Mucinex products help with sinus congestion through their active ingredients of pseudoephedrine, phenylephrine and oxymetazoline. These medications are nasal decongestants that work by shrinking inflamed mucous membranes inside the nose, as Mucinex's official website explains.
Nasal decongestants shrink mucous membranes in the nose by constricting blood vessels, according to Drugs.com and MedlinePlus. Mucus can drain more easily once these membranes shrink, explains Mucinex's website.
The potential side effects of pseudoephedrine include allergic reaction, dizziness or anxiety, fast or uneven heartbeat, very high blood pressure, and easy bruising or bleeding, according to Drugs.com. Patients who experience these side effects should stop using the medication and seek medical attention.
Potential side effects of phenylephrine are nervousness, dizziness and sleeplessness, as listed by MedlinePlus. Patients who experience these side effects or any other unusual problems should stop using the medication and seek medical advice.
The side effects of oxymetazoline include stinging, burning, sneezing and increased nasal discharge, according to Drugs.com. Patients who experience an allergic reaction to oxymetazoline should seek immediate medical attention.
Patients should follow the instructions of a physician or the instructions on the label when taking these decongestants, as Drugs.com and MedlinePlus advise. Patients should not use oxymetazoline for more than three days unless directed to do so by a physician. Children younger than 4 years should not take pseudoephedrine or phenylephrine, and children younger than 6 years should not take oxymetazoline.