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Compare Dextromethorphan vs. Guaifenesin

Head-to-head comparisons of medication uses, side effects, warnings, and more.

Key takeaways

Dextromethorphan (Delsym) and guaifenesin (Mucinex) are both over-the-counter medications used to treat coughs, but they work in different ways. Dextromethorphan is an antitussive, which means it suppresses the cough reflex to help relieve a dry cough. Guaifenesin, on the other hand, is an expectorant that helps loosen mucus in the airways, making it easier to cough up and clear chest congestion. Dextromethorphan is available in both extended-release and immediate-release forms, while guaifenesin can be found in immediate-release tablets and liquid solutions. Guaifenesin is also available in an extended-release formulation (Mucinex ER). Dextromethorphan can cause side effects like nausea and drowsiness, and it can interact with certain medications, leading to serious conditions like serotonin syndrome. Guaifenesin generally has fewer side effects, but it can cause nausea and dizziness in some cases. Both medications should be used carefully to avoid accidental overdose, especially since they are common ingredients in many combination products.

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