AP Topic Index | Common uses of APs ›

Like antidepressants (ADs) and anticonvulsants / antiepileptic drugs (AEDs), antipsychotics (APs) are broken up into different classes based upon things like chemical structure and how they work in your brain. Like AEDs there is some overlapping membership. Currently the primary classification of APs is a combination of age and how they work (pharmacodynamics).

1.  First Generation Antipsychotic Agents / Neuroleptics

With the exception of lithium carbonate and Haldol (haloperidol), all first generation antipsychotic agents (FGAs), also known as standard antipsychotics and typical antipsychotics, were thought to work in the exact same way - binding to D2 dopamine, M1 muscarine, H1 histamine, and maybe even a little alpha-1 noradrenergic receptors to interfere with the reception of those neurotransmitters (D2, M1, H1 and α1 antagonists). The only differences being chemical structure, potency at the various receptors, where in your brain this would happen, and each drug’s pharmacokinetics. Haldol is different in that it doesn’t do much as far as M1 and H1 are concerned, and is a lot more potent in binding to alpha-1, so its side effect profile is somewhat different.

With better technology and more competition for grant money, researchers are looking back at FGAs to see how they work. Turns out they all don’t work the same way after all and some (loxapine, chlorprothixene, e.g.) are like Haldol in that they are a lot more like atypical / second-generation antipsychotics than FGAs.

1.1  List of First Generation / Standard / Typical Antipsychotic Agents

• Thorazine (chlorpromazine HCl)
• fluphenazine decanoate
• Prolixin (fluphenazine HCl)
• Serentil (mesoridazine besylate)
• Trilafon (perphenazine)
• Compazine (prochlorperazine)
• Mellaril (thioridazine HCl)
• Stelazine trifluoperazine HCl
• Haldol (haloperidol)
• haloperidol decanoate
• Loxitane (loxapine succinate)
• Moban (molindone HCl)
• Orap (pimozide)
• Navane (thiothixene)
• Serpasil (reserpine)
• Taractan / Truxal (chlorprothixene)
• Sordinol (clopenthixol)
• Depixol / Fluanxol (flupentixol)
• flupentixol deconate
• Clopixol / Acuphase (zuclopenthixol)
• zuclopenthixol deconate

Subsets of FGAs:

1.2  Phenothiazines¹

• Thorazine (chlorpromazine HCl)
• fluphenazine decanoate
• Prolixin (fluphenazine HCl)
• Serentil (mesoridazine besylate)
• Trilafon (perphenazine)
• Compazine (prochlorperazine)
• Mellaril (thioridazine HCl)
• Stelazine trifluoperazine HCl

1.3  Thioxanthenes

• Navane (thiothixene)
• Taractan / Truxal (chlorprothixene)
• Sordinol (clopenthixol)
• Depixol / Fluanxol (flupentixol)
• flupentixol deconate
• Clopixol / Acuphase (zuclopenthixol)
• zuclopenthixol deconate

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2.  Second Generation Antipsychotic Agents / Neuroleptics

Second generation antipsychotic agents (SGAs), more commonly known as atypical APs (AAPs), are APs that do a lot more than FGAs. I.e. they are broad-spectrum antagonists of dopamine, alpha-noradrenergic, and serotonin receptors. Except for Risperdal (risperidone) and Invega (paliperidone) - which is Risperdal’s active metabolite (i.e. predigested Risperdal) in pill form - no two of them work the same way. Clozaril (clozapine), Zyprexa (olanzapine) and Saphris (asenapine) are fairly close in pharmacodynamics, and they bind to practically every neurotransmitter receptor you’ve got, while Risperdal / Invega don’t do much more than Haldol.

2.1  List of Second Generation / Atypical Antipsychotic Agents

• Zyprexa (olanzapine)
• Seroquel (quetiapine fumarate)
• Geodon (ziprasidone)
• Fanapt (iloperidone)
• Saphris (asenapine)
• Risperdal (risperidone)
• Invega (paliperidone)
• Latuda (lurasidone HCl)
• Clozaril (clozapine)
• Solian (amisulpride)
• Asendin (amoxapine) - See below

While officially classified as a tetracyclic antidepressant (TCA), Asendin (amoxapine) is being unofficially classified as an atypical antipsychotic by Stahl and other pharmacologists, based upon its efficacy in treating schizophrenia and mechanism of action.

3.  Third Generation Antipsychotic Agents / Neuroleptics

Third generation antipsychotic agents (TGAs) are APs that are both dopamine antagonists (interfering with dopamine reception) and partial agonists (stabilizing dopamine reception). Abilify (aripiprazole) is the first TGA on the market, several more are under development / in various clinical trial phases.

• Abilify (aripiprazole)

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4.  APs Categorized by Potency

Regardless of generation, APs are also categorized by how strong they are. Remember: potency does not equal efficacy.

4.1  List of high-potency antipsychotics / neuroleptics

4.2  List of low-potency antipsychotics / neuroleptics

5.  AP Equivalents

6.  Which Is Better, Standard APs or Atypical APs (AAPs)?

The simple answer: whichever one works for you, and in a perfect world you wouldn’t need an AP in the first place. Generally speaking if an AP is the appropriate drug and your symptoms aren’t particularly complicated, good old Thorazine (chlorpromazine HCl) would probably be the way to go. On the flipside, if you’re so batshit crazy that someone else is reading this page², then something like Zyprexa, Saphris, or even Clozaril (clozapine) might be needed.
In general AAPs tend to suck less, but that is at such an actuarial level (i.e. from the point of view of insurance companies and HMOs dealing with thousands of people]], there’s no way you can determine which class of med will suck less for you unless you already have a medical history.

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Page created by: Jerod Poore. Date created: 31 December 2010 Last edited by: Classifications of Antipsychotic Drugs is copyright 2011 Jerod Poore

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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]