, an allergist and immunologist at Allergy & Asthma Associates of Murray Hill in New York City.
Dr. Wynne Armand, a primary care physician at Massachusetts General Hospital, said she does not prescribe the drug.
“When my patients ask for over-the-counter medications for cold symptoms, I tell them to avoid buying oral meds that have phenylephrine,” Armand said.
Allowing people to use such medications is harmful not just because they don’t work, she added, but because the drugs come with side effects including headache, insomnia and nervousness.
The FDA already appears to have changed its position on the drug.
In briefing documents posted online Thursday, FDA scientists said that although it has not found any safety issues with oral phenylephrine, their assessment of the data on the drug found that it is not effective as a nasal decongestant, even when given at high doses.
Questions about the drug’s effectiveness go as far back as 2007, when a group of pharmacists filed a Citizen Petition to pull the drug from store shelves because of evidence that it was no better than a placebo.
The pharmacists cited studies that found when taken orally, a large portion of phenylephrine is metabolized in the gut and liver before it reaches the bloodstream. This means that a very small amount of the drug actually reaches the nose to relieve congestion.
The FDA did not request that drugmakers pull the drug at that time, and instead asked for more data, including about the drug at higher doses.
The Consumer Healthcare Products Association, a group that represents over-the-counter drug manufacturers, said it is against removing oral phenylephrine from the market, adding that it is the only widely available over-the-counter oral nasal decongestant.
“CHPA urges the panel to recognize PE’s clear benefits and critical role in public health,” Marcia Howard, the group’s vice president of regulatory and scientific affairs, said in a statement referring to phenylephrine. Removing the drug from the market could cause people to delay or forgo treatment, she said.
Other oral decongestants are available, though they can be less accessible. Pseudoephedrine, found in Sudafed, is available without a prescription, but in 2006 it was moved behind the pharmacy counter to prevent people from buying large quantities of the drug, which can be used to make meth. This means that people who want to buy Sudafed need to ask a pharmacist for it.
“Sudafed does work for a few days, but not in the long run,” Parikh said.
The FDA is not questioning the effectiveness of nasal spray phenylephrine.
Parikh said that it may improve symptoms temporarily, but she advised that people use nasal spray phenylephrine only for several days. After that, it can become ineffective and have rebound effects that make congestion worse.
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