An FDA medical advisory panel ruled that phenylephrine (PE), a key ingredient in many over-the-counter cold medications, does not actually work to treat nasal congestion when taken orally at the recommended 10 mg dose every 4 hours. Phenylephrine was last evaluated for over-the-counter use as an oral and intranasal decongestant in 1976, according to the panel. If you're keeping score at home, that means many of the OTC decongestants consumers