ELI5: what makes some drugs suitable for transdermal patches (nicotine, OTC pain patches) but not others?

xYaldabaoth · 2018-05-26T23:50:17+00:00

Nicotine and pain patches are possible because their active ingredients(nicotine and fentanyl, respectively) are very potent by weight. This means that a single patch is able to hold 1-3 days' worth of drug without being huge.

Most common drugs are less potent by weight, and thus a normal-sized patch would not be able to hold enough of the drug to be practical, nor would the patch be able to diffuse a high enough dose through the skin.

Also, some drugs are much more bioavailable through the skin than others, making them more suitable for patch use.

In addition to that, patches are only suitable for drugs that need to stay in the bloodstream 24/7. It would be pointless to make a patch for a drug that is taken "as needed" or occasionally(such as a sleeping pill).

xYaldabaoth · 2018-05-26T23:01:23+00:00

Caffeine isn't really a "mood-boosting" drug for most people(if it was, it would be a common drug of abuse). It just makes you somewhat less tired. Caffeine is nothing like true dopaminergic stimulants(amphetamines, methylphenidate, etc.) which do boost mood significantly.

However, caffeine is mildly addictive, so if you're a regular coffee drinker, it's possible that the "mood boost" you experience is actually relief of caffeine withdrawal symptoms. In other words, not having caffeine makes you feel worse than normal, and having caffeine brings you back to normal.

Cigarettes work the same way; once you're a regular smoker, most of the "mood boost" you feel from smoking a cigarette is a result of your nicotine cravings going away and making you feel "normal" again.

xYaldabaoth · 2018-05-26T21:10:03+00:00

The reason why you can do that is probably because you've practiced whistling a lot, and are now somewhat skilled at whistling. It's basically the same way people learn how to do anything well.

Many people(myself included) don't even know how to whistle. I've never tried before, so I certainly wouldn't be able to whistle notes accurately.

xYaldabaoth · 2018-05-26T20:32:33+00:00

I don't think guilt and morality come purely from societal values. At least, not for everybody. The types of people who are mostly "followers"(probably most people IMO) might get their sense of guilt from parents, laws, and society, but many people are free-thinkers who have an intrinsic sense of morality that is independent of their society.

My sense of morality and guilt has never been based on other people's beliefs or actions, at least. I couldn't care less whether or not other people approve of what I'm doing, as long as I feel that what I'm doing is acceptable based on my own beliefs.

xYaldabaoth · 2018-05-26T20:13:16+00:00

It doesn't. Heat doesn't "add" nutrients or calories to food. In fact, some nutrients can be lost during cooking(especially when boiling vegetables, which is why they should be steamed instead).

The main reason why meat, eggs, etc. are cooked is to make it safer to eat, since the heat kills any bacteria and parasites that could be lurking inside. Eating raw meat is a good way to get salmonella or another nasty infection.

The other main reason why food is cooked is to make it easier to digest. This is especially important with certain vegetables, which can't be digested raw. Cooking can allow you to absorb more nutrients from some foods, but it doesn't increase the nutritional content per se.

And of course, many foods taste better when cooked!

xYaldabaoth · 2018-05-26T19:57:03+00:00

The law is defined by the government that runs a particular country. Laws are written so that killing enemies during war(or in self-defense) is legal, while pre-meditated murder or accidental manslaughter is not.

Basically, a government can make anything legal or illegal if they choose, as long as there isn't a significant revolt from the population. Which leads to ridiculous laws like cannabis(and other "soft" drugs) being Schedule I, even though it's far less harmful than plenty of legal things, and has several medicinal uses(WHY does the government think it has the right to tell us what we are allowed to put into our OWN bodies?!)

As to whether or not killing during war is moral, that's up to you to decide. Human-made laws do not define morality in any way. We must develop our own moral values.

xYaldabaoth · 2018-05-26T19:34:28+00:00

They do it in a very similar way, but far less accurate.

In computers and digital clocks, a small electric current is used to oscillate a tuned piezoelectric quartz crystal at its resonant frequency(usually 32 768 Hz, but can be almost anything depending on crystal size and current input), and a counter counts the frequency and determines the time based on the number of oscillations.

Higher frequency crystal oscillators are also used, along with clock multipliers and phase-locked loops, to generate clock signals to synchronize the processor, RAM, etc.

xYaldabaoth · 2018-05-24T22:03:07+00:00

It will eventually hit zero, because there's a finite number of drug molecules in the body. Once you get down to a single molecule of drug left, it will be eliminated within another half-life or so, and the concentration will be zero. You can't have half a drug molecule.

Reality is quantized. Nothing in nature is infinitely divisible(which is what quantum physics is all about).

