Antidepressant medication

• What are selective serotonin reuptake inhibitors (SSRI)?

  They increase serotonin levels in the synaptic cleft.
• How does the presynaptic neuron work?

  Serotonin is stored in vesicles.

  Electrifal signal in neuron causes the vesicles to release serotonin into the synaptic cleft.
• Why do SSRI’s block reuptake?

  So there is more serotonin left in the synaptic cleft.