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Mucinex DM vs. Delsym

Mucinex DM (guaifenesin / dextromethorphan) is an over-the-counter medication that's used to relieve cough and loosen mucus. It has two active ingredients: guaifenesin (an expectorant that clears chest congestion) and dextromethorphan (a cough suppressant that relieves cough). The medication is available as tablets, dissolvable granules, and liquid that are taken by mouth, each with different dosages, directions, and age limits. Extended-release tablets are taken every 12 hours, while the other forms are usually taken every 4 hours. Most people have few to no side effects when used as directed, but it can sometimes cause stomach upset, dizziness, and drowsiness.

• Short-term relief of coughs caused by minor throat or lung irritation (e.g., common cold)
• Loosens and breaks up mucus in the airways (chest congestion)

• Side effects aren't common. See Other Side Effects.

• Risk of overdose and misuse
• Interactions with certain medications for Parkinson's disease and depression
• Caution use in people with phenylketonuria (PKU) - dissolvable granules only

Dextromethorphan (Delsym) is an over-the-counter cough suppressant (antitussive). It helps relieve "dry" cough in adults and children by suppressing the cough reflex. Dextromethorphan (Delsym) is available as an extended-release (ER) cough syrup that's taken by mouth, typically every 12 hours. It also comes as an immediate-release (IR) caplet that's usually taken every 6 to 8 hours. Dextromethorphan might also come in additional formulations, under other brands. Some common side effects of dextromethorphan (Delsym) include nausea and stomach upset. Rarely, it can also make you sleepy.

• Short-term relief of cough caused by minor throat or lung irritation (e.g., common cold)

• Nausea
• Belly discomfort

• Overdose and misuse
• Medication interactions