Do Over-The-Counter Cold Medicines Really Work?

Cold and flu season will see millions of Americans sniffling their way through the drugstore aisles in search of something to help ease their misery. We spend $8 billion a year on over-the-counter cold medicines. But a recent study finds the active ingredient in many nasal decongestants commonly taken for colds is no more effective than a placebo.

The study, published in the Journal of Allergy and Clinical Immunology: In Practice, looked at the effectiveness of phenylephrine hydrochloride (PE HCl), widely used in over-the-counter treatments for nasal congestion. The study involved 539 adults with symptoms of nasal congestion from seasonal allergies. Participants were given different doses of PE HCl or a placebo for 7 days. The researchers found that when taken orally in FDA-approved doses of up to 40 mg every 4 hours, the drug proved no better than a sugar pill at relieving symptoms.

If you remember older versions of decongestants working better than what's on the shelf today, you're onto something.

"A lot of these medications used to use pseudoephedrine, a different chemical -- it's what's found in Sudafed, for example,"explained Dr. Devi Nampiaparampil, a clinical associate professor at NYU School of Medicine. That formulation was proven to be effective in previous studies.

But pseudoephedrine was being abused by people who bought it in bulk to process into meth, so in 2005 a federal law was passed adding new restrictions on its sale. Those medicines are now held behind the counter, available in limited quantities only if you provide a valid ID and signature. If you want to just grab a box of cold medicine off the shelf and go, it will be a version without pseudoephedrine.

"Instead, they've been using phenylephrine now in a lot of the over-the-counter decongestants," Nampiaparampil told CBS News. "The problem is, if it doesn't work as well, what's the point of people spending so much money on those medications and then still having the symptoms?"

She points out that previous studies have come to different conclusions and found the drugs do help, so more research is needed. "Just because it's new research doesn't mean it's better research," she said. "In the past, people thought phenylephrine was effective. So what they have to do is take out all the studies and really compare what was done in the past with what was done now."

In any case, none of these medications can actually cure a common cold. "Unfortunately, with viruses, no matter what you do, sometimes they just take their toll. You have to wait them out," Nampiaparampil said.

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