Here’s What Happens to Your Body During Anaphylaxis

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According to the Centers for Disease Control and Prevention, allergies affect more than 50 million Americans every year—and anaphylaxis, the most severe allergic reaction, affects at least 1.6 percent of the general population [PDF]. Here’s the science of what happens to the body during anaphylactic shock.

ALLERGEN EXPOSURE

In a person with allergies, cells sometimes identify foreign but innocuous stimuli as major threats. Why some people are allergic to certain things while others are not is a mystery science hasn't yet solved, but we do know how it happens: through a process called sensitization.

Here’s how it works. When the body encounters a foreign substance, also called an antigen, immune system cells deliver some of substance's molecules to T-helper cells living in the lymph nodes. Those cells also bring along a type of molecule that informs a T-helper cell it’s time to stage an immune response. Known as a costimulatory molecule, it's necessary to activate any type of immune system reaction involving T cells, whether you have allergies or not.

Being exposed to an antigen "primes" a T-helper cell, turning it into a Th2 cell. Primed Th2 cells release proteins called interleukins, which do two things: First, they interact with another type of immune cell called B cells to produce infection-fighting antibodies that bind to mast cells, which contain chemical particles they'll release in the presence of an antigen. Second, the interleukins activate eosinophils, a type of white blood cell that discharges toxic substances to destroy invading cells (and, occasionally, host cells). In this process, the immune system identifies the "threat" and deploys cells prepared to fight it. The immune system's elevated level of awareness of and preparation against the antigen reclassifies the substance as an allergen—a considerably more dangerous threat.

Because an allergy only develops after this process, a person allergic to strawberries, for example, will only experience a reaction the next time they eat something containing strawberries. New allergies can pop up at any point in your life.

An immune system on allergies is a little bit like a brain that can't distinguish a piece of lint from a spider: unable to relax, constantly on guard against every potential threat. After initial exposure, the mast cells activated during the sensitization phase are still equipped with allergen-specific antibodies and remain combat-ready, prepared to respond immediately should a second exposure ever occur. If it does—and it probably will—here’s what you can expect to happen.

ALLERGIC REACTION

If two or more allergen molecules bind to a sensitized mast cell, the mast cell releases inflammatory mediators that produce an allergic reaction. These mediators include substances like histamine and more of the interleukins that, in turn, activate eosinophils, Th2 cells, and basophils (another type of white blood cell). In a non-allergic reaction, mediators produce helpful inflammation that prevents infection and initiates healing—but those same symptoms can be annoying and even dangerous when the immune system attacks an otherwise benign allergen. Mast cells also release leukotrienes, which recruit more immune cells to the area and speed up the reaction. That leads to what Stanford University researcher Tina Sindher calls a “‘chain reaction’ of allergic inflammation.”

With the release of histamine, you might experience both bronchial contraction—which makes it more difficult to breathe—and blood vessel dilation. The latter makes it easier for blood to flow to affected areas, but it also makes blood vessels more permeable, allowing blood to escape from the blood vessel walls and flow into the spaces between cells and causing swelling and hives.

For most, these symptoms are merely uncomfortable; they can occur as late as eight to 12 hours after initial exposure, long after the allergen is gone, and can be alleviated with an antihistamine like Benadryl. But for a person with severe allergies, a life-threatening allergic response can occur within minutes: Their airways will constrict so much they won't be able to breathe, and their blood vessels will be unable to contract, which can lead to a drop in a blood pressure and keep veins from getting blood back to the heart. The combination of airway constriction and blood vessel dilation can make it impossible for the body to supply enough oxygen to major organs—that's anaphylactic shock.

The only way to stop anaphylaxis in its tracks is with epinephrine, more commonly known as adrenaline. Adrenaline is a hormone naturally produced by the adrenal glands to help generate the "fight or flight" response in emergency situations. It works by constricting certain blood vessels, increasing blood pressure, and relaxing airways, counteracting all the reactions produced by histamines.

According to Sindher, it’s important to use epinephrine immediately if you're at risk for anaphylactic shock. “There’s a general belief out there that epinephrine should only be used in the worst-case scenario,” she tells Mental Floss. “In fact, most of the complications we see in food allergic reactions are due to delayed use in Epi. Antihistamines can be helpful in treating the symptoms of itching and congestion, but they do not help stop an allergic reaction.”

THE FUTURE OF ALLERGY TREATMENT

Researchers like Sindher are still trying to understand what causes allergies, and why the prevalence of food allergies has increased over the past few decades. Sindher’s main goal is to find new ways of treating (and hopefully curing) allergies. The most established technique (for food allergies, at least) is oral immunotherapy, where allergic individuals gradually eat more of their allergen until they can have small amounts without experiencing a reaction. That’s usually done extremely gradually, over the course of months or years, and always under the supervision of a certified allergist.

image of two epipens sitting on a desk
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Sindher says scientists are still testing other types of immunotherapy treatments and vaccinations in clinical trials: “A lot of research is going into trying to identify the causes so we can be successful in the prevention as well as treatment of food allergies.”

Until that happens, though, doctors say the best course of action is to be careful around allergens. Medications are useful and necessary, but prevention is the name of the game when it comes to allergies.

Debunking 6 Common Home Remedies That Aren't Worth Trying

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While it’s never fun—or cheap—to go to the doctor, sometimes you just have to bite the bullet and make an appointment. While you may read a slew of articles online during your middle-of-the-night WebMD binge, the “natural” home remedies that some blogs swear by are often at best no better than placebos, and at worst actively harmful.

