When you read about the mechanism of action, or how it works, in Zyprexa’s PI sheet, it’s almost as vague as how likely it will work. Pretty much every beginning paragraph of the mechanism of action section for every crazy med (and many other non-crazy meds) is a variation on “We don’t know exactly how Panacea, or other drugs like it, works to treat whatever you take it for. In various studies, mostly on rats and other animals, we’ve determined that it does the following…”
After researchers who aren’t being paid by the manufacturer get their hands on med it’s just one study after another, in humans and animals, that supports the original theory. Or determines a precise area in the brain where stuff takes place. Or finds an additional thing the med does. Or finds that it doesn’t do something they originally thought it did. Or finds out that everyone was completely wrong in the first place and the method of action is radically different. That last one does happen. Neurontin (gabapentin) was originally thought to be a synthetic form of GABA that could cross the blood-brain barrier. Turns out that it’s just like every other anticonvulsant and works on voltage channels. Except that it’s unique in that it affects a part of your brain that nothing else touches. Except for Lyrica (pregablin), and a few meds under development (e.g. PD-210714). Still, some people are calling those parts of your brain some people are calling those “gabapentin receptors”, along the lines of benzodiazepine receptors. There supposedly were citalopram receptors as well, but that turned out to be a myth. Ironically gabapentin doesn’t directly affect GABA.
Every day a new peer-reviewed journal is published somewhere adding to our knowledge about how a particular med works, or making us crazier with more contradictory data.
It would be nice if we could break things down into neat parameters like we can with pharmacokinetics, but we can’t. The best we can do is tell you what they originally thought it did, let you know if there are any meds with similar mechanisms / methods (the terms are interchangeable) of action1, and give you our best guess as to what it really does based upon more recent research.
§1. How Zyprexa (olanzapine) Works
the originally theorized mechanism of action
§2. Drugs with Similar Methods of Action as/That Work Like Zyprexa (olanzapine)
§3. What Zyprexa (olanzapine) Really Does
as far as we can tell
Based on the chemical imbalance theory of schizophrenia and bipolar disorder (and brain cooties in general) Zyprexa works by being a broad-spectrum atypical antipsychotic that impedes the transmission of serotonin, norepinephrine, and dopamine at a bunch of receptors. It is also a potent anticholinergic (which helps to prevent antipsychotic-induced movement disorders like TD and EPS), and one of, if not the most potent antihistamine on the planet, which is one reason why it makes you so tire and makes you gain so much weight.
1 No two medications will have the exact same mechanisms / methods of action. Sometimes a drug that is developed from the active metabolite of another, essentially inert med e.g. Invega (paliperidone) is a predigested form of Risperdal (risperidone) and is basically the same thing. However there is no good conversion of dosages between the two like there is for Tegretol (carbamazepine) and Trileptal (oxacarbazeine). Like Invega and Risperdal, Pristiq (desvenlafaxine) is the active metabolite of Effexor (venlafaxine), but Pristiq has a somewhat different mechanism of action than Effexor. Mainly it kicks Effexor's ass when it comes to how potent its inhibition of norepinephrine reuptake is.
All SSRIs are essentially interchangeable, making it possible to work out equivalent dosages, so you don't need to wait until you've cleared one drug to start another. But Celexa (citalopram) and Lexapro (escitalopram) are vastly more selective than Prozac (fluoxetine), and so the side effect profiles are very different. While most people couldn't tell the difference between Lexapro and Celexa, because Lexapro is a derivative of Celexa, a few people will respond differently to the two.
Date created Wednesday, 20 July 2011 at 11:21:11 Page Creator: Jerod Poore Last edited by: Jerod Poore
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All information on this site has been obtained through our personal experience and the experiences family, friends, what people have reported on various reputable sites all over teh intergoogles, the medications’ product information / summary of product characteristic (PI/SPC) sheets, and from sources that are referenced throughout the site. As such the information presented here is not intended as a substitute for real medical advice from your real doctor, just a compliment to it. You should never, ever, replace what a real doctor tells you with something from a website on the Internet. The farthest you should ever take it is getting a second opinion from another real doctor. Educate yourself - always read the PI/SPC sheet or patient information leaflet (PIL) that comes with your medications and never ever throw them away.
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1 While there are plenty of books to help you with hypochondria, for some reason there’s not much in the way of websites. Then again, staying off of the Internet is a large part of curing/managing the disorder.
2 Have I mentioned how open source operating systems for commercial applications is one of the dumbest ideas in the history of dumb ideas?
[begin rant] I rent a dedicated server for Crazy Meds. It’s sitting on a rack somewhere in Southern California along with a bunch of other servers that other people have rented. The hardware is identical, but no two machines have exactly the same operating systems. I don’t even need to see what is on any of the others to know this. If somebody got their server at the exact same time, with the exact same features as I did, I’m confident that there would be noticeable differences in some aspects of the operating systems. So what does this mean? For one thing it means that no two computers in the same office of a single company have the same operating system, and the techs can spend hours figuring out what the fuck the problem could be based on that alone. It also means that application software like IP board that runs the forum here has to have so many fucking user-configurable bells and whistles that even when I read the manual I can’t find every setting, or every location that every flag needs to be set in order for a feature to run the way I want it to run. And in the real world it means you can get an MBA not only with an emphasis on resource planning, but with an emphasis on using SAP - a piece of software so complex there are now college programs on how to use it. You might think, “But don’t people learn how to use Photoshop or Adobe Illustrator in college?” Sure, in order to create stuff. And in a way you’re creating stuff with SAP. But do you get a Bachelor of Fine Arts degree with an emphasis on Photoshop?
Back in the Big Iron Age the operating systems were proprietary, and every computer that took up an entire room with a raised floor and HVAC system, and had less storage and processing power than an iPhone, had the same operating system as every other one, give or take a release level. But when a company bought application software like SAP, they also got the source code, which was usually documented and written in a way to make it easy to modify the hell out of it. Why? Because accounting principles may be the same the world over, and tax laws the same across each country and state, but no two companies have the same format for their reports, invoices, purchase orders and so forth. Standards existed and were universally ignored. If something went wrong it went wrong the same way for everyone, and was easy to track down. People didn’t need to take a college course to learn how to use a piece of software.
I’m not against the open source concept entirely. Back then all the programmers read the same magazines, so we all had the same homebrew utilities. We even had the forerunner to QR Code to scan the longer source code. Software vendors and computer manufacturers sponsored conventions so we could, among other things, swap recipes for such add-ons and utilities. While those things would make our lives easier, they had nothing to do with critical functions of the operating system. Unless badly implemented they would rarely cause key application software to crash and burn. Whereas today, with open source everything, who the hell knows what could be responsible some part of a system failing. [/end rant]
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