Table 1.

Summary of the antidepressants addressed in this review, highlighting some evidence in AD and the general mechanism of action, by drug class.

Drug	Drug Class	General Mechanism of Action	Examples of Evidence in AD
Fluoxetine Citalopram Escitalopram Paroxetine Fluvoxamine Sertraline	Selective serotonin reuptake inhibitors	This class of drugs inhibits the serotonin transporter (SERT) at the neurons, thereby enhancing the concentration of 5-HT in the synaptic cleft [77]	Increase in the hippocampus size, reduction of the amount of soluble Aβ peptide, improvements in memory, cognition, behavior, life quality, reduction of tau hyperphosphorylation, modulation of neuroinflammation
Desipramine Imipramine Amoxapine Amitriptyline	Tricyclic antidepressants	This class of drugs inhibits the serotonin transporter (SERT) and norepinephrine transporter (NET), enhancing the concentration of serotonin and norepinephrine in the synaptic cleft. Additionally, they are antagonists of α1 and α2, muscarinic, and H1 receptors [78]	Reduction in the production and accumulation of Aβ peptide, reduction in neuronal death and neuroinflammation, improvement in cognitive function, neuroprotection, cognition, and memory
Moclobemide Tranylcypromine	Monoamine oxidase inhibitors	This class of drugs inhibits monoamine oxidase enzyme, an enzyme responsible for the breakdown of several neurotransmitters such as 5-HT, NE and dopamine [79]	Increase in the proliferation of hippocampal progenitor cells, BDNF levels and reduction of neuronal death
Trazodone	Atypical antidepressant: serotonin-antagonist-and-reuptake-inhibitor [80]	This drug inhibits SERT and 5-HT2 receptors [80]	Delay of cognitive decline, improvement of insomnia
Ketamine	NMDA receptor antagonist	This drug acts mainly by antagonizing NMDA and glutamate receptors [81]	Behavioral improvement