Some science behind the scenes

SRIs

A serotonin reuptake inhibitor (SRI) is according to Wikipedia:

a type of drug which acts as a reuptake inhibitor of the neurotransmitter serotonin (5-hydroxytryptamine (5-HT)) by blocking the action of the serotonin transporter (SERT). This in turn leads to increased extracellular concentrations of serotonin and, therefore, an increase in serotonergic neurotransmission.

They can be selective and non selective.

 The selective SRIs are described under the heading of anti-depressants, since this is the purpose most of them serve, they are then called  SSRIs. 

The non selective SRIs include both legal and illegal drugs.  As these drugs are grouped under the purpose they serve.

Observations

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