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  #1  
Old 08-18-2010, 08:43 PM
ChrisBooth12 ChrisBooth12 is offline
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Quickest way for a substance to be absorbed in the body.

What is the quickest medium to inject chemicals into a person and have them react to it? Say medications for example. I think the quickest way would be an IV, but than I thought that snorting a medication would be a faster way than IV or syringe, even though medications are not made to be used in that fashion. A pill would have to be the slowest form, or second slowest if you count skin contact. I know not all medicines are not made the same but is their any reason why any medication could not be made in pill, powder and liquid form or even combustible? ignoring meds with time released affects of course.

Note: This is in no way referring to illegal drug use.
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  #2  
Old 08-18-2010, 08:48 PM
Joey P Joey P is offline
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From what I've heard. Snorting is the fastest because the sinuses are so close to the brain. But I think it's going to depend on what you're trying to accomplish.

I can say that when I inject Imitrex (IM) I can feel it working within seconds. Things that I've snorted, depending on what they are, usually take longer then that.

Last edited by Joey P; 08-18-2010 at 08:50 PM..
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  #3  
Old 08-18-2010, 09:39 PM
GiantRat GiantRat is offline
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Since the goal is (usually) to get the substance into the bloodstream, I have to think that IV would be fastest.

I've heard that lingual (specifically sub-lingual) administration is next best. Although IANAAD (I Am Not An Acid Dropper).

Now that I thunk on it, in regard to heroin a major cause of death is idiot kids sniffing heroin, then deciding that it's not good enough any more, and deciding to "mainline" for a stronger high. That would support the IV approach in terms of rapid delivery.
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  #4  
Old 08-18-2010, 10:14 PM
DSeid DSeid is offline
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It depends a bit on what the target organ is, but generally the answer is inhalation. The goal is not to get it to the bloodstream but to whatever is the target organ.

Inhalation gets to organs like the brain quickest and that is part of why cigarettes are so addictive. The reason is a simple mechanical one. Place something into the venous circulation and it has to make its way to the right side of heart, get pumped through the lungs, return to the other side of the heart, and then get pumped to the end target, such as the brain. Inhale it and it is absorbed into the pulmonary venous circulation and goes from there to the left side of the heart and to the end organs, shortcutting half the trip.

Of course you could do better by injecting into an artery that feeds the target organ but that is hard to set up outside of a hospital intensivist setting.

And if the target is the liver then injecting into a vein that goes through the liver on its way to the heart would get it there the fastest.

If the reaction aimed for is a systemic allergic reaction then injection wins I think as you'd fairly immediately come into contact with the histamine releasing eosinophils.

But for most target organs, including brain, inhalation wins.

Snorting and injection are both going venous, snorting getting absorbed into nasal capillaries first, so indeed snorting is a bit slower, but I think the bigger issue is that there is a limit to how much that surface can effectively absorb in a certain time period, whereas an injection can allow whatever dose someone wants to kill themselves with.
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  #5  
Old 08-19-2010, 07:04 AM
Harmonious Discord Harmonious Discord is offline
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The quickest way for chemicals to get into your body is through direct skin absorption. Not all compounds work quickly this way, but you didn't specify a certain compound.
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  #6  
Old 08-19-2010, 07:51 AM
Yllaria Yllaria is offline
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PICC lines put the chemical right on the heart's front door. It's not something you can do yourself, though.
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  #7  
Old 08-19-2010, 04:01 PM
Canadjun Canadjun is offline
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Quote:
Originally Posted by Yllaria View Post
PICC lines put the chemical right on the heart's front door. It's not something you can do yourself, though.
Seems to me that it would be somewhat faster than injecting into a vein, but whatever went into the PICC line would still need to go from the heart to the lungs, back to the heart, and then out to the rest of the body. So, if you want to affect the brain, then as DSeid said, inhalation would probably still be faster.
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  #8  
Old 08-19-2010, 08:38 PM
mnemosyne mnemosyne is offline
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Quote:
Originally Posted by ChrisBooth12 View Post
...I know not all medicines are not made the same but is their any reason why any medication could not be made in pill, powder and liquid form or even combustible? ignoring meds with time released affects of course.
There are lots of reasons why a drug cannot be delivered in just any form desired, most of which I know that I'm not even aware of because I've never worked in formulation development.

A drug that is stable in a tablet form with X, Y and Z as an excipient might not be very stable when placed in water for an injection - the usual medium for injectables (if your drug hydrolyses before you even take it, you have a problem). Some drugs are sensitive to light, so a powder delivery system where it might be exposed (e.g. snorting) might cause it to degrade while a tablet coating will prevent that from happening. A powdered drug might absorb water from the air too, also causing degradation problems.

Combustion is likely to destroy a lot of organic molecules as they react with oxygen in a hot environment. Taking a tablet might not work if the drug degrades significantly when exposed to stomach acid, or even to saliva, or perhaps is unstable once it gets to more neutral and slightly basic environments in the GI tract, thereby necessitating IV or other administration form.

Since cells differ by tissue type, it's possible that the cellular uptake mechanism applicable to the drug is less active in the GI than it is in the circulatory system (this is a WAG, but a somewhat educated one!)

Offhand, I'd say that there are a couple of year's worth of development for any given drug just to figure out how to get it into the patient's bloodstream without it degrading or killing the patient.

As the VP of my department used to say, "Chemistry happens, and it's a bitch". Stuff will react/degrade/misbehave no matter how much you think you know when you start studying it!
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  #9  
Old 08-20-2010, 02:00 AM
t-bonham@scc.net t-bonham@scc.net is offline
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So how do suppositories compare to pills in terms of speed?
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  #10  
Old 08-20-2010, 02:29 AM
Mosier Mosier is offline
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Quote:
Originally Posted by t-bonham@scc.net View Post
So how do suppositories compare to pills in terms of speed?
The answer is "it depends". There are a bunch of medications which are meant to be swallowed that don't work well as suppositories, and plenty of medications which would not do well in the stomach environment that are meant to be suppositories.

Generally, if something is meant to be digested, it takes longer to see an effect from the medication than typical medications using other routes. There are some medications which take a very very long time to absorb through the skin and would actually kill you through overdose if you tried to ingest them, though. Like I said, it depends.

Generally, medications which need to get into the blood stream take longer to see an effect if they are digested, and are faster if they are injected into a vein. Inhalation is even faster for some medications, but there are also some medications which can be either injected or inhaled, with the inhalation route requiring much stronger dosages and taking much longer to see the same effect as you would through the IV route. Paramedics who have to administer emergency cardiac medications through a breathing tube are working with a patient in very serious trouble, and they will only use that route if absolutely no other routes are available.

There is no "right" answer here, except to say that stuff you want in the blood stream typically works faster through IV if it is in liquid form. Inhalation typically works faster if the drug you want to administer can be vaporized.
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  #11  
Old 08-20-2010, 08:05 AM
The Great Philosopher The Great Philosopher is offline
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I thought it was to stab a needle directly into the heart, Pulp Fiction-style. Cecil covers it, and he seems to imply that intracardiac injection is one of the quickest delivery methods, but has so many problems and is so dangerous that it's almost never used in practice.
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