Promethazine VC is a prescription cough syrup used to relieve upper respiratory symptoms, such as nasal congestion associated with colds and allergies. The medication is absorbed through the gastrointestinal tract. Its clinical effects become apparent about 20 minutes after ingestion and usually last between four to six hours.
Promethazine VC may impair the physical or mental abilities required for the safe operation of machinery or motor vehicles. The accompanying use of central nervous system depressants such as alcohol, general anesthetics or tranquilizers will amplify the impairment. The medication may also cause a potentially fatal respiratory depression in patients suffering from chronic obstructive pulmonary disease or sleep apnea, and its use should be avoided in such cases.