What took the Food and Drug Administration so long to determine that a common cold and allergy drug does not work? Phenylephrine (PE) is almost 100 years old, having received a patent in 1927. Its effectiveness has been questioned for years. In fact, a 2007 meeting at the FDA produced data suggesting phenylephrine is barely absorbed into the body and that “PE is not more effective than placebo” (FDA Briefing Document, Efficacy of Oral Phenylephrine as a Nasal Decongestant, Sept. 11 and 12, 2023).
What Is Phenylephrine (PE)?
One of the most common ingredients in over-the-counter cold and allergy medications is the decongestant phenylephrine. It is found in more than 250 products including Sudafed PE, Tylenol Sinus and Headache, Theraflu Severe Cold Relief, Advil Sinus Congestion and Pain, Nyquil SEVERE Cough Cold and Flu Nighttime Relief Liquid, and Mucinex Sinus Max. According to the FDA, 242 million OTC bottles and packages of cough, cold and allergy products containing phenylphrine are sold annually.
We are talking beaucoup bucks! The FDA estimates that annual sales of PE-containing oral products amounts to $1.763 billion. And that is likely an underestimate. The FDA admits that it does not take into account sales in convenience stores, specialty stores, internet sales, kiosk sales or sales from Costco.
Phenylephrine is classified as a decongestant. That means it is supposed to constrict blood vessels. I emphasize the words “supposed to” because there have been real doubts that it actually works.
When you have a cold or allergies, there is inflammation within the nasal passages. That is a natural response to infection or allergens. An effective decongestant would theoretically shrink the small blood vessels in the nose, reduce congestion and improve breathing.
The People’s Pharmacy (1976)!
Please step into my time machine. I was writing the first edition of the book, The People’s Pharmacy (St. Martin’s Press, 1976) 50 years ago.
Here is what I said about phenylephrine way back then:
“Well, what about the decongestant? The most common ingredient is something called phenylephrine. Though it might work if given in a sufficient dose (more than forty milligrams), most nonprescription cold medications have less than half that amount. According to Consumer Reports, ‘the oral dose in two Dristan tablets is only one-fourth of the dosage found to be ineffective in controlled clinical testing.’”
So here we are, 50 years later, and the Food and Drug Administration has finally decided that the main ingredient in OTC cold and allergy decongestants is worthless. Never mind that billions of dollars have been spent over all that time. Never mind that the FDA insists all the drugs it approves are “safe and effective.” We’re just supposed to pretend that this is not a giant FDA ooops.
A chemist that I admire, Derek Lowe, PhD, wrote an article last year (Science, March 30, 2022) titled “The Uselessness of Phenylephrine.” Dr. Lowe is no anti-drug crusader. He has worked for a number of major pharmaceutical companies.
Here is what he had to say about the 10mg oral dose of phenylephrine:
“…here in the US, if you go to the drugstore and purchase an over-the-counter nasal decongestant (as a single agent or a combination of drugs that includes a decongestant), you will in every single case be buying phenylephrine. Which does not work. It is found in 261 different OTC products, and it is a useless bait-and-switch on the consumer in every one of them. I have always told friends and family members to avoid these products if at all possible, and to go back to the pharmacy counter to get something that actually works.”
What Actually Works As An Oral Decongestant?
The answer is straightforward: pseudoephedrine. It is…surprise, surprise…derived from the plant Ephedra sinica. Healers in China have been using ephedra (aka ma-huang) for thousands of years. Doctors in the US prescribed the drug ephedrine for decades to treat asthma. That was before modern bronchodilators became available.
For years, over-the-counter oral Sudafed contained pseudoephedrine as its main ingredient.
Dr. Lowe stated in his article above that:
“It is famous for drying nasal passages during colds and allergies, at which it excels. Some people still notice amphetamine-like effects of sleeplessness and jitters at those doses, and at higher doses (not recommended!) pretty much everyone will. Across the board, these compounds can cause other CNS symptoms, increased blood pressure, loss of appetite, cardiac effects, difficulty urinating and more, but the window for these does seem to be widest with pseudoephedrine.”
In other words, pseudoephedrine does shrink blood vessels in the nose. That means it actually is an effective decongestant. But, as noted, there can be side effects. And you probably noticed the phrase “amphetamine-like effects.”
Because this drug can be used to make methamphetamine, pseudoephedrine-containing products are now only sold behind the counter. Anyone who wants an effective oral decongestant with this ingredient will need to ask the pharmacist.
Here is what the FDA says about purchasing pseudoephedrine:
“The Combat Methamphetamine Epidemic Act of 2005 has been incorporated into the Patriot Act signed by President Bush on March 9, 2006. The act bans over-the-counter sales of cold medicines that contain the ingredient pseudoephedrine, which is commonly used to make methamphetamine. The sale of cold medicine containing pseudoephedrine is limited to behind the counter. The amount of pseudoephedrine that an individual can purchase each month is limited and individuals are required to present photo identification to purchase products containing pseudoephedrine. In addition, stores are required to keep personal information about purchasers for at least two years.”
What Will Happen to Products with Phenylephrine?
First, the FDA has not taken any action! Although its “advisory panel” has unanimously agreed that phenylephrine is ineffective, the agency itself has not made any decisions about what to do with OTC products containing PE. A trade group representing the OTC pharmaceutical industry might very well contest any decision to remove popular cold, cough and allergy products from shelves because of an ineffective decongestant ingredient.
So, the bottom line is that you should not hold your breath waiting for the Food and Drug Administration to jump into action. Remember, I wrote that phenylephrine was ineffective 50 years ago in my very first book, The People’s Pharmacy.
If the FDA actually requires dozens of drug companies to reformulate their popular cough, cold and allergy meds, it could take years to implement. Goodness knows, the FDA would probably not want those companies to lose billions of dollars because a key ingredient is worthless.
What About Other OTC Drugs?
Is phenylephrine an anomaly? Could there be other ingredients in over-the-counter pharmaceuticals that are also ineffective?
An article in The Atlantic (Sept. 13, 2023) offers this food for thought:
“In any case, phenylephrine is not the only cold-and-flu drug with questionable effectiveness in its approved form. The common cough drugs guaifenesin and dextromethorphan have both come under fire. But we lack the robust clinical-trial data to draw a definitive conclusion on those one way or the other.”
That does not mean the dextromethorphan (DM) in scores of cough and cold medicines is ineffective, but it does point out that the data have not been overwhelming. And there are also questions about the effectiveness of the expectorant guaifenesin.
What Do You Think?
Are you surprised that it has taken the FDA so long to recognize an ingredient in hundreds of popular OTC cough, cold and allergy products is ineffective? Do you think the FDA will investigate DM-containing cough meds any time soon?
What about home remedies for colds, coughs and allergies? Do you have a favorite? As mentioned in our eGuide, chicken soup remains one of our favorites! You may also find our article about “How to Make Onion Syrup for a Cough” of interest. And our all-time favorite article on coughs is:
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