If you experience dizziness or drowsiness, avoid these activities. Use alcohol cautiously. Alcohol may increase drowsiness and dizziness while you are taking codeine, phenylephrine, and promethazine. Codeine is a narcotic. It is a pain reliever and a cough suppressant.
Phenylephrine is a decongestant.
Constriction of blood vessels in your sinuses and nose decreases congestion. Promethazine is an antihistamine. It blocks the effects of the naturally occurring chemical histamine in your body. Codeine, phenylephrine, and promethazine may also be used for purposes other than those listed in this medication guide. A very dangerous drug interaction could occur, leading to serious side effects.