What is the mechanism of action for PCP?

The mechanism of action for PCP, or phencyclidine, is that it acts as an NMDA antagonist. This means that it primarily blocks the N-methyl-D-aspartate (NMDA) receptor, which is crucial for glutamate signaling in the brain. Glutamate is the main excitatory neurotransmitter in the central nervous system, and it plays a critical role in synaptic plasticity, memory, and learning.

By inhibiting NMDA receptors, PCP disrupts normal excitatory neurotransmission, leading to various effects such as dissociation, hallucinations, and alterations in perception. This activity can contribute to cognitive dysfunction and affect motor coordination, often mimicking symptoms of psychosis. The dissociative effects observed with PCP use are largely attributable to its action on these glutamatergic systems.

Understanding this mechanism is vital in addiction medicine as it highlights the neurobiological pathways involved in PCP’s effects and the potential risks associated with its use. Other options like dopamine or norepinephrine reuptake inhibition pertain to different classes of substances and are not relevant to PCP's action, while nitric oxide synthase activation does not describe any known pharmacological effect of PCP.