Mixing Guaifenesin and Alcohol
No drug interactions exist between alcohol and guaifenesin. However, that does not mean it is a good idea to combine them.
Generally, a person taking guaifenesin is trying to treat respiratory symptoms and thin out secretions from a cough or cold. Alcohol can weaken the immune system for up to 24 hours, which can worsen respiratory symptoms while someone is fighting off an infection. For this reason, alcohol has been linked to an increased risk of respiratory infections like pneumonia. Further, alcohol-induced nasal symptoms like nasal stuffiness and runny nose can occur, especially in women and with wine consumption. As a result, drinking can counteract any effect guaifenesin may have on nasal secretions and worsen your infection.
Alcohol and Mucinex D
Mucinex D combines guaifenesin with pseudoephedrine, a decongestant that shrinks blood vessels in the nose to make breathing easier. Although there are no drug interactions between alcohol and guaifenesin or pseudoephedrine, it is not a good idea to drink while taking Mucinex D. Aside from alcohol’s impact on the immune system and nasal stuffiness, drinking can also counteract pseudoephedrine. Within ten minutes of drinking, alcohol tricks your body into feeling warm. This causes your blood vessels to expand in an attempt to cool yourself down. However, this blood vessel dilation negates the vessel-shrinking effects of pseudoephedrine.
Alcohol and Robitussin DM
Medications like Robitussin DM and Mucinex DM combine guaifenesin with dextromethorphan, a cough suppressant. Dextromethorphan has a drug interaction with alcohol. Taking the substances together can increase side effects like dizziness, drowsiness and concentration problems. Further, some people take high doses of dextromethorphan in an attempt to get high. Mixing large quantities of dextromethorphan with alcohol can be deadly. This is especially true in Caucasians — up to 10% have problems breaking down dextromethorphan, leading to high levels in the body.