Speaker 1: Welcome to Brainstuff, a production of iHeartRadio. Hey brain Stuff,
Speaker 1: Lauren Bogelbaum. Here, we all experience some aches and pains
Speaker 1: as we move through the world in are weird and
Speaker 1: wonderful human bodies. Sometimes we take something to ease that pain,
Speaker 1: and on a global level, that something is most often
Speaker 1: aspirin or pacetylsalicylic acid. About forty thousand metric tons of
Speaker 1: aspirin is produced and consumed every year. That's over one
Speaker 1: hundred billion tablets. It's not only used for headaches. It
Speaker 1: can ease fevers and inflammation too, and millions of people
Speaker 1: take aspirin to help prevent heart attacks. There are good
Speaker 1: reasons a doctor might say, take to aspirin and call
Speaker 1: me in the morning. So today let's talk about how
Speaker 1: aspirin works and how it doesn't, and how some good
Speaker 1: science helped it become the most common drug in the world.
Speaker 1: As far back as three thousand BCE or thereabouts, ancient
Speaker 1: Mesopotamian physicians were writing about the use of parts of
Speaker 1: the willow tree to treat pain and inflammation. The ancient Chinese, Egyptians, Greeks,
Speaker 1: and Romans all recorded their use of willow extracts but
Speaker 1: it wasn't until the eighteen hundreds ce after the birth
Speaker 1: of the field of chemistry, that we started to understand
Speaker 1: why willow can work for these purposes. In the eighteen twenties,
Speaker 1: a few different chemical detectives, including Friedrich Buchner and Henri LaRue,
Speaker 1: isolated an extract of willow that was very bitter and
Speaker 1: very potent for use in treatment of things like rheumatism.
Speaker 1: They called it salasin, after a Latin word for willows salix.
Speaker 1: Over the next couple of decades, other chemists figured out
Speaker 1: the molecular structure of salacin and how it can be
Speaker 1: oxidized to produce the related compound salcilic acid, and then
Speaker 1: how to synthesize salasilic acid at a large scale in labs.
Speaker 1: In the eighteen seventies, due to this discovery, the Hayden
Speaker 1: Chemical Company in Germany became the first ever industrial manufacturer
Speaker 1: of any drug, and the commercial market for salasylic acid
Speaker 1: boomed for use in treating pain and swelling in diseases
Speaker 1: like arthritis and fever. In illnesses like the flu. The
Speaker 1: problem with salasilic acid is that it can upset the
Speaker 1: user's stomach fairly badly and even cause bleeding in the
Speaker 1: digestive tract at high doses, but researchers were working on
Speaker 1: it enter one of Hayden's national rivals, Bayer in Company.
Speaker 1: In the eighteen nineties. Chemists at Beayer reasoned that perhaps
Speaker 1: salicilic acid was so hard on the stomach because it's
Speaker 1: an acid. They knew from research back in the eighteen
Speaker 1: fifties in France that you can use chemical reactions to
Speaker 1: cover up one of the acidic parts of seala silic
Speaker 1: acid with an acetyl group, converting it to acetyl salicilic acid.
Speaker 1: They figured out how to synthesize pure medical grade aceetyl
Speaker 1: salicilic acid, and after a couple of years of testing,
Speaker 1: Beyar patented this effective and easier on the stomach medication
Speaker 1: under the trade name aspirin in eighteen ninety nine. They
Speaker 1: got the name by combining a for a setyl with
Speaker 1: a word derived from spyriea, which is the genus name
Speaker 1: for metal sweets, which are other plants that you can
Speaker 1: get salasin from. Today, the name aspirin has been role
Speaker 1: generic in a number of countries. There's actually a bit
Speaker 1: of a debate now about who at Bayer was responsible
Speaker 1: for synthesizing this compound. For decades, corporate lore said it
Speaker 1: was a junior chemist by the name of Felix Hoffmann,
Speaker 1: whose father had arthritis, so he was motivated to help
Speaker 1: ease his side effects from taking salicilic acid. But one
Speaker 1: hundred years after aspirn came out, at the turn of
Speaker 1: the twenty first century, credible evidence arose that Hoffmann's boss,
Speaker 1: one Arthur Eisngrun, was more responsible, but because Eisngrune was Jewish,
Speaker 1: his involvement was downplayed. With the rise of the Nazi regime,
Speaker 1: It's a mystery of history. Another long running mystery that
Speaker 1: has since been solved is how aspirin works in the body.
