Side Effects Of Mucinex DM Cough Suppressant

Mucinex DM cough suppressant (dextromethorphan-guaifenesin) is an over-the-counter cough remedy for children and adults. By affecting signals in the brain that initiate a cough reflex, the medicine works to suppress coughs. It is also an expectorant, helping to loosen chest congestion and making coughs more productive. Mucinex DM is not formulated to treat coughs related to asthma, smoking or emphysema, according to, and may cause certain side effects in some individuals.

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Allergic Reactions

Allergic reactions are possible with most medications, including Mucinex DM cough suppressant. Side effects of an allergic reaction can seem mild, causing rashes or hives, but these reactions can become severe, leading to difficulty breathing, hallucinations and swelling of the face, tongue, lips or throat. This type of reaction is known as anaphylaxis, a potentially life-threatening medical emergency occurring within seconds or minutes of exposure to an irritant and requiring immediate medical attention, according to the Mayo Clinic.

Headache & Impaired Thinking

Headaches or dizziness is a mild side effect that may occur with Mucinex DM cough suppressant. In addition, the drug may cause impaired thinking and reactions, making some tasks, like driving, operating a machine or other tasks that require focus and concentration, potentially dangerous. Drinking alcohol can increase these risks and other side effects, and should be avoided, according to

Upset Stomach/Nausea

Mucinex Dm cough suppressant can cause some individuals to experience upset stomach, nausea or vomiting.

Safety and Drug Interactions

Drug interactions can occur with the use of Mucinex DM and other medications. Cough or cold medicines should not be used with MAO inhibitors like Emsam, Marplan, Nardil, Azilect, Parnate and Eldepryl. If these drugs have been used within fourteen days, traces may still be present in the body, causing adverse reactions. In addition, Mucinex DM may not be appropriate for pregnant women or those who are breastfeeding, as the side effects are unknown and it is undetermined whether the medication can be passed through a nursing mother's breast milk. Always talk to a doctor or pharmacist for safety instructions.

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