Eli5: What is the body trying to do when it goes into anaphylactic shock?


Is it trying to fix itself by closing the airways?….Or is it just a reaction and not a defense.

In: 81

Anaphylactic shock is a severe allergic reaction that occurs when the body’s immune system overreacts to a foreign substance, such as a food, medication, or insect venom. The body’s immune system mistakes the substance for something harmful and releases chemicals to fight it off, which can cause a number of symptoms, such as difficulty breathing, a rapid heartbeat, and a drop in blood pressure.

In layman’s terms, the body is trying to protect itself from something it thinks is dangerous. But in the process of trying to protect itself, the immune system overreacts, causing a cascade of symptoms that can be life-threatening if not treated promptly.

During Anaphylaxis the immune system release Histamine, which causes the blood vessels to dilate, making the blood pressure to drop and cause the person to feel light headed and dizzy, And also constricts the airways making it difficult to breathe, This can happen rapidly and happen in multiple parts of the body simultaneously.

It’s a medical emergency and requires immediate attention, if you suspect someone is experiencing anaphylactic shock, call for emergency medical services or 911, and administer epinephrine if available.

Your body is trying to kill the intruder *at all costs*

Allergic reactions are your body seeing a benign(non-harmful) thing come in and hitting the panic button so it sends up alarms and gets the troops (immune system) to come fight it. One of the ways your body fights things is by releasing all sorts of cells that cause swelling.

Anaphylactic shock happens when your body panics and instead hits the “Nuclear launch detected!” button and release *all* the troops to go fight *everything* and just creates a huge amount of swelling which ends up blocking airways.

Allergies are incorrect triggers of the defensive systems to start with. Extreme allergic reactions come about when your immune system enters a battle to the death with something it can’t kill but it is a battle to the death soooo

-From the [Mayo Clinic](https://www.mayoclinic.org/diseases-conditions/anaphylaxis/symptoms-causes/syc-20351468)

> Causes
The immune system produces antibodies that defend against foreign substances. This is good when a foreign substance is harmful, such as certain bacteria or viruses. But some people’s immune systems overreact to substances that don’t normally cause an allergic reaction.

>Allergy symptoms aren’t usually life-threatening, but a severe allergic reaction can lead to anaphylaxis. Even if you or your child has had only a mild anaphylactic reaction in the past, there’s a risk of more severe anaphylaxis after another exposure to the allergy-causing substance.

>The most common anaphylaxis triggers in children are food allergies, such as to peanuts and tree nuts, fish, shellfish, wheat, soy, sesame and milk. Besides allergy to peanuts, nuts, fish, sesame and shellfish, anaphylaxis triggers in adults include:

>Certain medications, including antibiotics, aspirin and other pain relievers available without a prescription, and the intravenous (IV) contrast used in some imaging tests
Stings from bees, yellow jackets, wasps, hornets and fire ants
Although not common, some people develop anaphylaxis from aerobic exercise, such as jogging, or even less intense physical activity, such as walking. Eating certain foods before exercise or exercising when the weather is hot, cold or humid also have been linked to anaphylaxis in some people. Talk with your health care provider about precautions to take when exercising.

>If you don’t know what triggers an allergy attack, certain tests can help identify the allergen. In some cases, the cause of anaphylaxis is not identified (idiopathic anaphylaxis).

Hope that helps.

Tl;dr: (as I understand it)— more or less, some people’s physiological response to infection or venom intake; for lack of a better explanation: “over reacting” from a viewing perspective of how one persons body reacts as opposed to another— while the body feels it’s necessary, it can kill you.

Im definitely not a doctor. I’d probably read the article to fill in any gaps, but I sort of paraphrased it in the tl;dr.

Biological machines are not perfect. People act like Nature’s playing a video game and making decisions based on what will work best. In reality nature is just rolling dice and giggling at the outcome, with very little thought involved.

Anaphylaxis is a kind of allergic reaction. We still don’t understand a lot about allergies, but we know they’re a situation where the immune system goes too far. Imagine a fire crew shows up to a burning building and finds the fire is in just one room. They proceed to put the fire out, then walk through every room, spraying every wall with their firehoses so thoroughly the drywall comes apart. By the time they leave they’ve done more damage to the structure than the fire they came to fight.

That’s kind of what happens when an allergic reaction starts causing anaphylaxis. We think allergens are stuff the body identifies as bad that the immune system should attack. Sometimes that alone is one of nature’s little mistakes.

Across humanity, the average response to one of those triggers is not life-threatening. You might get sneezy, or a runny nose. That’s meant to expel airborne things. That happens by making tissues in certain places swell or activating certain glands. That’s why you also might get hives, or a wound where stuff got in gets sore. It’s part of and side effects of how your immune system deals with stuff, kind of like how the firefighters still damage a lot of stuff even when they’re careful.

But in a few rare people where nature’s experimenting, the tissue swells A LOT or the glands go into hyperdrive because the immune system isn’t like “get this out” but “HOLY SMOKES WE HAVE TO ELIMINATE THIS”. This system is already insane, so it doesn’t much care if it’s swelling your throat so much it blocks your airways, and the brain’s not set up to handle this kind of malfunction.

That’s also why the medicines we have in things like Epi pens work so well. They’re chemicals that tells the immune system “CHILL THE HECK OUT YO” very aggressively. This isn’t great either, and it tends to take a pretty big toll on a person’s body. But it saves their life, so it’s worth it. There’s just not a great way to dose it out so their immune system chills “a little”.

We’re still learning a lot about how this all works. One of the ways COVID kills people is very similar and we don’t know an awful lot about that either: it seems adept at teaching our immune system to fight our own body. Worse, we’re starting to learn some diseases can “erase” the “memory” our immune system has (this was discovered as a property of measles, and we’re suspicious COVID can do it too.)

So think about this pretty hard when people say “let nature take its course”. Sometimes “nature’s course” is to program someone’s body to kill itself if they pet a cat. To me that’s a pretty darn good reason to rebel against nature’s course at just about any opportunity we have.

Anaphylaxis is really dangerous, and probably the most lethal part about it is the amount of narrowing of airways that makes it near impossible to breathe. Inflammation specifically is designed to open up your blood stream to allow things like white blood cells and other types of cells to flow through and repair whatever is causing the problem. There is an issue here, though, in that there are blood vessels in your throat too.

Sometimes your body gets a little too confused and thinks opening up your blood vessels is more important than breathing itself, among other important functions in the body. It will inflame basically every blood vessel so that tons of anti-virus anti-bacterial junk can flow like crazy. So it does this to your throat’s blood vessels as well. Your throat inflames and bloats up so much that you can’t breathe. Blood will flow quite well, though. So really, your body is not trying to “kill” anything bad by closing your airways, it is more of a reaction.