Cof Off Expectorant works through the combined effects of its active ingredients:

• Diphenhydramine is an antihistamine. It helps reduce coughing caused by irritation or allergies and can also dry up excess nasal secretions. It may also cause drowsiness.
• Ammonium chloride is an expectorant. It helps loosen and thin mucus in the airways, making it easier to cough the mucus out.
• Menthol provides a cooling sensation in the throat and can help soothe irritation, making coughing less uncomfortable.