8b85b910_d_s_Flow___Scientific_American__2
[0] Beta-blockers [1] Propranolol, Carvedilol, Atenolol [3] Doctors often prescribe beta-blockers off label for people with anxiety disorders, and actors and musicians sometimes take them to calm stage fright. In addition, a recent study suggests that beta-blockers may reduce the risk of dementia by releasing the overly tight blood vessels in the brain. Beta-blockers can also cause side effects of fatigue, insomnia and, potentially, depression. [2] 
Beta-blockers prevent the stress hormone epinephrine from binding to receptors in the nervous system. Typically, epinephrine triggers the “fight or flight” response, which causes blood vessels to contract to pump more blood to the heart.
Common Prescription Drugs Alter Blood’s Flow - Scientific American
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