A panel of advisers convened by the Food and Drug Administration (FDA) has unanimously determined that the widely-used decongestant ingredient, phenylephrine, lacks effectiveness in treating nasal congestion, according to the Associated Press.
Phenylephrine is a key component in many over-the-counter medications designed to alleviate congestion, including popular brands such as Sudafed and Dayquil. Its prominence grew following a 2006 law that restricted access to the older decongestant, pseudoephedrine, due to its potential use in the production of methamphetamine.
Questions about the oral efficacy of phenylephrine in relieving nasal discomfort have arisen on multiple occasions, including a previous inquiry in 2007. At that time, the FDA allowed these medications to remain on store shelves pending further research. However, the recent findings may prompt the FDA to request drug manufacturers, including Johnson & Johnson and Bayer, to remove these oral medications from the market.
Although the FDA’s potential decision could lead to the removal of phenylephrine from the list of federally approved decongestants in pill and liquid forms, it’s important to note that the panel’s vote is a recommendation and not a binding decision. As a result, consumers are unlikely to experience immediate changes in product availability.
Despite the continued presence of phenylephrine versions of these drugs, multiple studies have previously shown that it offers no discernible benefits beyond what a placebo can provide.
Phenylephrine is intended to relieve nasal congestion, nasal pressure, and stuffiness often associated with colds or allergies. It purportedly achieves this by stimulating alpha-1 adrenergic receptors in nasal arteries, causing the constriction of dilated blood vessels in the nasal passages. This action is meant to prevent fluid from the blood vessels from accumulating in the nasal tissues, thereby alleviating congestion. Phenylephrine can also be employed to raise blood pressure when administered in a specific manner.
The transition of phenylephrine to the primary decongestant in over-the-counter medications occurred in 2006 due to concerns about pseudoephedrine’s potential misuse in methamphetamine production.
Numerous products on the market target multiple symptoms, such as cold and flu medications that address fever, headache, and congestion. The presence of phenylephrine in these products does not affect the efficacy of other ingredients intended to treat different symptoms.
Common products containing phenylephrine include Sudafed PE, Mucinex, Sinex, Dayquil, Benadryl, Tylenol Sinus, Advil Sinus Congestion, Lusonal, as well as various store brands such as Equate, Kroger, Walgreens, and CVS.
It’s essential to be aware that some of these products offer multiple versions, some with phenylephrine and others with the older ingredient pseudoephedrine. Therefore, it’s crucial to check the label for active ingredients.
The primary distinction between the two ingredients lies in their efficacy when taken orally. Pseudoephedrine (PDE) has been proven effective in treating congestion when ingested, whereas phenylephrine (PE) has not demonstrated the same effectiveness.
Several factors contribute to this discrepancy:
Metabolism: Phenylephrine and pseudoephedrine are metabolized differently. Only about 40% of an oral dose of phenylephrine reaches the bloodstream after gut wall metabolization, while pseudoephedrine is absorbed differently, with approximately 100% of the dose entering the bloodstream.
FDA Approval: Phenylephrine received FDA approval based on studies conducted by pharmaceutical companies themselves, rather than clinical trials.
Misuse Risk: Due to its potential for use in methamphetamine production, pseudoephedrine is more prone to misuse than phenylephrine. While not addictive on its own, pseudoephedrine can produce central nervous system effects such as insomnia.
Central Nervous System Effects: Pseudoephedrine more frequently leads to stimulating effects on the central nervous system, including symptoms like insomnia, primarily due to its differing chemical structure compared to phenylephrine.
These findings raise questions about the continued use of phenylephrine in over-the-counter medications and the need for alternatives to effectively address nasal congestion.