What is the effect of SSRIs on serotonin?

What is the effect of SSRIs on serotonin?

• A. They increase degradation of serotonin.
• B. They block serotonin synthesis.
• C. They inhibit the reuptake of serotonin, increasing its availability in the synaptic cleft.
• D. They block serotonin receptors.

Answer: (C)

SSRIs work by blocking the serotonin transporter on the presynaptic neuron, which normally reabsorbs serotonin after it’s released. By inhibiting this transporter, more serotonin remains in the synaptic cleft to bind postsynaptic receptors, boosting serotonergic signaling. This raised availability in the synapse, rather than increasing breakdown, reducing synthesis, or blocking receptors, is what differentiates SSRIs’ action. Over time, the sustained serotonin signaling leads to downstream changes that contribute to their therapeutic effects.

SSRIs work by blocking the serotonin transporter on the presynaptic neuron, which normally reabsorbs serotonin after it’s released. By inhibiting this transporter, more serotonin remains in the synaptic cleft to bind postsynaptic receptors, boosting serotonergic signaling. This raised availability in the synapse, rather than increasing breakdown, reducing synthesis, or blocking receptors, is what differentiates SSRIs’ action. Over time, the sustained serotonin signaling leads to downstream changes that contribute to their therapeutic effects.