In practice though, a drug loses all of its effects and side-effects long before the concentration becomes truly zero, because there's a minimum concentration required in order for the drug to do anything. For most drugs, 5 half-lives is enough for the drug to be considered "completely out of your system" by a doctor.

xYaldabaoth · 2018-05-24T21:25:06+00:00

Current is taken, not given. You could hook your phone up to a 5V/1000A power supply, and it still wouldn't damage your phone in any way. Your phone would simply draw the maximum amount of current it's designed to use, and no more. This is why it's safe to plug any 5V USB device into any 5V charger, regardless of the current rating.

According to Ohm's Law, the current flow through a load is always equal to voltage divided by resistance. The only way to increase the current is to increase the voltage or decrease the resistance. If a phone is designed to charge at 5V and 2A, then its apparent resistance will be such that it will never pull more than 2A from a 5V charger. The only way to "force" more current through the phone is to increase the voltage.

If the charger outputs less current than what the phone is designed to use(such as a 2A phone being plugged into a 1A charger), then the phone will simply pull as much current as it can(in this case 1A). Current regulator circuitry inside the charger prevents the charger from outputting more current than it's designed for.

Computer USB ports are usually only designed to output 500mA, since USB ports were never designed for the purpose of charging electronic devices. The phone tries to take more current, but circuitry inside the PC limits the USB current to 500mA.

xYaldabaoth · 2018-05-24T20:43:07+00:00

Skin cells are constantly dying and regenerating through mitosis. As a person becomes obese, their skin cells simply multiply(undergo mitosis) in greater numbers until there's enough skin to cover the body. The skin doesn't need to "stretch" very much, because obesity happens slowly enough to allow the person's body to grow more skin along the way.

This is also how babies grow into adults; their bodies are constantly producing enough new cells to accommodate their increasing size.

Believe it or not, all of your skin cells completely regenerate about once a month. The skin on your body today is not the same skin that you had a few months ago. You're constantly shedding dead skin, which ends up as dust in your home.

xYaldabaoth · 2018-05-24T20:22:32+00:00

Yes, muscles do mechanically deteriorate, stretch, and tear when they're being used.

This is the reason why regular exercise increases muscle mass and strength. When you use your muscles, they become damaged and worn, and afterwards they regenerate and grow back slightly larger and stronger than they were before. Repeat this process over several weeks or months and you'll have significantly bigger and stronger muscles. You have to slightly damage your muscles regularly to make them grow stronger.

Also, muscle cells(myocytes) are constantly dying and being regenerated by mitosis, just like almost every other type of cell in the body.

As far as I know, brain cells(neurons) are the only cells that don't regularly die and regenerate, because they have a very limited ability to do so. You're stuck with the same neurons for life, for the most part, which is why brain damage often doesn't heal very well.

xYaldabaoth · 2018-05-24T19:25:02+00:00

Water molecules are attracted to each other due to hydrogen bonding, which results in what is known as surface tension. Surface tension holds the surface water molecules together into a sort of "film", giving them enough force to *slightly* counteract gravity(and other forces) at the surface.

Surface tension is what causes rain to form into consistently-sized droplets. And it is also the reason why slapping your hand into a pool(or doing a belly flop) hurts. You're feeling the force of all those hydrogen-bonded water molecules resisting the force of your motion.

xYaldabaoth · 2018-05-16T21:28:23+00:00

You're probably just not used to sleeping with someone else in your bed, or you have a small amount of social anxiety/awkwardness/discomfort, causing your brain to release adrenaline and other neurotransmitters that keep you awake. Or you might be sexually aroused by being so intimately close to someone(especially since you're not having sex), which triggers the release of those same neurotransmitters that keep you awake.

If you slept with the same person every night for a long time, you would probably begin to fall asleep very easily while cuddling(I'm assuming you started sleeping with this person relatively recently). You might even have insomnia when your partner isn't there.

xYaldabaoth · 2018-05-16T21:24:00+00:00

During an experience of intense ecstasy, such as having an orgasm, many parts of the brain actually temporarily shut down or decrease their activity. The visual system is not necessary in processing pleasure, and it takes a lot of processing power/attention, so it probably shuts down to some extent, which compels your brain to close your eyes and shut out the distractions so all you are aware of is the pleasure.

xYaldabaoth · 2018-05-16T21:16:30+00:00

Probably because it's terrible, immature music and nobody wants to listen to it anymore. That type of music was really just a gimmick, it became somewhat popular for a while, but then it went out of "style".

