Ask The Owlet

I'll be finishing my second year of med school and hopefully will have passed the 300 hours of basic immunology in my curriculum.

 

That does depend on the painkiller in question.

Before we get to that: 'why does it just affect pain'. for one, your body has specific nerves for detecting pain, called nociceptor. Other stuff, like say, temperature or pressure are detected via *other* nerves, which is why it's possible to only loose specific sensations. For example, my dad suffered a traumatic (in the medical sense) arm injury as a kid, resulting in him having had basically no temperature reception in his arm downwards from the injury, but retaining his 'feeling' (he can accurately judge grip strength, for example) otherwise. There are different nocisensors for different damages: 'sharp', 'heat/chemical' and 'silent' ones which do only get activated in response to inflammation reactions in the tissue. This will be relevant in a bit.
Nociceptors are specifically for 'the thing we are receiving rn is likely to cause damage, and therefore ought to avoided'

Now that we got that out of the way: How Do Painkillers Kill Pain?

Well, several ways, depending on the kind of painkiller.

They are usually classed depending on what sort of chemical they are, but you can also split into 'localized' and 'generalized', and how they work. We're gonna focus on the 'how' rn.

The probably most well known analgesics (med. speak for painkiller) are opioids.
Most of them (not all can pass the blood brain barrier) work basically in your brain, by attaching your your opioid receptors in there (normally your body uses those for its endorphines). Depending on which specific opioid you're looking at, they can inhibit or activate those receptors and basically stop your brain from perceiving that fact that you're hurting. The nociceptor keep firing but the brain doesn't recieve the signal anymore (or not in full strength), thus making the pain 'less'.

Then there's the class of analgesics that you're probably most personally familiar with: NSAIDs.
This group includes aspirin, ibuprofen and naproxen. They mostly work by suppressing certain phases of inflammation responses in the body. As mentioned above, there are nociceptors that specifically come online when the tissue around it experiences inflammation, so suppressing the inflammation means these nociceptors don't get active and therefore can't smack your brain with the 'hello I'm hurt' signal. Depending on which NSAID you use, they may also delay blood clotting (aspirin esp does so irreversibly, which is why you can use the liquid form to treat blood clots sometimes), though they may also relax the smooth musculature (which is why some are more effective to treat period cramps than others) or interact with the body's endocannabinoid system - which is not completely understood but also looks to be involved in pain reception and transduction. NSAIDs seem to mostly do their thing by inhibiting the COX1 and COX2 enzymes, which are again involved in pain reception and inflammation responses. It should be noted that the exact mechanisms of action of NSAIDs have not been entirely cleared up yet.

Another popular over the counter analgesic is Paracetamol.
It works similarily to NSAIDS, but unlikely them, only has rather limited anti-inflammatory action in the body (which is why it's not commonly counted among NSAIDs) but does do something very similar in the brain by blocking COX2 in there.

Now for some of the less classical ones: Alcohol and Cannabinoids

Alcohol is a fairly general central nervous system depressor, meaning it depresses activity in the brain, which can include making pain reception less acute. Due to alcohol's negative side effects, it's not a great idea to do that, but people have been known to selfmedicate with it for a reason.

Cannabinoids do interact with the endocannabinoid system, naturally. Since as mentioned above, this system seems to play into pain reception, cannabinoids do accordingly have the potential to interact with it in a way that reduces pain.

Some pain medications are used topically. The mechanism is action here is usually the same one as when taken internally (there are gels containing NSAIDS for example) but due to being applied from the outside, the active ingredient is only introduced into the tissue, not he blood stream, so it doesn't work systemwide.

I hope this was helful!

 

Related question: I've been morphine'd in the ER twice. Once was when I had appendicitis, and the other was for one of my random bouts of excruciating back pain. Same drug, same person, similar levels of pain, but the effect was totally different: when I had appendicitis, it still hurt just as much after the morphine but felt like it hurt a little farther away and I was a little loopy and less stressed out, but the back pain just instantaneously and completely vanished. Were the appendicitis doctors just really stingy with the dose? I vaguely assumed at the time that the back pain might be a really severe muscle cramp and the morphine made the muscle relax, but, well, that's not how it works.

