What is the primary mechanism of action of selective serotonin reuptake inhibitors (SSRIs)?

Selective serotonin reuptake inhibitors (SSRIs) primarily function by inhibiting the reabsorption of serotonin in the brain. This mechanism allows for increased levels of serotonin in the synaptic cleft, which enhances serotonergic neurotransmission.

The increased availability of serotonin is thought to contribute to the antidepressant effects observed with the use of SSRIs, as serotonin is a key neurotransmitter involved in mood regulation. By blocking the reuptake process, SSRIs promote prolonged action of serotonin on postsynaptic receptors, ultimately leading to improved mood and anxiety-related symptoms in patients.

This mechanism differentiates SSRIs from other classes of antidepressants that may work through different pathways, such as those that increase serotonin production or directly influence receptor activity.