FDA Experts Debunk Ineffectiveness of Nasal Decongestant Phenylephrine in Over-the-Counter Cold and Allergy Medicines

The leading decongestant used by millions of Americans seeking relief from a stuffy nose may not be as effective as previously believed, according to government experts who have reviewed the latest research on the drug ingredient that has long been questioned.

Advisers to the Food and Drug Administration (FDA) unanimously voted against the effectiveness of the ingredient found in popular versions of Sudafed, Allegra, Dayquil, and other over-the-counter medications.

“Recent well-conducted studies have not shown any improvement in congestion with phenylephrine,” said Dr. Mark Dykewicz, an allergy specialist at the Saint Louis University School of Medicine.

The FDA convened a panel of outside advisers to reassess phenylephrine, which became the main ingredient in over-the-counter decongestants after medicines containing the older ingredient, pseudoephedrine, were moved behind pharmacy counters due to concerns over illegal processing into methamphetamine.

The original versions of Sudafed and other medications containing pseudoephedrine remain available without a prescription, accounting for about one-fifth of the $2.2 billion oral decongestant market. The rest is made up of phenylephrine versions, sometimes labeled as “PE” on packaging.

If the FDA follows the panel’s recommendations, Johnson & Johnson, Bayer, and other drugmakers may be required to remove their oral medications containing phenylephrine from store shelves. This would likely lead consumers to switch to behind-the-counter versions of the pills or nasal sprays and drops containing phenylephrine, which are not currently under review.

The two-day meeting was prompted by researchers at the University of Florida, who petitioned the FDA to remove phenylephrine products based on recent studies showing that they were no better than placebo pills for treating congestion related to colds and allergies. The same researchers also raised concerns over the drug’s effectiveness in 2007, but the FDA allowed the products to remain on the market pending further research.

This aligns with the recommendation of FDA’s outside experts at the time, who also met to discuss the drug in 2007.

This time, all 16 members of the FDA panel unanimously agreed that current evidence does not demonstrate a benefit for the drug.

“In my opinion, this oral medication should have been removed from the market a long time ago,” said Jennifer Schwartzott, the patient representative on the panel. “Patients deserve medications that safely and effectively treat their symptoms, and I don’t believe this medication achieves that.”

The advisers largely support the conclusions of an FDA scientific review published prior to the meeting, which identified significant flaws in the 1960s and 1970s studies that were initially used to support phenylephrine’s approval. The studies were deemed “extremely small” and relied on statistical and research techniques that are no longer accepted by the FDA.

“In summary, none of the original studies meet modern standards of study design or conduct,” said Dr. Peter Starke, the lead medical reviewer at the FDA.

Furthermore, three larger, well-conducted studies published since 2016 have shown no difference between phenylephrine medications and placebos in relieving congestion. These studies, conducted by Merck and Johnson & Johnson, involved hundreds of patients.

A trade group representing nonprescription drugmakers, the Consumer Healthcare Products Association, argued that the new studies had limitations and that consumers should continue to have “easy access” to phenylephrine.

Like many other over-the-counter ingredients, phenylephrine was grandfathered into use during a comprehensive FDA review that began in 1972. It has been sold in various forms for over 75 years, predating the FDA’s regulations on drug effectiveness.

“When a product has been on the market for so long, it’s natural for us to make assumptions about its efficacy,” said Dr. Theresa Michele, who heads the FDA’s office of nonprescription drugs.

However, FDA reviewers maintain that their latest assessment reflects new insights into how phenylephrine is metabolized when taken orally. The drug is rapidly metabolized and only trace amounts reach the nasal passages to relieve congestion. It appears to be more effective when directly applied to the nose through sprays and drops.

The recent panel vote is not binding and is unlikely to have an immediate impact.

However, the negative opinion of the group opens the possibility for the FDA to remove phenylephrine from the federal list of approved over-the-counter decongestants. The FDA claims that this would eliminate unnecessary costs and delays in care associated with a drug that provides no benefit.

The FDA’s nasal decongestants drug list, or monograph, has not been updated since 1995. In the past, the process of changing a monograph has taken years or even decades, involving multiple rounds of review and public comment. However, a 2020 law passed by Congress streamlines this process, allowing the FDA to expedite the publication of new standards, doses, and labeling for nonprescription ingredients.