Quetiapine (Seroquel) is associated with affecting which neurotransmitter systems?

• A. Dopamine and Serotonin
• B. GABA and Glutamate
• C. Norepinephrine and Acetylcholine
• D. Endorphins and Enkephalins

Answer: (A)

Quetiapine is an atypical antipsychotic whose therapeutic actions come mainly from blocking dopamine D2 receptors and serotonin 5-HT2A receptors in the brain. This dual action dampens dopaminergic activity in pathways involved in psychosis while modulating serotonin transmission, which helps with mood stabilization and reduces the risk of extrapyramidal symptoms compared with older antipsychotics. So the neurotransmitter systems most affected are dopamine and serotonin. While quetiapine also interacts with other receptors (such as histamine and alpha-adrenergic receptors) that contribute to sedation and autonomic effects, these are secondary to its main antipsychotic action. It does not primarily target GABA/glutamate, norepinephrine/acetylcholine, or endogenous opioid systems.