# All drugs are in our heads? **URL:** \ **Category:** Factual Questions\ **Created:** [April 6, 2010, 2:56pm UTC](https://boards.straightdope.com/t/all-drugs-are-in-our-heads/535147 "2010-04-06T14:56:14Z")\ **Posts on this page:** 20\ **Page:** 1
**Author:** ![gitfiddle](https://avatars.discourse-cdn.com/v4/letter/g/898d66/32.png) [@gitfiddle](https://boards.straightdope.com/u/gitfiddle)\ **Post date:** [April 6, 2010, 2:56pm UTC](https://boards.straightdope.com/t/all-drugs-are-in-our-heads/535147/1 "2010-04-06T14:56:14Z")
I know this might be a stupid question, but that, in part, is why I’m asking it. I was listening to this fascinating [Radiolab](http://www.wnyc.org/shows/radiolab/episodes/2007/05/18) podcast the other day, and one of the statements in there really caught my attention. Essentially the interviewee said that all of the drugs we make already exist in our heads/bodies. That’s the reason the pills we make work, because we have receptors that take in those chemicals. This seems to make a sense to me, but I’m not a doctor. So, is it true? ---
**Author:** ![Mijin](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/mijin/32/9369_2.png) [@Mijin](https://boards.straightdope.com/u/Mijin)\ **Post date:** [April 6, 2010, 3:10pm UTC](https://boards.straightdope.com/t/all-drugs-are-in-our-heads/535147/2 "2010-04-06T15:10:43Z")
The second part is true, not the first. Drugs work, generally, because we have receptors that take in those chemicals. (depending on how we define drug that “generally” may not be unnecessary). But it isn’t true that we already have caffeine, LSD, alcohol etc within our body, or that humans have evolved metabolic pathways specifically for these chemicals. ---
**Author:** ![Hirka\_T\_Bawa](https://avatars.discourse-cdn.com/v4/letter/h/db5fbb/32.png) [@Hirka\_T\_Bawa](https://boards.straightdope.com/u/Hirka_T_Bawa)\ **Post date:** [April 6, 2010, 3:16pm UTC](https://boards.straightdope.com/t/all-drugs-are-in-our-heads/535147/3 "2010-04-06T15:16:22Z")
Depends on the drug. There are many different compounds that act as a drug in the body. Most drugs need some sort of receptor in the body to actually do anything, however, that doesn’t mean that the substance actually exsists in the body itself. There are many drugs that are antagonists and block the action of an endogenous substance, or you have agonists that activate a receptor like the endogenous substance. You also have drugs that compete with binding sites with the substance in the body. So, drug molecules don’t normally exist already in the body, but they resemble in some way something the body responds to. ---
**Author:** ![purplehorseshoe](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/purplehorseshoe/32/2996_2.png) [@purplehorseshoe](https://boards.straightdope.com/u/purplehorseshoe)\ **Post date:** [April 6, 2010, 3:19pm UTC](https://boards.straightdope.com/t/all-drugs-are-in-our-heads/535147/4 "2010-04-06T15:19:22Z")
Wellllll … if you take in a substance, and your body does _not_ have receptors that bind with that substance, then generally, the substance will simply pass right through you without any noticeable effects. (The example I get off the top of my head is accidentally swallowing a loose tooth when you’re a kid. You don’t get high off it b/c there are no receptors that bind with enamel. Sorry, weird example, I know.) The podcast may have been referencing how people have, for example, cannabinoid receptors that very conveniently bind with cannabis. We don’t, however, already have THC floating around in our bloodstream naturally from birth or anything like that. But we don’t have redmapleoid receptors in our brains, so no one goes around smoking the leave of red maples. ---
