Mucinex, also known as guaifenesin, is an over-the counter-expectorant. The drug thins mucus in the lungs, making it easier to expel. It is usually used for colds or allergies. Mucinex is available in regular strength, maximum strength and extended release. Children's Mucinex is also available in liquid form and mini-melts. Pseudoephedrine, a decongestant, is added to guaifenesin and is sold as Mucinex D. Side effects associated with Mucinex are rare.
Nausea and Vomiting
Mucinex can cause nausea and vomiting. Patients can reduce these side effects by taking the lowest dose possible. Taking the drug with food can also help ease nausea.
Dizziness and Headache
Mucinex occasionally causes dizziness and headache. According to Drugs.com, patients should avoid driving if dizziness occurs. Moving slowly from a sitting position to a standing position, or during any other sudden changes in position, can help avoid injuries associated with dizziness. With a doctor's permission, patients can try an over-the-counter pain medication to treat headache.
Anaphylaxis
All drugs have the potential to cause an anaphylactic or allergic reaction. Drugs.com recommends stopping guaifenesin use and seeking emergency medical attention if an allergic reaction occurs. Symptoms of an anaphylactic reaction include hives, itching, difficulty breathing and even loss of consciousness. These symptoms are usually treated at a hospital with epinephrine, which immediately stops the allergic reaction. Antihistamines and steroids are also used to decrease inflammation.
