Everything You Need to Know About Adrenaline (Epinephrine)

<p>SDI Productions / Getty Images</p>

SDI Productions / Getty Images

Medically reviewed by Isabel Casimiro, MD, PhDMedically reviewed by Isabel Casimiro, MD, PhD

Adrenaline, also called epinephrine, is a hormone and medication primarily used for the emergency treatment of life-threatening allergic reactions.

Adrenaline is released by the adrenal glands. It plays a key role in the body's acute (short-term) stress response by triggering the sympathetic nervous system (SNS).

The SNS affects many organs and controls the body's fight-or-flight response. In a stressful situation, adrenaline is quickly released into the blood within a few minutes. This release sends impulses to organs, prompting them to create a specific stress response.

People may need to take adrenaline if they experience a serious or life-threatening allergic reaction or if their adrenaline levels get out of balance.

Function

Adrenaline functions as a hormone in the body in a variety of ways. For example, it:

  • Stimulates the SNS to control the body's fight-or-flight reaction to physical stressors and threats

  • Increases smooth muscle contraction in the vascular system (the vessels that carry lymph fluid and blood throughout the body)

  • Stimulates the contraction of the pupillary dilator muscles in the eye, which widen the pupils to allow more light to enter the eye

  • Causes the contraction of the intestinal sphincter muscles that open and close passages in the body, including the opening of the anus and the sphincter pylori (the ring of muscle that connects the stomach and small intestine)

  • Increases heart rate and allowing contractions of the heart muscle

Adrenaline Levels

Normal adrenaline levels are 0-140 picograms per milliliter (pg/mL), or 764.3 picomoles per liter (pmol/L).

Factors that affect adrenaline levels include how the body reacts to stress or perceived dangers and certain medical conditions.

A blood or urine test can measure adrenaline levels. A healthcare provider, such as a primary care provider (PCP) or endocrinologist (a medical doctor specializing in treating hormone-related conditions), will order a catecholamine test if they suspect your symptoms may indicate lower or higher adrenaline levels.

A catecholamine test can determine levels of adrenaline and other catecholamines (hormones made by the adrenal glands) to test for or rule out certain types of rare tumors.

Low Adrenaline Levels

Low adrenaline levels are anything below 764.3 pmol/L. Low adrenaline is rare, but when it does occur, it limits the body's ability to respond normally to stress and stressful situations.

High Adrenaline Levels

High levels of adrenaline are anything above 764.3 pmol/L. Factors that cause adrenaline to rise include:

  • Certain medical conditions

  • Caffeine

  • Chronic (long-term) stress

  • Heavy exercise

  • Alcohol

  • Smoking

High adrenaline can indicate rare cancerous or benign (non-cancerous) tumors such as pheochromocytoma, an adrenal gland tumor.

Symptoms of high adrenalin include:

If adrenaline levels are too high, treatment will depend on the cause. For example, if a tumor is the cause, a healthcare provider will treat or surgically remove the tumor. If treatment is successful, then the adrenaline level should return to normal.

Taking Adrenaline

Adrenaline is part of a class of medicines called alpha- and beta-adrenergic agonists (sympathomimetic agents) that work by relaxing airway muscles and tightening blood vessels.

Adrenaline can help:

  • Treat life-threatening allergic reactions from insects, medications, latex, foods, and other allergy triggers

  • Treat life-threatening hypotension (low blood pressure) from septic shock, a life-threatening immune response to infection

  • Restore cardiac rhythm during cardiac arrest (sudden loss of heart function) in people on advanced cardiovascular life support (ACLS)

  • Resuscitate newborn infants

  • Treat open-angle glaucoma, a chronic eye disease that damages the eye's optic nerve

  • Relieve symptoms of asthma, a lung condition that narrows the airways and makes it breathing difficult

How To Take Adrenaline

Adrenaline is available as a pre-filled injection that can be injected under the skin or into the muscle to treat life-threatening allergic reactions. It should be used at the first sign of a serious allergic reaction. Your healthcare provider can show you how to use and inject it.

Always use adrenaline exactly as directed, and do not inject more or less than prescribed by your provider. After you inject adrenaline, you will need to get emergency medical treatment.

In some cases, the injection will need to be injected intravenously (into a vein) by a healthcare provider.

Safety

Adrenaline should not be administered to people with high sensitivity to sympathomimetic drugs, which are used to treat conditions such as glaucoma and chronic obstructive pulmonary disease (COPD).

Before taking adrenaline, speak with your healthcare provider about your health conditions and the medications you take to avoid potential interactions. Adrenaline may interact with Benadryl (diphenhydramine) and Chlor-Trimeton (chlorpheniramine), which are antihistamines that relieve allergy and cold symptoms.

Exercise caution if you have ever had chest pain, hypertension, irregular heartbeat, heart disease, diabetes, hyperthyroidism (overactive thyroid), depression, asthma, or Parkinson's disease.

People who are pregnant, breastfeeding, or who plan to become pregnant should speak with their healthcare provider before taking adrenaline. There is not enough scientific evidence on the effects of adrenaline on pregnant humans, so adrenaline should only be used if the potential benefits outweigh the potential risks.

Side Effects of Adrenaline Medication

There are many potential side effects of adrenaline, which is why it is important to speak to your healthcare provider before taking it.

For example:

  • In people with hyperthyroidism, possible side effects include anxiety, headache, and heart palpitations.

  • Repeated injection of adrenaline can result in the narrowing of blood vessels, which can cause necrosis (death of body tissue).

  • Other side effects may include skin redness, difficulty breathing, weakness, dizziness, tremors, sweating, nausea, and vomiting.

  • Rare but severe side effects include intracerebral hemorrhage (brain tissue bleeding).



When To Seek Immediate Help

If you experience any side effects from adrenaline, see a healthcare provider or visit your nearest emergency room. If you accidentally injected too much, call the poison control helpline at 1-800-222-1222.



Other Ways to Increase Adrenaline

Studies show that adrenaline increases naturally through activities such as intense exercise, extreme sports, and watching scary movies.

These activities cause an adrenaline rush, which increases blood flow to the muscles and brain, relaxes muscles, and helps convert glycogen into glucose (sugar) in the liver.

A Quick Review

Adrenaline is a hormone and medication with a variety of functions and uses. It is released by the body's adrenal glands and triggers the sympathetic nervous system (SNS), which controls the body's natural fight-or-flight response to physical stressors and dangers.

People may take adrenaline as a medication to treat life-threatening allergic reactions or to treat low blood pressure from septic shock, among other health conditions.

There are many potential side effects of adrenaline, which include weakness, tremors, anxiety, and skin redness. Always speak to a healthcare provider before taking it. A provider can help monitor usage and address any possible side effects.

For more Health.com news, make sure to sign up for our newsletter!

Read the original article on Health.com.

Advertisement