A new video from SciShow explores several home “remedies” that don’t actually help treat common medical issues. The nine-minute video debunks some of the "natural" treatments that people often cite as cures for ailments as benign as allergies or as serious as poisoning. Spoiler: Most of them have no scientific basis.

If, for instance, you’ve ever heard the idea that local honey can act as an allergy cure, put down the spoon. Despite being delicious, honey doesn’t provide enough exposure to the allergens that cause those sniffles and itches to help. When your seasonal allergies hit, take medication or visit an allergist instead.

How about the old custom of putting butter on a burn? Unsurprisingly, fatty foodstuffs don’t make great wound treatments. While people used to believe that burns shouldn’t be exposed to air, oily substances like butter will actually trap heat from your burn, making it worse. The key to treating a burn is cooling it off. You want to stick it in cool water, not warm butter.

If you are unlucky enough to catch head lice, you're probably willing to try whatever you can get your hands on to destroy the little critters. But that pricey medicated shampoo really is the best way to go. Scientists have found that washing your hair with vinegar isn’t the answer. Researchers have found that lice nesting in hair aren’t affected by vinegar, even when the hair in question is soaked for 8 hours.

Some of these home remedies seem a little out-there, but others are understandable. Ipecac syrup once had a place on every pharmacy shelf as a method of treating people who ingested poison. The syrup is poisonous itself, and it makes you vomit—but vomiting isn’t a guarantee that your body has rid itself of all the toxins, and it might just make it harder for your doctor to diagnose what’s going on. Poison Control no longer recommends keeping ipecac syrup on hand, and U.S. manufacturers stopped making it in 2010.

Tilting your head back to staunch a nosebleed is yet another common treatment that can backfire on you. Tilting your head back does stop the blood from flowing from your nose. But it means that your blood will flow down your throat instead of out your nose. So instead of getting a towel bloody, you put yourself at risk of choking on your own blood.

The last “remedy” SciShow tackles isn’t directly harmful, but it won’t help, either. Some people recommend treating pink eye by using warm chamomile tea bags as eye compresses. While chamomile does have some anti-inflammatory properties, there’s no evidence that chamomile is at all effective in treating pink eye. Draping warm tea bags over your eyes probably won’t harm you, and in fact, the heat may relieve some pain, but the tea itself isn’t going to cure you.

Dive into the facts behind these “remedies” in the video below. And remember: when in doubt, always go to the doctor.

[h/t Digg]

The U.S. State With the Most Psychopaths Is …

Anthony Perkins stars in Psycho (1960)
Anthony Perkins stars in Psycho (1960)
Paramount Pictures

Quaint, quiet Connecticut—home of the Frisbee and the first speed-limit law—is also apparently home to the most Norman Bates types. A recent study spotted by Quartz ranked each U.S. state by the number of psychopaths who are estimated to be living there, and the results may surprise you.

Following Connecticut, the top five states by psychopathy are California, New Jersey, New York, and Wyoming (New York and Wyoming tied). The least psychopathic state, on the other hand, is wild and wonderful West Virginia.

Psychopathy on its own is not a clinical diagnosis. Rather, it's a subset of antisocial personality disorder, whose symptoms include egocentrism, manipulativeness, impulsivity, lack of remorse, and an inability to form intimate relationships, just to name a few.

The study, posted on the Social Science Research Network (SSRN), partly drew data from previous research on the “big five” personality traits—Extroversion, Agreeableness, Conscientiousness, Neuroticism, and Openness to Experience—and their prevalence in each state [PDF]. Ryan Murphy, the study's author, said there's a correlation between these personality traits and some of the traits associated with psychopathy—namely boldness, meanness, and disinhibition.

“Boldness corresponds to low neuroticism and high extraversion, meanness corresponds to low agreeableness, and disinhibition corresponds to low conscientiousness,” Murphy told Quartz. In the earlier study of personality scores by state, Connecticut showed high levels of extraversion and comparatively low levels of conscientiousness.

The District of Columbia was also taken into consideration and showed higher levels of psychopathy than any state in the country. However, Murphy said this isn’t a fair representation because D.C. is an urban area and cannot be accurately compared to a larger, more geographically diverse region.

Although D.C. was excluded from the final ranking, Murphy said there might be something to the popular belief that politicians are more likely to be psychopaths: “The presence of psychopaths in [the] District of Columbia is consistent with the conjecture found in [my research] that psychopaths are likely to be effective in the political sphere.”

It must be noted, though, that these findings have only recently been pre-published and are not yet peer-reviewed.

Here’s how the 48 contiguous states (excluding Hawaii and Alaska) ranked for psychopathy:

1. Connecticut
2. California
3. New Jersey
4. & 5. New York / Wyoming (tied)
6. Maine
7. Wisconsin
8. Nevada
9. Illinois
10. Virginia
11. Maryland
12. South Dakota
13. Delaware
14. Massachusetts
15. Arizona
16. Florida
17. Iowa
18. Colorado
19. Texas
20. Ohio
21. Utah
22. Arkansas
23. Idaho
24. North Dakota
25. Michigan
26. Alabama
27. Pennsylvania
28. Rhode Island
29. Louisiana
30. Kansas
31. Georgia
32. Minnesota
33. Missouri
34. Washington
35. Kentucky
36. Nebraska
37. South Carolina
38. New Hampshire
39. Oregon
40. Indiana
41. Mississippi
42. Montana
43. Oklahoma
44. New Mexico
45. North Carolina
46. Tennessee
47. Vermont
48. West Virginia

[h/t Quartz]

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