Common OTC cold medications that include acetaminophen (Tylenol) may expose patients to dangerous phyenylephrine levels. These include medicines such as Tylenol Cold and Flu and DayQuil. When healthy volunteers took phenylephrine (10 mg) combined with acetaminophen (1000 mg) the blood concentration of phenylephrine was 2 times higher than when taking phenylephrine alone. Potential adverse effects include high blood pressure, elevated heart rate, and nervousness.
PositiveTip: Exercise caution in using even OTC cold remedies. Saline nasal rinses or simple hydrotherapy procedures may give the same relief.