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  • Which of these three people is doing something risky?

  • Is it the one who takes their cholesterol medication with grapefruit juice?

  • The one who takes Acetaminophen pain relievers

  • for a sore ankle before going out for drinks?

  • Or the one who's on a blood-thinning medication

  • and takes an aspirin for a headache?

  • Actually, all of them are.

  • Each has inadvertently created a drug interaction that could, in extreme cases,

  • lead to kidney failure; liver damage;

  • or internal bleeding.

  • Drug interactions happen

  • when the combination of a drug with another substance

  • causes different effects than either would individually.

  • Foods, herbal supplements, legal drugs, and illicit substances

  • can all cause drug interactions.

  • Most drug interactions fall into two categories.

  • Some take place when two substances' effects influence each other directly.

  • In other cases, once substance effects how the body processes another,

  • like how it is absorbed, metabolized, or transported around the body.

  • Blood thinners and aspirin, for example,

  • have similar effects that become dangerous when combined.

  • Both prevent blood clots from forming

  • blood thinners by preventing the formation of the clotting factors

  • that hold clots together,

  • and aspirin by preventing blood cells from clumping into groups

  • that become clots.

  • Individually, these effects are usually safe,

  • but taken together, they can prevent blood clotting to a dangerous extent,

  • possibly causing internal bleeding.

  • While blood thinners and aspirin are generally harmless

  • when taken individually,

  • interactions where one substance exacerbates the effects of another

  • can also take place between drugs that are independently harmful.

  • Cocaine and heroin are each dangerous,

  • and those dangers compound when the two drugs are combined

  • even though their behavioral effects may feel like they cancel each other out.

  • Cocaine is a stimulant, and many of its effects, like increased heart rate,

  • cause the body to need more oxygen.

  • But heroin, a depressant, slows breathing

  • reducing the body's oxygen supply just when it needs more.

  • This combination strains the organs and can cause respiratory failure and death.

  • The interaction between grapefruit juice and certain medications

  • in class of cholesterol-lowering drugs called statins,

  • has to do with drug metabolism.

  • The liver produces enzymes, molecules that facilitate the breakdown of substances

  • that enter the body.

  • Enzymes can both activate drugs,

  • by breaking them down into their therapeutic ingredients

  • from more complex molecules, and deactivate them,

  • by breaking harmful compounds down into harmless metabolites.

  • There are many, many different enzymes,

  • each of which has a binding site that fits a specific molecule.

  • Grapefruit binds to the same enzyme as statins,

  • making less of that enzyme available to break down statins.

  • So combining the two means that a greater concentration of the drug

  • stays in the bloodstream for a longer period of time,

  • potentially causing kidney failure.

  • Alcohol can also alter the function of the enzyme that breaks down Acetaminophen,

  • the active ingredient in pain relievers like Tylenol and paracetamol.

  • When someone takes Acetaminophen, some of it is converted into a toxic substance.

  • At the recommended dose,

  • there isn't usually enough of this toxic byproduct to cause harm.

  • But heavy drinking can alter enzyme activity

  • so more of that byproduct is produced,

  • potentially causing liver damage

  • even with what's usually a safe dose of acetominophen.

  • Meanwhile, the herbal remedy Saint John's Wort increases the liver's production

  • of a particular enzyme.

  • That means the drugs this enzyme is responsible for breaking down

  • get metabolized faster

  • sometimes too fast, before they can have their therapeutic effects.

  • In spite of the dizzying number of possible interactions,

  • most of the dangerous interactions with commonly used drugs are well known.

  • And new developments in science are helping us keep better track

  • of drug interactions than ever.

  • Some researchers are developing AI programs that can predict the side effects

  • of drug interactions before they occur,

  • using information about the landscape of protein interactions within your body.

  • For the new drugs that are being developed all the time,

  • supercomputers are being used to find potential interactions

  • while those drugs are still in development.

Which of these three people is doing something risky?

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B2 US TED-Ed drug enzyme aspirin blood liver

The dangers of mixing drugs

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    ktyvr258 posted on 2019/11/14
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