Aripiprazole vs Risperidone: what is the difference?

How they differ

Both are atypical antipsychotics and they treat the dopamine receptor in opposite ways. Risperidone is a straightforward D2 blocker with strong 5-HT2A blocking added, so at higher amounts it behaves much like an older antipsychotic, including a marked rise in prolactin. Aripiprazole is a partial agonist: it occupies the same receptor and produces a low level of activation, damping signalling where dopamine is high and supporting it where dopamine is low. That mechanism is why aripiprazole tends to be more activating and less prolactin raising, while risperidone is the more sedating. Aripiprazole is the heavier of the two at 448.4 against 410.5.

Side by side

Common questions

What is the difference between Aripiprazole and Risperidone?

Both are atypical antipsychotics and they treat the dopamine receptor in opposite ways. Risperidone is a straightforward D2 blocker with strong 5-HT2A blocking added, so at higher amounts it behaves much like an older antipsychotic, including a marked rise in prolactin. Aripiprazole is a partial agonist: it occupies the same receptor and produces a low level of activation, damping signalling where dopamine is high and supporting it where dopamine is low.

Is Aripiprazole bigger than Risperidone?

Aripiprazole is the heavier molecule, 448.4 g/mol against 410.5 g/mol for Risperidone. Aripiprazole is C23H27Cl2N3O2 and Risperidone is C23H27FN4O2.