Pharmacology - Antipsychotics as Amphetamine antidote?

[Boca Bitch]

I've read of some studies utilizing the doperminergic antagonist properties of antipsychotics as a method of sedation and lowering toxicity from an amphetamine overdose.

Up until the most recent ones I've come across, medicine still stands divided, with some experts preferring to treat OD symptomatically and use GABA agonist as sedatives/anticonvulsants (if necessary) until the amphetamine wears off.

Have there been any more studies done recently? They're rather difficult to find online, so I was wondering if anyone had the luck of stumbling upon one.

Reputation Comments on this post:

a most excellent thread, thanks for bringing it up

[oggy]

It wouldn't work with some anti psychotics as they take weeks or months to build up in the system, haloperidol might work but I doubt it. When SWIM was on the anti psychotics he took stimulants from a legal high shop and they were still just as effective. Haloperidol made things more trippy for SWIM. Maybe SWIM was wrongly diagnosed.

You'd be better with a low dose of the faster acting benzodiazepines.

[Synchronium]

Oggy: If your legal stimulents had nothing to do with your dopamine receptors, then there's no wonder haloperidol did nothing.

Actual amphetamine causes an increase in basal dopamine levels, so a dopamine antagonist such as haloperidol would stop a lot of the effects.

[oggy]

SWIM was on olanzapine at the time, he took those legal dove pills you buy in head shops and they're meant to work on the dopamine receptors. I said haloperidol "might" work!

[Hollow Hippie]

Antipsychotics would block a lot of the psychological symptoms but cardiac symptoms would require something affecting the alpha-andrenic (sp?) receptors.

Reputation Comments on this post:

important point, one needs to look at the full spectrum of effects to treat an OD

[Synchronium]

Phentolamine or Phenoxybenzamine, perhaps?

[Boca Bitch]

Or.. Clonidine.. because of its potent anti-hypertensive effects.. Interesting point Hippie!! Thank you.

[bryanbabylon]

I read everything I can come across about antipsychotics (thats how I found this site.) Antipsychotics are used to combat psychosis resulting from acute-heavy or long term use of amphetamine (in specific) and phenethalamine (in general) drugs. Antipsychotics do not make you come down from a speed or psychedelic high, they take weeks to months for noticeable effects to occur, and they have a REALLY nasty side effects profile. Please do not take antipsychotics if they are not prescribed to you.

[Boca Bitch]

Originally Posted by bryanbabylon

I read everything I can come across about antipsychotics (thats how I found this site.) Antipsychotics are used to combat psychosis resulting from acute-heavy or long term use of amphetamine (in specific) and phenethalamine (in general) drugs. Antipsychotics do not make you come down from a speed or psychedelic high, they take weeks to months for noticeable effects to occur, and they have a REALLY nasty side effects profile. Please do not take antipsychotics if they are not prescribed to you.

The question was posed strictly for overdose scenario in a hypothetical (under medical supervision) situation. After further research... I've come to the conclusion myself that anti-psychotics cannot/should not be administered to one suffering from amphetamine overdose. And there are plenty of instant-acting anti-psychotics administered IV.

The mechanisms of action are not directly related for the two, anti-psychotics are far too broad range in their effects. The anticholinergic properties could even make it a lethal combination.... causing tachycardia and subsequent heart failure. Which is why beta-blockers are STRICTLY contradicted in all stimulant OD cases.

Treatment is/needs to be focused on vasodialation, hydration, heart rate monitoring, axiolysis, renal monitering (depending on dose), and proper flushing of the system.

Obviously, as is standard with any ER procedure, saline would be necessary for hydration (although w/o glucose, as that would result in hyperglycemia). A benzodiazepine would be administered for reduction of anxiety, while also providing mild vasodialation. If necessary, I'm sure another non-adrenergic vasodialator would be administered, such as papaverine.

