What is the X in X-mas?
synthetic drug related to morphine and used in medicine as a cough suppressant. The hydrobromide salt of dextromethorphan occurs as white crystals or a white crystalline powder, soluble in water, alcohol, and chloroform. It acts upon the central nervous system to suppress the cough reflex. The drug does not produce addiction or central depression, as do a number of other morphine derivatives, and it has no analgesic effect. For this reason it is commonly prepared in therapeutic doses in nonprescription cough syrups and tablets