Serendip is an independent site partnering with faculty at multiple colleges and universities around the world. Happy exploring!

Can It Ever Be Too Much? The effects of epinephrine on the brain

Student Blogger's picture

Why seek to scale Mount Everest,
Queen of the Air,
Why strive to crown that cruel crest
And deathward dare?
Said Mallory of dauntless quest
`Because it's there.'

-Robert William Service

Inspired by George Mallory, a British mountaineer, Robert William Service’s poem, “Dauntless Quest”, poses a very interesting question (1). Why risk everything to climb one of the most dangerous mountains in the world for no tangible benefit? Or for that matter why risk losing your life for fifteen minutes of an adrenaline rush? For many years, extreme sports such as bungee jumping and skydiving, have appealed to many people despite the threat they pose to a person’s life. Personally, I have not partaken in many forms of extreme activity, but as strange as it sounds, I would very much like to satisfy my desire to jump thousands of feet out of a moving plane.

Epinephrine, also known as adrenaline, is a hormone released by the adrenal medulla through the sympathetic nervous system during an individual’s fight or flight response (2). If a person is in danger, the body’s endocrine system interacts with the nervous system to give the individual the ability to attack the threat or to take flight and run away. Epinephrine is a person’s natural boost of energy, and it is the hormone that gives college students the ability to write their ten page papers the night before the deadline, or for a mother to lift up a car in order to save her children. The secretion of epinephrine is controlled by the adrenal medulla, located near the abdomen, and the release is stimulated by a relative increase of either physical or mental stress. The hormone travels through the bloodstream and increases heart rate, blood sugar, and it increases an individual’s metabolic rate in order to produce the most amount of energy for the individual to utilize. As with other hormones, there is a normal level of epinephrine that is naturally in the brain and there are regulatory proteins that maintain a healthy balance. If the brain is under constant stress, more adrenaline is secreted through the adrenal medulla in order to satisfy the body’s needs. This is where the problem begins.

We live in an ever-changing and very fast paced society, where people must be constantly active and busy in order to keep up with the competition. Yes, there are energy drinks and pills that artificially provide the body with energy to get through the day, but adrenaline is the body’s all-natural energy boost. Living in a constant state of energy is not a healthy lifestyle because the brain is already continuously exposed to a plethora of stimuli, half of which are not consciously processed and by adding more stimuli for the brain to process the brain to fatigue much more quickly. An exhausted brain will not be much help when you are trying to perform trivial every day tasks. As with most addictions, the necessity to satiate a desire become overwhelming, and consumes the individual’s thoughts and actions. Adrenaline junkies are people who have a constant craving for the next high. The more times they achieve the adrenaline high, the more adrenaline they need to feel the same effect and the levels of adrenaline in their bloodstream eventually become very imbalanced. Adrenaline junkies mentally process everyday activities into emergencies in order to find ways to fulfill their quota of adrenaline. Without the constant secretion of the hormone in the bloodstream, an addicted individual can experience adrenaline withdrawal. Symptoms such as panic attacks, exhaustion, irritability, and restlessness are common to those who are incessantly on the move (3). Although there are no obvious physical symptoms, the mental symptoms that an individual experience are strong enough to alter moods and personalities.

Tests performed on rats have shown that an increased exposure to epinephrine increases the sensitivity of the sensory neurons (4). This means that when there are increased levels of epinephrine rats are more excitatory and capable of doing much more work. Although this experiment did not describe the after effects of the epinephrine exposure, I would predict that the rats would undergo a period of withdrawal because their hormones would need to return to their standard levels. Also, epinephrine injections are used to treat severe forms of allergic reactions (5). Commonly, the injections are administered incorrectly and the result is abnormally low blood pressure, which is a serious side effect to an overdose of epinephrine.

The consequences of persistent physical and mental stress prove to have negative effects on the body as the levels of epinephrine in the bloodstream become distorted. However, despite all the information that is available, people will still jump off the side of a bridge, in order to get that one-of-a-kind high. I have willingly sat in the third seat of a roller coaster that dropped 150-foot at 120 miles per hour, and I can say, it was one of the greatest experiences of my life.

Works Cited:

1); World of Worlds
2); The Definition of Epinephrine
3); Hurry Up and be Still: Freedom from Adrenaline Dependence
4); Epinephrine enhances the sensitivity of rat vagal chemosensitive neurons: role of B3-adrenorecpetor
5); Too much of a good thing, is it bad? Adrenaline on trial


Kakembo Fredrick 's picture

Is there a natural solution

If my body is secreting more adrenaline than needed,
do I have any alternative to bring back the hormone levels back to normal.
Without using drugs?

Joe's picture

Stress& copulation

back of my brain is in big pain,also my eyes hurt.Is this coused by too much adrenalin? Any sugestions will be appreciated!!!

Serendip Visitor's picture


what happens if you really overdose and you only see tunnel vision. does adrenaline encourage you to smack someone when they hit you????

Serendip Visitor's picture

natural levels of adrenaline

So my endocrinologist says I have above normal levels of adrenaline..He checked me out and all is well ;except for that....Does that make me more stresed than normal or is my level normal to me?

Sheree RN's picture

Possible Permanent Dammage

I'm curious to the permanent changes to brain activity & structure after chronic skydiving in excess of 5000 jumps.
There's an obvious gaze to the skydivers on the day of the activity; however, I've also noticed a flat affect
after a lapse of several weeks from their last jump with difficulty engaging in interpersonal situations. They're typically non-violent and peaceful while exhibiting an emotional detachment. There is definitely something irreversible occuring. An interesting study would involve brain scans at different experience levels in addition to at differing lapses between skydives.

