Is Seroquel an agonist or antagonist? Psychology question?

We are pretty certain that it functions as an antagonist.

EDIT: I would like to point out (after seeing some of these other answers) that the specific pharmacokinetics and pharmacodynamics of this drug compound have not been been determined with an acceptable margin of certainty, therefore we cannot definitivley say that it is an antagonist. The mechanisim of action is still very much open for debate. This is why I said that we are pretty certain it functions as an antagonist. So just keep that in mind. It is not like an opiate where we know for certain it functions in an agonist manner.

Seroquel (Quetiapine) antagonizes dopamine D1 and D2 receptors, serotonin 5-HT2 and 5-HT1A receptors.

It is also an antagonist for alpha-1, alpha-2 adrenoceptors, which interact with norepinephrine (noradrenaline). There is also antagonist effects on the H1 histamine receptor.

So Seroquel is an antagonist for:

Dopamine

Serotonin

Norepinephrine

Histamine

Its an antagonist of both sertonin and dopamine receptors. Strongest at serotinin type 2a and dopamine type D2 receptors

It's an atypical anti psychotic medication