Virtussin A/C is a medicine used in the treatment of cough and nasal congestion. In this way, Virtussin A/C is commonly used in the treatment of colds and flu. The medicine contains three active ingredients - codeine, guaifenesin, and pseudoephedrine - each of which plays a complementary role in combating cold and flu-like symptoms.
Codeine, for example, is an opioid that reduces pain and relieves cough. Guaifenesin, in contrast, is used to expel phlegm from the airways, facilitating effective breathing. It also helps to relieve cough. It is thought to be an NMDA receptor antagonist. Pseudoephedrine is a nasal decongestant, achieving this effect by acting at alpha-adrenergic receptors and producing vasoconstriction.
Common side effects with Virtussin A/C include constipation, dizziness, headache, weakness, nausea, and drowsiness.