Common decongestant used in Nyquil and other drugs doesn’t relieve congestion, FDA says

The ingredient used in common oral decongestants like Sudafed, Allegra, Dayquil, and Nyquil doesn’t provide relief, advisers to the Food and Drug Administration (FDA) said Tuesday.

The Nonprescription Drug Advisory Committee (NDAC) met to discuss the efficacy of phenylephrine as a nasal decongestant on 11 September and 12 September. They reviewed the available data on the subject and, in a unanimous vote, signalled that it does not work any more than a placebo might, according to the Associated Press.

The FDA has been looking into the topic since December 2007, according to a briefing released ahead of the 12 September meeting.

In the past, phenylephrine was thought to relieve congestion caused by allergies, colds and hay fever, per the National Institutes of Health (NIH). It was recommended to treat pressure and congestion and was thought to work by reducing swollen blood vessels in the nasal passages. It comes in tablet or liquid form, or as a strip that is dissolved in the mouth. Usually, it’s recommended to take every four hours as needed.

The NDAC briefing provided evidence that shows that when phenylephrine is taken orally, not much of it actually reaches the nose.

Peter Starke, the FDA official who led the review of phenylephrine, said older research on the ingredient hasn’t held up. “In conclusion, we do believe that the original studies were methodologically unsound and do not match today’s standard,” he said, per NBC News. “By contrast, we believe the new data are credible and do not provide evidence that oral phenylephrine is effective as a nasal decongestant.”

The Consumer Healthcare Products Association (CHPA) released a statement Tuesday countering the NDAC’s decision. “We are disappointed by the outcome of today’s FDA Advisory Committee meeting because its…recommendation is at odds with numerous clinical trials and previous regulatory determinations affirming oral phenylephrine (PE) as a safe and effective decongestant at its labeled dose,” CHPA president and CEO Scott Melville said in the statement. The statement went on to suggest that previous research on the ingredient may have been “inappropriately dismissed and discounted”.

But experts said there isn’t sufficient evidence to recommend it. “Modern studies, when well conducted, are not showing any improvement in congestion with phenylephrine,” Mark Dykewicz, an allergy and immunology specialist at Saint Louis University School of Medicine, told the Associated Press.

Phenylephrine generated about $1.8bn in sales in 2022, and it’s the most popular oral decongestant in the US, according to reporting from NBC News. (When used in a nasal spray, phenylephrine is still thought to provide at least temporary relief.)

If the FDA ultimately sides with the NDAC’s vote, large pharmaceutical companies including Johnson & Johnson and Bayer will be required to pull oral medications that contain phenylephrine from pharmacy shelves.

The briefing noted that the NDAC’s vote against phenylephrine could cause significant issues to companies that produce decongestants that use the ingredient. “Should the Agency take an action regarding the [safety and effectiveness of] oral phenylephrine, we also understand that a significant impact on industry would be inevitable,” it said. “Manufacturers, warehousers, and pharmacies all have a significant supply chain investment in stocks of PE, either as a precursor chemical, ingredient itself, or in a finished product.”

In addition to being ineffective, phenylephrine has been linked with worrisome side effects, including nervousness, sleeplessness, and dizziness, per the NIH.