Aspirin is a pharmaceutical drug often used to treat pain, fever, and inflammation. A drug is any substance (other than food that provides nutritional support) that, when inhaled, injected, smoked, consumed, absorbed via a patch on the skin, or dissolved under the tongue causes a physiological change in the body.
In a crisis, the sympathetic division of your autonomic nervous system (ANS) mobilizes your body for action, directing your adrenal glands to release the stress hormone epinephrine (adrenaline) and norepinephrine (noradrenaline). To provide energy, your liver pours extra sugar into your bloodstream.
Medical Definition of Sympathetic nervous system. Sympathetic nervous system: A part of the nervous system that serves to accelerate the heart rate, constrict blood vessels, and raise blood pressure. The sympathetic nervous system and the parasympathetic nervous system constitute the autonomic nervous system. Last Editorial Review: 5/13/2016.