Cosmin's picture

no adrenaline

hello! the "adrenaline junkie " pattern is bullshit.nobody is addicted to adrenaline.adrenaline is responsable for anxiety and panic.the euphoria which comes AFTER the risk(adrenaline) is due to dopamine.
the "big risk"(adrenaline) is needed for the reward mechanism(dopamine)to kick in.

Mustafa Şarkışla's picture

I want to ask something

I want to ask something (sorry about bad english)

is there any way to secrete adrenaline consciously? I mean secrete adrenaline without danger or that possible?I'm asking this question because i think i can do it!
When i do this,my heartbeats going 70 to 135/min.!also my eyes (pupilla?) is getting bigger even in a high lights.I'm starting to falt.And i cant do this unremitting..1 or 1,5 minutes at most.

Ben's picture

I personally, would love to

I personally, would love to fulfill about a hundred different adrenaline filled activities. The rush you get from it is just so immense that you can't help but love it and want to do it again.

When i was younger jumping off of the top diving board took me over an hour to eventually do, but once you've conquered the threats of risking your life (or swimming trunks) your reward is that natural high of adrenaline surging through your body making you feel invincible.

I found your article great to read and hope to hear more about this wonder drug - adrenaline. My question to you though is this. If epinephrine is naturally within every persons body (obviously) why do some seek more of it than others? would it be like a normal drug addiction, get some and want some more? it can't be because people can go to the same bungee jump or cliff dive and experience it totally differently. Personally, i'd be begging to go again whereas my mother would probably rather have a paintball gun shot at her. So why is it some people want this drug more than others despite the same exposure to it? Is this lust hereditary or a learnt thing?

If you do by any chance discover any of this please e-mail me and let me know, i'd be very excited to hear from you.

I have also been doing some research into Eagleman's time perception and believe epinephrine is the key to the better retaining of memories. Thank you

Evan's picture

It's genetics, not genetics, and both.

There are a couple of reasons.

One genetic precursor that leads people to an adrenaline filled lifestyle could be a dopamine deficiency. It's where activities that give 'normal' people a high degree of pleasure are severely diminished. Partaking in more difficult and adrenaline packed activities gives the feeling of reward and satisfaction that people intrinsically desire. Imagine that everything that constitutes a normal daily routine feels dull, boring, and unmotivating. That, you don't really feel 'alive' unless you're pushing the limits. Research into dopamine deficiency has been recently linked to 'addictive personality' traits, as well as manic depression. Ironically, it's a common personality trait shared by many people who achieve high degrees of success in life. For many who share this, adrenaline sports are just how we have fun and, in some cases it's a way for us to get a 'fix' when the other facets of life are dull/uninteresting. The ugly side of the coin is, it's much more difficult to stay motivated in non-challenging tasks and can possibly lead to severe depression. For people who live with this, it's not some magical ticket to success. It's more like a person who has a weakness and, as a result, achieves success (and probably overcompensates) through hard work and determination. In the wrong environment or under the wrong conditions it can lead to crippling depression and/or self-destructive behavior.

The non-genetic reason is a little different. Most people don't take the time to carefully consider how much of an impact hormones have on our life. Hormone levels are influenced by genetics but can vary greatly based on lifestyle. For instance, weight gain leads to a decrease in testosterone and increase in estrogen production. A lot of women who wonder why their husband's 'manly' qualities have diminished don't realize that the person they're with literally isn't as much of a man as he used to be. Multiple hormones that control mood and weigh gain are also balanced during sleep. Exercise and strenuous activities increase testosterone production. The more and the harder the difficulty, the more powerful and aggressive it makes you feel.

Recently, I read about a study where subjects were told to think about something that makes them angry whereby saliva samples were taken and measured and tested for testosterone. A similar study measured testosterone levels of guys who were asked to handle a gun. In both cases showed a marked increase in testosterone levels indicating a rise in aggression.

While testosterone is great for, drive, motivation, and generally just feeling great it's not healthy if that pent-up aggression is directed at other people. To participate in extreme sports at a high level, it takes more than just skill/technique. On a snowboard, cutting a fresh trail through an untouched forest or dropping into a 22ft half-pipe is something you don't want to spend too much time thinking about. It's a problem you have to dial in and literally attack. As opposed to the aggressive gym rats, cops, and wife beaters who invest most of that energy into posturing, intimidating, or literally attacking others; people who partake in extreme sports attack their inner fears and weaknesses. That's why you see competitive snowboarders will hug or give props to the each other after their sets. They're not competing against each other so much as bringing the highest degree of skill that they have been able to achieve in front of a live audience.

For people who have spent their whole life shying away from risk. Those years of unwavering focus to the boob tube, lack of sleep, caffeine dependency, addiction to stress, submissive social tendencies, acceptance of fear and weakness, are all literally and methodically killing your drive to accomplish great things.

Adrenaline junkies actively refuse to let it go and in some cases depend on it to find happiness.

Stacys's picture

This has helped me in so many

This has helped me in so many ways to understand what is wrong with me. Can you please elaborate on what can be done to treat this? I feel like I mainly have the genetic part, but also non genetic as well.

Mark's picture

Amen Evan! I have experienced

Amen Evan! I have experienced everything you mentioned.

Serendip Visitor's picture

primatene mist inhaler

primatene mist inhaler contains 0.33mg epinephrine.

I abuse these inhalers to treat my adhd.

Mount Everest's picture

Adrenaline on Mountains

Summit fever is all down to your own adrenaline. You may be totally worn out, but seeing the summit not to far away, adrenaline gives you that extra push you may or may not need.

Mount Everest The British Story