There's growing evidence that an ingredient in many cold medicines isn't relieving congestion.
Phenylephrine has been proven to be safe, but at least four studies have found that it's not effective in relieving congestion.
Jonathan Bernstein, a researcher at the University of Cincinnati College of Medicine, said the problem has to do with how the medicine is administered.
"It's just when you swallow it, and it goes into the gut that there's an enzyme there that inactivates it, and it doesn't get into the bloodstream," he said.
Bernstein is petitioning the Food and Drug Administration to have phenylephrine removed from the market when it's in medicines that are administered orally.
The FDA said it's still reviewing the petition.
Bernstein believes this is a low-priority issue for the FDA because the ingredient is not toxic.
Citing research, the American Academy of Allergy, Asthma and Immunology and the American College of Clinical Pharmacy have also come out in support to ban the pills.
"It's an economic waste for people to buy these remedies," Bernstein noted. "It's they're not going to be effective. It's going to delay care that more effective therapies could be used to manage their conditions."
The Consumer Healthcare Products Association defends the use of phenylephrine, saying, the "FDA has recognized that phenylephrine is a safe and effective oral nasal decongestant," adding that its members continue to comply with regulations that apply to the ingredient.
Studies have found phenylephrine through a nasal spray is effective.
Nasal sprays with the ingredient are available over the counter. It's still recommended that people talk with their doctor before taking medications.