Phenergan Syrup 100 ml is a prescription antihistamine medicine commonly used in the UK to help manage difficulty sleeping (insomnia), restlessness, and night-time allergies. Containing promethazine hydrochloride, it works by blocking histamine in the body and producing a natural sedative effect, which helps you fall asleep faster and enjoy more restful nights. https://zopiclonemeds.co.uk/product/phenergan-syrup-100ml-pack-of-5/