 

This is a bit of a gross question, but it’s something I’ve always wondered: why is it that sometimes when you pee, your piss is super warm (hot even), and sometimes it’s not as warm? Is it something about minuscule fluctuations in body temperature or something?

 

I sometimes have that feeling even if I haven’t been cold (it’s usually a morning thing for me?), but that’s definitely a thought!

 

*giggles like a middle schooler* you said cocks

 

do some people's joints make more noise than others? people have always been extremely alarmed about my loud neck cracking/spine popping but it's just the way i've always sounded

 

What two cents I can offer on the pee conundrum: circadian rhythm does include natural fluctuations in body temperature. Generally you should be warmer in the morning and your body temperature should drop a little at night as you become drowsy. Morning and night here are relative to your own sleep cycle. Maybe if you are actually waking early in the day when the surrounding temperature tends to be relatively cool, and your body temperature is headed up towards the morning peak, that could combine to create that effect? But I dunno.

 

Yes. The noise is small bubbles bursting in the liquid that surrounds your joints. The exact formation of those bubbles isn't quite clear yet, but some people seem to be more prone to generating them than others.

 

Got a weird one for you: why do I get dizzy when pulling magnets apart? Like anything stronger than an average fridge magnet, when pulled off something it's stuck to within about a foot of me, will make me nauseated. No one else I've ever met has experienced this. Am I am alien or an I just unusually sensitive to some Perfectly Normal Thing other people don't notice?

 

I once had to put my head down on my desk in class because the teacher was talking about the anatomy of the spine. I was close enough to fainting that my vision was beginning to go. Nobody else seemed remotely distressed.

So I haven't heard of anyone else who has that response to magnets specifically, but I have been a person who has such a response when no one else does. I don't know if everyone experiences this, but I wouldn't think it was so uncommon it would mark you as an alien.

ETA: I totally thought this was a different thread, so probably not the actual medical explanation you were expecting, but oh well?

 

Yeah I'm coming up empty. Humans are not really thought it have the ability to sense magnets. There's a cryptochrome in our retinas that theoretically could but it's light sensitive and could thus only work with eyes open and we don't even know if it actually performs a magnetoceptic functions in us. Experiments to far have been fairly inconclusive - that is, studies have been done that hint at it, but every time someone else tried to replicate those studies, they came up empty.

 

So either an alien or a mutant. Neat.

 

That one i can potentially explain: depending on individual anatomy, it's possible that you either reduce blood flow to your brain (by pinching a vein a little), or alternatively, pinched a nerve that did the same thing. If it's one of those, it's possible that growing a little since then has straightened the issue out so it wouldn't happen anymore. Alternatively, does it still happen? Because if so, examining under his circumstances it hits you could provide a hint to where the faulty vein is sitting.

 

No, it hasn't happened in years. It only happened when I was already upset about the spine to the point of unbearable distress including physical symptoms such as nausea, which sounds potentially relevant? I dunno, spines are freaky. My anxiety was very much less treated at the time. (Edit: I just realized I was also probably like, maybe 22 at the time?)

I did sometimes have momentary loss of vision while standing suddenly as a teen that cleared up as an adult. I don't think there's anything different that has never been recreated in my adult life except maybe untreated low thyroid that might explain that, but I think growth is probably more likely. It seemed like a fairly common teenage problem. It wasn't disabling. I could easily continue walking based on the memory of what I'd seen as I stood, and it cleared up fast enough that that was never likely to be insufficient.

 

why do my joints (specifically my neck and shoulders) hurt when i drink alcohol? (it seems worst with wine for some reason.) i've seen things saying "heavy drinking can exacerbate existing inflammatory conditions and cause pain later"-- but i don't have any (diagnosed) inflammatory conditions, it happens right away, and doesn't require heavy drinking. i had less than half a glass of wine the other day, and my shoulders immediately started hurting. it goes away after maybe 20 or 30 minutes, but it's weird. does this mean i have arthritis or something? if it goes away so fast, am i doing any damage if i have a glass of wine once in a while?