Ammonium chloride increases acidity by increasing the concentration of hydrogen ions. It can be used as an expectorant due to its irritative action on the bronchial mucosa. Menthol exerts soothing and counter-irritant effects on upper respiratory mucosa. Menthodex cough mixture contains expectorant and demulcent agents for the treatment of coughs and colds. It makes the cough more productive by loosening tenacious bronchial mucus. It combats the congestive symptoms that frequently accompany coughs and colds and reduces bronchial and nasal congestion.