Diphenhydramine/Phenylephrine-containing Syrup

**Semantic type:** Pharmacologic Substance

**Definition:** A cough and cold syrup containing the first-generation antihistamine diphenhydramine hydrochloride and the decongestant phenylephrine hydrochloride. Diphenhydramine blocks the effects of histamine, thereby preventing symptoms such as sneezing and itchy, watery eyes, runny nose and sore throat. In addition, this agent causes drowsiness and can be used as a sleep aid. Phenylephrine, a sympathomimetic agent, acts as a decongestant by inducing vasoconstriction mediated via alpha-adrenergic receptors. This reduces blood flow, decreases swelling and prevents nasal and sinus congestion.

**Synonyms:** - Triaminic Night Time Cold and Cough