[PBF]

Check those charts out, they are really intersting.  From Ian Chovil's schizophrenia site.  Thanx Ian!

Relative receptor occupancy rates for Atypicals

D2 and 5h2T Occupancy (with antipsychotic threshold and EPS threshold doses)

Chemical activity of antipsychotisc

PBF

[Unregistered]

Jeez, Olanzapine's pretty much a scatter gun, isn't it? Hit everything just in case...

[AirMarshall]

Most Coool! Easy to understand charts. Even with a biology degree I find the pharmacology tough going, and mostly boring, but these are simple to understand.

I was going to say the same thing about these meds 'shotgunning' receptors. We are no longer in the "stone age" of psych meds, but clearly the future holds the promise of more better targeted drugs with attendant lower side effects.

a.m.

[LikeMinded]

I wouldn't be bashing Zyprexa (or Risperdal, for that matter) because they both gun in different places.

The new hawtness in AD treatment is agomelatine (Valdoxan in Europe), which blocks the 5HT2 receptor (I forget which subtype/s, but I do know that Risperdal only will block the 5HT2C receptor). The other end of the agomelatine molecule, interestingly, activates the MT1 and MT2 melatonin receptors... it's supposed to regulate sleep cycle.

In any event, there are researchers here and there speculating that 5HT2 is responsible for some portions of psychosis (namely hallucinations). Specifically, I'd guess 5HT2A... only since I've read that psilocybin (the active ingredient in magic 'shrooms) and LSD are powerful activators of it... I do understand they both cause visual interestingness.

[etkearne]

I have actually printed out Chart II (which I found on another website awhile back) and brought it to show my psychiatrist that, yes, it is very possible to get EPS and prolactin elevation (man boobs) from Zyprexa at 20mg a day. One time, I was actually instructed to take 40mg (the doctor, who is actually quite good was hung up on the atypical crap still) and had essentially the same thing as those scary videos of people on Haldol in psych wards in the 70s. I felt like I wanted to lash out and scream my guts out from the akathisia, but all I could do was sit in a chair and shake. It took 3 days for that to go away.

Since I showed my psychiatrist that chart (an another, which I may post, showing numerical values on binding affinity), he took me off of the Zy, and now we are using mood stabilizers. I am bipolar, not schizophrenic, however, my manias are very psychotic and I lose complete touch with the world.

[etkearne]

This is the chart I was talking about. Lesser values mean tighter binding affinity. For example, Seroquel is not very potent at all at binding to D₂. However its high affinities to the "yellow shaded" receptors mediate extrapyramidal side effects to a degree. It is debateable whether 5-HT2A really helps with EPS. I read a paper that says it is really 5-HT2C antagonism which can counteract the tighter binding to D₂. You can see why they say Clozapine is "the best" for treatment resistant folks. All of the "anti-EPS" receptors are revved up extensively, but D₂ is only moderately binded to. Therefore, a large dose of Cloazapine would be required to get that magic 60% D₂ antagonism needed for it to work, but by that point, any EPS would be completely subdued by the intense antagonism of the "yellow shaded" receptors. I just wish this chart had 5-HT2C, since the newer literature supports this as a real key to future research.