**Author:** ![bizzwire](https://avatars.discourse-cdn.com/v4/letter/b/958977/32.png) [@bizzwire](https://boards.straightdope.com/u/bizzwire)\ **Post date:** [April 6, 2010, 3:23pm UTC](https://boards.straightdope.com/t/all-drugs-are-in-our-heads/535147/5 "2010-04-06T15:23:36Z")
All drugs do not exist within our bodies. You may have misunderstood what was said. Some drugs work by interacting with receptors and mimic naturally-occuring compounds the receptors were “designed” for. Other drugs interact with enzymes; they may be molecularly similar to the ligand the enzyme normally interacts with, but not necessarily. ---
**Author:** ![Hari\_Seldon](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/hari_seldon/32/5173_2.png) [@Hari\_Seldon](https://boards.straightdope.com/u/Hari_Seldon)\ **Post date:** [April 6, 2010, 3:40pm UTC](https://boards.straightdope.com/t/all-drugs-are-in-our-heads/535147/6 "2010-04-06T15:40:59Z")
Everyone who has responded seems to assume that the OP referred only to psychoactive drugs (which may indeed have been the intent–I gave up mind -reading decades ago). Penicillin, for example, reacts with receptors on bacterial cells, not human cells. ---
**Author:** ![Ludovic](https://avatars.discourse-cdn.com/v4/letter/l/7ab992/32.png) [@Ludovic](https://boards.straightdope.com/u/Ludovic)\ **Post date:** [April 6, 2010, 3:43pm UTC](https://boards.straightdope.com/t/all-drugs-are-in-our-heads/535147/7 "2010-04-06T15:43:46Z")
Radiolab is indeed fascinating, usually in the car-wreck sort of way. They’d find a better home at the Discovery Channel, a place much more forgiving of the woo they usually broadcast. ---
**Author:** ![Chronos](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/chronos/32/134_2.png) [@Chronos](https://boards.straightdope.com/u/Chronos)\ **Post date:** [April 6, 2010, 3:44pm UTC](https://boards.straightdope.com/t/all-drugs-are-in-our-heads/535147/8 "2010-04-06T15:44:17Z")
> [@](#): > > But we don’t have redmapleoid receptors in our brains, so no one goes around smoking the leave of red maples. So why is maple syrup so addictive? ---
**Author:** ![Quercus](https://avatars.discourse-cdn.com/v4/letter/q/7ab992/32.png) [@Quercus](https://boards.straightdope.com/u/Quercus)\ **Post date:** [April 6, 2010, 4:18pm UTC](https://boards.straightdope.com/t/all-drugs-are-in-our-heads/535147/9 "2010-04-06T16:18:23Z")
…and to be picky, even the ‘receptors’ part isn’t always true. For instance, the dizzying effect of alcohol isn’t caused by any receptors that are sensitive to alcohol. It’s a purely physical effect of adding alcohol to the water-based inner ear fluid causing changes to the density, etc, of the fluid, which makes it move differently than the body is calibrated for. ---
**Author:** ![ralph124c](https://avatars.discourse-cdn.com/v4/letter/r/8797f3/32.png) [@ralph124c](https://boards.straightdope.com/u/ralph124c)\ **Post date:** [April 6, 2010, 4:22pm UTC](https://boards.straightdope.com/t/all-drugs-are-in-our-heads/535147/10 "2010-04-06T16:22:05Z")
Excuse me, but why haven’t we moved away from drugs…to actual electrical stimulation of the brain? This would be the solution for drug addiction-you could “dial in” the amount of stimulation you wanted, and dispense with dangerous and addictive drugs. ---
**Author:** ![Ludovic](https://avatars.discourse-cdn.com/v4/letter/l/7ab992/32.png) [@Ludovic](https://boards.straightdope.com/u/Ludovic)\ **Post date:** [April 6, 2010, 4:28pm UTC](https://boards.straightdope.com/t/all-drugs-are-in-our-heads/535147/11 "2010-04-06T16:28:22Z")
> [@ralph124c](#): > > Excuse me, but why haven’t we moved away from drugs..to actual electrical stimulation of the brain? This would be the solution for drug addiction-you could “dial in” the amount of stimulation you wanted, and dispense with dangerous and addictive drugs. Because AFAIK right now the only way to do that is to drill holes in the skull. Otherwise you can’t directly stimulate the right parts of the brain. But I agree that more research should be done to move toward direct brain stimulation. ---