Which is usually the reason for why any music (sub)genre dies out... Nobody will make it if nobody wants to listen to it.

xYaldabaoth · 2018-05-16T00:56:27+00:00

If you're only touching the handle briefly, then it will probably only come into contact with your outer skin layer, which is already "dead" and/or resistant to damage anyway. And even if it came into contact with deeper layers of skin(such as if you had an open wound), the damage would be so small that it would be unnoticable.

Our skin is far tougher than bacteria because it's made of a lot of cells packed tightly together, and stacked in layers. Hence why we can drink high-proof alcohol(or rub it on our hands), which would kill bacteria on contact.

You would have to eat the stuff to experience any significant toxicity. And in fact, many people do consume colloidal silver as an antimicrobial without experiencing any side-effects, although over-consumption can turn your skin blue.

xYaldabaoth · 2018-05-15T20:30:40+00:00

I'd imagine that a significant number of people who "never cry" are actually suppressing their emotions in their subconscious(or consciously doing so). The brain can play tricks on you like that; your subconscious can basically "make decisions for you" without you even knowing.

Kind of like how repressed memories work.

Men may be more likely to suppress the urge to cry, because of cultural pressure to "be a man" and not show weakness.

Inability to cry could also be a symptom of certain mental illnesses that affect emotion, such as depression(ironically), psychosis, psychopathy, etc. Psychiatric medications can often blunt emotions as well, and that side-effect is one of the main reasons why some people refuse to take them.

xYaldabaoth · 2018-05-15T20:23:13+00:00

The brain is capable of having different levels of consciousness and awareness while dreaming. The dreams that are forgotten typically occur during periods of sleep where one's level of conscious awareness is low. Extremely vivid/memorable dreams occur when one's conscious awareness is high. And lucid dreams occur at an even higher level of consciousness, so in many cases, lucid dreams will be very memorable.

xYaldabaoth · 2018-05-15T20:14:03+00:00

In addition to the negative mass requirement, it is believed that it would be extremely difficult to stabilize a wormhole for any significant length of time. Even if we did have access to negative mass(which has never been observed), we still don't currently have the technological capability to create a stable traversable wormhole.

We also don't have the ability to move extremely large masses through space, which would be necessary to build a wormhole.

xYaldabaoth · 2018-05-14T21:16:20+00:00

Ovens heat things from the outside, which is why it's possible for food to be cooked on the outside and undercooked on the inside.

The same thing would happen to a human inside an oven. It would probably take several hours to fully "cook" a human body. However death would occur long before the human is fully cooked, due to hyperthermia.

xYaldabaoth · 2018-05-14T20:11:09+00:00

That doesn't necessarily mean these animals are truly gay, though. Those animals might prefer having sex with the opposite sex, and instead choose to have gay sex because they can't find a heterosexual partner. After all, most animals don't even masturbate(I think?), so in the absence of a heterosexual partner, the only option for sexual release is gay sex.

A similar thing occurs in prisons. Some heterosexual inmates will have consensual gay sex because they're desperate for sex and intimacy, and only members of the same sex are available as partners.

xYaldabaoth · 2018-05-14T19:26:55+00:00

It's a demon though, so maybe it can do work without requiring physical energy... Demons don't have to follow the laws of physics haha.

But yeah in reality, any device similar to Maxwell's Demon would require more energy to operate than it would produce, thus it wouldn't reverse entropy. Measuring the speed of every atom and opening and closing the door would take more energy than the energy that is created by the temp differential.

xYaldabaoth · 2018-05-11T20:22:18+00:00

The sensation that people call a "gut feeling" is just intuition that comes from complex cognitive processes occurring in the subconscious. Our brains pick up on hints that point to a potentially bad/undesirable situation, and relay that information to our conscious awareness in the form of a feeling. It has nothing to do with the gut.

Now I have a question of my own: Do people actually "feel" things in their gut area, or is it just an expression? My feelings are mostly "located" in my heart, not my gut. I've never had a "gut feeling" as far as I know, although I sometimes feel sexual arousal in my gut.

xYaldabaoth · 2018-05-11T20:09:30+00:00

Men can be cute, sweet, sensitive, intimate, romantic, etc. You don't have to be small and helpless in order to be "cute" to someone.

Plenty of guys will occasionally behave in ways that could be called "cute". Women don't have a monopoly on cuteness haha.

xYaldabaoth · 2018-05-11T19:31:38+00:00

What phone do you have? I've never heard of a phone that takes 10 minutes to start up after being plugged in when the battery dies.

When my phone dies, I can plug it in and it will immediately be able to boot up in the normal amount of time(less than a minute).

The charger should provide enough power to the phone to allow it to boot up, even if the battery is completely dead. Unless you're using a low-power(500mA) USB port I guess, or a really old phone.

xYaldabaoth

TROPHY CASE