The active ingredient in Vicks Formula 44 is dextromethorphan hydrobromide. This ingredient is commonly used as a cough suppressant for minor irritations of the airways, such as those associated with sinusitis or the common cold, according to its label.
Dextromethorphan hydrobromide decreases the feeling of needing to cough and should not be used to treat ongoing coughs or coughs with mucus, according to WebMD.
Vicks Formula 44 is only for short-term relief, and any cough that lasts longer than seven days warrants a visit to the doctor, especially if it occurs with a fever, rash or lasting headache, explains its label. This medicine mustn't be taken with monoamine oxidase inhibitors, such as antidepressants.