Speaker 1: We didn't know for sure until the nineteen seventies, when
Speaker 1: a team of pharmacologists and biochemists came up with proof,
Speaker 1: for which they were rewarded the Nobel Prize in Medicine
Speaker 1: in nineteen eighty two. It took humanity all of these
Speaker 1: millennia to figure it out, partially because pain is complicated
Speaker 1: like no one is totally sure how it works, and
Speaker 1: the more we learn, the more questions seem to arise. Okay,
Speaker 1: like all other sensory experiences. Pain exists only because your
Speaker 1: brain says it does, your body's way of telling you
Speaker 1: that something has gone wrong that needs your attention. Let's say,
Speaker 1: for example, that you hit your thumb with the hammer
Speaker 1: instead of the nail you're aiming for. Please don't try
Speaker 1: this at home. Now. Your thumb has nerve endings in it.
Speaker 1: These are little detectors in your joints and skin that
Speaker 1: feel things like heat, vibration, and everything from featherlight touch
Speaker 1: to the big crushing shock of being hit with the hammer.
Speaker 1: There are different receptors for each of these types of sensations. Also,
Speaker 1: when you hit your thumb and damage that tissue, nearby
Speaker 1: cells will release some chemicals that make your nerve endings
Speaker 1: register the crushing shock more strongly, like turning up the volume.
Speaker 1: Some of those chemicals are ones called prostaglandins. So very basically,
Speaker 1: you smash your thumb and the nerve endings involved send
Speaker 1: now strong signals up through your nervous system and into
Speaker 1: your brain, which which decides that these signals mean hey,
Speaker 1: that hurts. The pain you experience is useful information because
Speaker 1: it tells you that your thumb is damaged and that
Speaker 1: you should put the hammer down and be careful with
Speaker 1: the thumb until it's healed. Prostaglandins contribute only a portion
Speaker 1: of the total pain signal, but it's an important portion,
Speaker 1: and prostaglandins also help cause the site of the injury
Speaker 1: to swell up. This bathes the injured tissue in blood
Speaker 1: and helps rush immune system resources into protect it and
Speaker 1: start the healing process. Basically, it's a good system, but
Speaker 1: a few problems can arise. First Off, pain is not
Speaker 1: a neutral feeling. It's emotionally upsetting, so once you've registered
Speaker 1: your bodily damage, having that pain signal continue isn't fun
Speaker 1: or even particularly useful. Secondly, something's hurt without there being
Speaker 1: a hammer or or open flame, or some other source
Speaker 1: of damage that you can avoid. You might get a
Speaker 1: headache because your scalp and neck muscles are contracted from stress,
Speaker 1: or because a blood vessel in your brain has a spasm. Thirdly,
Speaker 1: as we've talked about before on the show, autoimmune conditions
Speaker 1: like arthritis or psoriasis can cause your immune system to
Speaker 1: turn on healthy tissue, causing too much inflammation, which itself
Speaker 1: can be painful and even damaging. These processes appear to
Speaker 1: involve prostaglandins as well. Aspirin helps with these problems by
Speaker 1: stopping your tissue from releasing prostaglandins by preventing your cells
Speaker 1: from making them. Okay, cells working in damaged tissues produce
Speaker 1: prostaglandins using an enzyme called cyclooxygenase two, or COX two.
Speaker 1: COX two can be found and lots of normal tissues,
Speaker 1: but much more of it is made in tissue that's
Speaker 1: been hurt in some way. Aspirin, as it turns out,
Speaker 1: sticks to COX two and won't let it do its job.
Speaker 1: It's like sticking gum in a lock instead of a key.
Speaker 1: Don't try this at home either, take my word for it.
Speaker 1: The lock will not open with gum in it, and
Speaker 1: COX two can't work with aspirin stuck in it. So
Speaker 1: by taking aspirin you don't stop the problem that's causing
Speaker 1: the pain, like the tight muscles in your scalp or
Speaker 1: the hammer damaged finger. But it does lower the volume
Speaker 1: on the pain signals going through your nerves to your
Speaker 1: brain and will prevent some inflammation from happening. This is
Speaker 1: not a targeted therapy. Aspirin doesn't know where to go
Speaker 1: in your body. When you take a tablet, it dissolves
Speaker 1: in your stomach or small intestine, and your body absorbs
Speaker 1: it from there into your bloodstream, which carries it through
Speaker 1: your entire body. Although it circulates pretty much everywhere, it
Speaker 1: only works where there are prostaglandins being made, including the
Speaker 1: area where it hurts. But the solution is not permanent.
Speaker 1: As with almost all chemicals, your body has a way
Speaker 1: of getting rid of aspirin. In this case, your liver, stomach,
Speaker 1: and other organs convert aspirin to salicylic acid. Your liver
Speaker 1: then sticks other chemicals onto the salisilic acid so that
Speaker 1: your kidneys can filter it out of your blood and
Speaker 1: send it out through your urine. The whole process takes
Speaker 1: about four to six hours, so you have to take
Speaker 1: another pill at that time if you want to keep
Speaker 1: the effect going. This is also a good but imperfect system.
