"beta blocker." YourDictionary, n.d. Web. 11 October 2018. <http://www.yourdictionary.com/beta-blocker>.
beta blocker. (n.d.). Retrieved October 11th, 2018, from http://www.yourdictionary.com/beta-blocker
A drug that blocks beta-receptors, thus counteracting the excitatory effects of norepinephrine and other beta-agonists released from sympathetic nerve endings. Beta-blockers are used primarily to treat angina, hypertension, arrhythmia, and migraine. Also called beta-adrenergic antagonist . Also called beta-adrenergic blocker .