Epinephrine is another word for adrenaline, one of the body's three primary stress hormones. This hormone is released by the brain when the body is in a fearful or stressful situation, in a reaction that is often referred to as an "adrenaline rush." Read on to learn more about how and why epinephrine is produced by the body as well as how it is used medicinally.
Epinephrine in the Body
When a person experiences strong emotions, such as fear or anger, the part of the brain called the medulla secretes small amounts of epinephrine from the adrenal glands. This hormone is a key player in preparing the body for the natural fight or flight response that occurs in response to a perceived threat.
Epinephrine increases heart rate, blood pressure, and metabolism, provides additional muscle strength, and enlarges the pupils. All of these physical reactions prepare the body for strenuous activity as a way to make sure a person can face whatever is causing the emotional response he or she is experiencing. Production and release of epinephrine typically happens within two to three minutes of a stressful event and subsides when the situation ends. If a person has chronic stress, too much adrenaline may be produced and cause unwanted side effects, such as insomnia or nervousness.
Epinephrine in Medicine
Epinephrine has three main medical uses. If a person is experiencing a heart attack, an injection of this hormone will increase blood pressure, which helps maximize blood flow to the coronary arteries. While this helps reduce the effects of cardiac arrest, side effects may include heart or brain damage.
Allergic reactions sometimes produce anaphylactic shock, which occurs when the heart is unable to pump enough blood through the body. As with a heart attack, an injection of epinephrine can often speed up blood pressure enough to increase blood flow to a safe level. People with severe allergies often carry epinephrine with them in an injectable device known as an Epi-Pen. An epinephrine injection can also provide temporary relief during an asthma attack by widening the airways and alleviating shortness of breath, coughing, and wheezing.
Again, because of the risk for heart and brain damage, hospitalization is necessary during or immediately after an epinephrine injection. While this is a lifesaving measure, it is often not the best treatment if less invasive measures are available. Other side effects of this drug may include difficulty breathing, uncontrollable shaking, weakness, nausea, pounding heartbeat, sweating, dizziness, and anxiety.