Speaker 1: There are places in your body that need prostaglandins for
Speaker 1: various reasons. For example, in your stomach, a related enzyme
Speaker 1: COX one makes a prostaglandin that seems to keep your
Speaker 1: stomach lining nice and thick. Aspirin prevents that too, meaning
Speaker 1: that taking aspirin over time can cause your stomach lining
Speaker 1: to get thin, allowing your digestive juices to irritate it.
Speaker 1: This is probably the biggest reason why aspirin upsets stomachs,
Speaker 1: not only because it's an acid, as Bayer's chemists thought.
Speaker 1: There are other places in the body where prostaglandins have
Speaker 1: a job. In normal tissues, such as the blood. Some
Speaker 1: types of prostaglandins cause tiny particles in your blood known
Speaker 1: as platelets, to stick together in forming blood clots. By
Speaker 1: inhibiting prostaglandin production, aspirin slows down clot production. This can
Speaker 1: be bad, like if you have a bloody nose or
Speaker 1: a cut, in which cases you absolutely want a clot
Speaker 1: to form, so maybe avoid taking aspirin there. But blood
Speaker 1: clots can hurt us, as can happen in heart attacks
Speaker 1: when clots clog the blood vessels that carry oxygen through
Speaker 1: your hard working heart. That's why aspirin is recommended by
Speaker 1: healthcare providers to some people looking to prevent a heart
Speaker 1: attack or to recover from one. The way that aspirin
Speaker 1: lowers fevers also has something to do with its inhibition
Speaker 1: of prostaglandins, this time in the hypothalamus, which is a
Speaker 1: part of the brain that helps control body temperature, among
Speaker 1: other things. This one might be more complicated, though research
Speaker 1: is ongoing. But okayke anything you can take in. There
Speaker 1: is such thing as too much aspirin, and it can
Speaker 1: cause some unwonted side effects like bleeding or bruising if
Speaker 1: it prevents blood clots and upset or damage to the stomach.
Speaker 1: A risk of these side effects increases when you take
Speaker 1: aspirin alongside some other drugs like other painkillers, plus blood thinners,
Speaker 1: and many antidepressants. Additionally, aspirin is not recommended for bringing
Speaker 1: down the fever of kids with virus infections like the
Speaker 1: flu or chicken pox, because aspirin is associated with a
Speaker 1: deadly condition called rhye syndrome. In cases like those, drome
Speaker 1: causes brain damage, so aspirin should not be given to
Speaker 1: children and less directed by a healthcare provider for a
Speaker 1: specific condition. But for these reasons, scientists have found other
Speaker 1: chemicals related to aspirin that have some of its good
Speaker 1: effects and lack some of its bad ones. For example, abuprofin,
Speaker 1: sold under the brand names advil or motrin, and nepoxin
Speaker 1: or a leave can also treat pain, swelling and fever,
Speaker 1: but seem to have less of effect on platelets than
Speaker 1: aspirin does. All three of these are in a class
Speaker 1: called non steroidal antiinflammatory drugs because they decrease swelling, but
Speaker 1: they're not steroids, which are the most potent antiin inflammatories
Speaker 1: that we have. A Different class of medicines related to
Speaker 1: aspirin includes acetaminifin or tailanol, which decreases fevers and pain
Speaker 1: but doesn't affect inflammation or your stomach as much as
Speaker 1: nonsteroidal anti inflammatories do, and all of these options are
Speaker 1: generally safer for kids. Even with different options, asprin is
Speaker 1: still something of a wonder drug today. More research is
Speaker 1: being done to see if it might be able to
Speaker 1: help with other conditions, like some forms of cancer. As always,
Speaker 1: human bodies are complicated, so talk to a healthcare provider
Speaker 1: if you have any questions. But the next time you
Speaker 1: get out a hammer, think of those thousands of years
Speaker 1: of willow use and maybe set aside an aspirin or two.
Speaker 1: It's best to be prepared just in case you hit
Speaker 1: the wrong nail. Today's episode is based on the article
Speaker 1: asprin one oh one on HowStuffWorks dot com, written by
Speaker 1: doctor Lucas Hoffman. Brain Stuff is a production of iHeartRadio
Speaker 1: in partnership with HowStuffWorks dot com, and it's produced by
Speaker 1: Tyler Playing. For more podcasts from my heart Radio, visit
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Speaker 1: your favorite shows.