**Author:** ![Qadgop\_the\_Mercotan](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/qadgop_the_mercotan/32/83_2.png) [@Qadgop\_the\_Mercotan](https://boards.straightdope.com/u/Qadgop_the_Mercotan)\ **Post date:** [April 6, 2010, 4:34pm UTC](https://boards.straightdope.com/t/all-drugs-are-in-our-heads/535147/12 "2010-04-06T16:34:34Z")
> [@Quercus](#): > > For instance, the dizzying effect of alcohol isn’t caused by any receptors that are sensitive to alcohol. It’s a purely physical effect of adding alcohol to the water-based inner ear fluid causing changes to the density, etc, of the fluid, which makes it move differently than the body is calibrated for. Cite for this? I had believed it was due to interference at multiple levels of the cognitive and the proprioceptive locations within the brain, rather than just futzing with the labyrinthine system. But I’m certainly interested if it’s been demonstrated to be all in the inner ear. ---
**Author:** ![Qadgop\_the\_Mercotan](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/qadgop_the_mercotan/32/83_2.png) [@Qadgop\_the\_Mercotan](https://boards.straightdope.com/u/Qadgop_the_Mercotan)\ **Post date:** [April 6, 2010, 4:36pm UTC](https://boards.straightdope.com/t/all-drugs-are-in-our-heads/535147/13 "2010-04-06T16:36:47Z")
> [@ralph124c](#): > > Excuse me, but why haven’t we moved away from drugs..to actual electrical stimulation of the brain? This would be the solution for drug addiction-you could “dial in” the amount of stimulation you wanted, and dispense with dangerous and addictive drugs. What’s more elegant? Adding tailored molecules which only act on selected receptors in certain parts of the brain/body to stimulate them, or placing a wire into a general region and disrupting the electrical conduction of everything it touches? ---
**Author:** ![Quercus](https://avatars.discourse-cdn.com/v4/letter/q/7ab992/32.png) [@Quercus](https://boards.straightdope.com/u/Quercus)\ **Post date:** [April 6, 2010, 5:40pm UTC](https://boards.straightdope.com/t/all-drugs-are-in-our-heads/535147/14 "2010-04-06T17:40:25Z")
> [@Qadgop\_the\_Mercotan](#): > > Cite for this? I had believed it was due to interference at multiple levels of the cognitive and the proprioceptive locations within the brain, rather than just futzing with the labyrinthine system. > > But I’m certainly interested if it’s been demonstrated to be all in the inner ear. Well, it’s possible that, like Rick in Casablanca, I was misinformed. If so, I expect to be swiftly corrected by your firm and loving hand, uh, tentacle. Quick search, which is all I have time for now, couldn’t find anything more authoritative than wiki: [Vestibular system - Wikipedia](http://en.wikipedia.org/wiki/Vestibular_system#Pathologies), which seems to say there is indeed a role played by alcohol concentrations affecting the physical properties of inner ear fluid (though that article can’t seem to decide whether it’s viscosity or density that’s at issue). I certainly am not trying to say that all balance and coordination effects of alcohol are due to inner ear issues. If current thinking is that there is no contribution from the inner ear, then I eagerly await the tentacle of correction. But if there is any contribution from the inner ear (regardless of what other pathways contribute to balance issues), then the original point stands: which is that alcohol has an effect through a pathway that doesn’t involve alcohol receptors. ---
