Phenylpropanolamine is a psychoactive drug of the phenethylamine and amphetamine chemical classes which is used as a stimulant, decongestant, and anorectic agent. It is commonly used in prescription and over-the-counter cough and cold preparations. In veterinary medicine, it is used to control urinary incontinence in dogs under trade names Propalin and Proin. Phenylpropanolamine acts as a potent and selective releasing agent of norepinephrine and epinephrine, or as a norepinephrine releasing agent (NRA). Many sympathetic hormones and neurotransmitters are based on the phenethylamine skeleton, and function generally in "fight or flight" type responses- such as increasing heart rate, blood pressure, dilating the pupils, increased energy, drying of mucous membranes, increased sweating, and a significant number of additional effects.