[Hollow Hippie]

Anti-psychotics are def do not take weeks or months to work, they can take a while to reach clinical efficiency for certain conditions, but they go to work as soon as they enter the bloodstream.

Reputation Comments on this post:

good clarification

[lostmente]

for most people who take anti-psychotics, the first few doses knock you out pretty well. Swim has given people olanzapine to terminate trips/speed freakouts. They calm down within an hour and are out within 2 hours. It seems to do them well as they wake up pretty calm and happy, but groggy

lostmente added 2 Minutes and 13 Seconds later...

swim is a believer that the fear in those circumstances is often the killer but is not knoweldgeable enough to speak of the interactions...

however, swim did have a bad reaction when he abused seroquil and mdma. The shrink later said it was probably a cholinergic syndrome

[Jatelka]

Antipsychotics in conjunction with amphetamines can cause hypertensive crises.
Bear in mind, that they can also cause hypertension WITHOUT amphetamine in the mix

(Sources: "Paradoxical hypertension associated with clozapine". Am J Psychiatry 1994;151:148, Hypertension associated with clozapine. Am J Psychiatry 1996;153:1368-1369, Paradoxical hypertension associated with clozapine. Med J Aust 1997;166:278)

Although the sources listed above relate to Clozapine, there are numerous adverse reactions reported with other antipsychotics, including: Risperidone and Quetiapine

Antipsychotics should ABSOLUTELY not be used for amphetamine freak-out.

Boca Bitch is quite right in stating that a benzodiazepine would be the way forward

Amphetamines also increase the risk of acute dystonia with antipsychotics: So another reason they should not be used

(Source: "Stimulant-Atypical Antipsychotic Interaction and Acute Dystonia" Journal of the American Academy of Child & Adolescent Psychiatry: June 2005 - Volume 44 Issue 6 - pp 510-511)

[chibi curmudgeon]

Originally Posted by Jatelka

Although the sources listed above relate to Clozapine, there are numerous adverse reactions reported with other antipsychotics, including: Risperidone and Quetiapine

Clozapine's reeeeally weird, though, and most antipsychotics, I think both 1st and 2nd gen, have anti-adrenergic effects. I'm looking at a guide (Black Book of Psychotropic Dosing and Monitoring, 10th ed.) that says they potentiate clonidine and decrease the effects of amphetamines. Are you saying antipsychotics shouldn't be used because they don't work, or because they have hideous side effects? I totally agree that they're shitty drugs, but I've never seen anything to suggest they won't stop amphetamine psychosis.

[Hollow Hippie]

Originally Posted by chibi curmudgeon

Clozapine's reeeeally weird, though, and most antipsychotics, I think both 1st and 2nd gen, have anti-adrenergic effects. I'm looking at a guide (Black Book of Psychotropic Dosing and Monitoring, 10th ed.) that says they potentiate clonidine and decrease the effects of amphetamines. Are you saying antipsychotics shouldn't be used because they don't work, or because they have hideous side effects? I totally agree that they're shitty drugs, but I've never seen anything to suggest they won't stop amphetamine psychosis.

They certainly will stop amphetamine psychosis, but as said before you have to look at other aspects of amphetamine toxicity.

[onzero]

both drugs are more complicated than that.

anti-psychotics are more varied in their mechanism of action, with more dopamine receptor specificity, but also usually affecting a wide range of other receptors to a small degree (histamine, muscarine, serotonin, etc.)

so it depends WHICH anti-psychotic you're talking about

there's 1st gen, 2nd gen, the 2nd gen each drug has its own individual mechanism of action.

you would want to know which one to use, i would think a typical antipsychotic would be a safe choice (haloperidol) something like quetiapine or clozapine not necessarily so.

amphetamines/cocaine are very similar in their MOA particularly with regards to receptor targeting.


most anti-psychotics are "messy" drugs, in that they are very unspecific (relatively speaking compared to many drugs) and act on a wide array of receptors with a wide array of variability of effects upon those receptors.