Definition: Phenergan An antihistamine drug with sedative properties, containing promethazine. A to Z Index of Drugs: A B C D E F G H I J K L M N O P Q R S T U V W Z Search Drug Terms: You can enter any word or drug name above to seach the database (e.g. cannabis or trip) Caffeine Drinks Full Definition of 'Phenergan' An Antihistamine drug with Sedative properties, containing Promethazine. Go to Drugs A-Z homepage More Information Reducing Harm The Law And UK Drug Classifications How Do Drugs Work? Effects Of Drugs On The Brain? Drugs And Pregnancy Risks Snorting Injection Ingestion Smoking Drug Terms DAN 24/7 Contact Us About US Accessibility Policy Privacy Policy Disclaimer