**Author:** ![Kobal2](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/kobal2/32/20_2.png) [@Kobal2](https://boards.straightdope.com/u/Kobal2)\ **Post date:** [April 6, 2010, 6:27pm UTC](https://boards.straightdope.com/t/all-drugs-are-in-our-heads/535147/15 "2010-04-06T18:27:33Z")
> [@Qadgop\_the\_Mercotan](#): > > What’s more elegant? Adding tailored molecules which only act on selected receptors in certain parts of the brain/body to stimulate them, or placing a wire into a general region and disrupting the electrical conduction of everything it touches? Plugging steel bolts wired to 5V batteries straight into one’s brainpan does have that steampunk, orky aesthetic going for it :). ---
**Author:** ![Qadgop\_the\_Mercotan](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/qadgop_the_mercotan/32/83_2.png) [@Qadgop\_the\_Mercotan](https://boards.straightdope.com/u/Qadgop_the_Mercotan)\ **Post date:** [April 6, 2010, 7:20pm UTC](https://boards.straightdope.com/t/all-drugs-are-in-our-heads/535147/16 "2010-04-06T19:20:53Z")
> [@Quercus](#): > > Well, it’s possible that, like Rick in Casablanca, I was misinformed. If so, I expect to be swiftly corrected by your firm and loving hand, uh, tentacle. Snout. Xmex-like snout. After consulting my sources, I find that you are indeed correct that it’s been the longstanding model that infiltration of alcohol into the endolymph of the labyrinth contributes to the vertigo of acute alcohol intoxication. My literature reviews have shown that the chronic balance disturbances associated with prolonged alcohol use are the ones that involve more central portions of the brain. Often these two phenomena combine, for one great trip! ---
**Author:** ![Qadgop\_the\_Mercotan](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/qadgop_the_mercotan/32/83_2.png) [@Qadgop\_the\_Mercotan](https://boards.straightdope.com/u/Qadgop_the_Mercotan)\ **Post date:** [April 6, 2010, 7:23pm UTC](https://boards.straightdope.com/t/all-drugs-are-in-our-heads/535147/17 "2010-04-06T19:23:01Z")
> [@Kobal2](#): > > Plugging steel bolts wired to 5V batteries straight into one’s brainpan does have that steampunk, orky aesthetic going for it :). Which is fine if one is just trying to re-animate dead tissue or do operant conditioning for yes/no-type behavior. But it lacks _panache_ (in my opinion.) Plant subtle ideas and alter behavior in myriad ways with designer molecules flitting around from frontal lobes to limbic system to the hypothalamus, that’s the ticket! ---
**Author:** ![Chronos](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/chronos/32/134_2.png) [@Chronos](https://boards.straightdope.com/u/Chronos)\ **Post date:** [April 6, 2010, 7:35pm UTC](https://boards.straightdope.com/t/all-drugs-are-in-our-heads/535147/18 "2010-04-06T19:35:28Z")
> [@](#): > > Snout. Xmex-like snout. And polydactyl tongue. ---
**Author:** ![Smeghead](https://avatars.discourse-cdn.com/v4/letter/s/f1d935/32.png) [@Smeghead](https://boards.straightdope.com/u/Smeghead)\ **Post date:** [April 6, 2010, 7:43pm UTC](https://boards.straightdope.com/t/all-drugs-are-in-our-heads/535147/19 "2010-04-06T19:43:04Z")
> [@Qadgop\_the\_Mercotan](#): > > Which is fine if one is just trying to re-animate dead tissue or do operant conditioning for yes/no-type behavior. > > But it lacks _panache_ (in my opinion.) Plant subtle ideas and alter behavior in myriad ways with designer molecules flitting around from frontal lobes to limbic system to the hypothalamus, that’s the ticket! Collaboration time! Do you want to write the grant proposal, or shall I? ---
**Author:** ![Qadgop\_the\_Mercotan](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/qadgop_the_mercotan/32/83_2.png) [@Qadgop\_the\_Mercotan](https://boards.straightdope.com/u/Qadgop_the_Mercotan)\ **Post date:** [April 6, 2010, 7:45pm UTC](https://boards.straightdope.com/t/all-drugs-are-in-our-heads/535147/20 "2010-04-06T19:45:06Z")
> [@Chronos](#): > > And polydactyl tongue. _Xymolosely_ polydactyl tongue. And that’s for special. [Next page](https://boards.straightdope.com/t/all-drugs-are-in-our-heads/535147.md?page=2)