Desethoxy quetiapine, an active metabolite of the atypical antipsychotic quetiapine, primarily forms through the action of the cytochrome P450 (CYP) isoform CYP3A5. This compound binds to dopamine D2 receptors with an IC50 value of 1,330 nM. In vivo, desethoxy quetiapine at dosages of 20 and 40 mg/kg mitigates dopamine receptor agonist apomorphine-induced climbing behavior and ameliorates swimming deficits in mice, showcasing its potential modulatory effects on dopamine-mediated behaviors.