Antihedonics

Antihedonics are drugs which serve the primary purpose of
impairing a person's ability to feel pleasure, and especially sexual pleasure.
Such drugs are almost always promoted and prescribed under
spurious pretenses by psychopaths though.

There are two major classes of antihedonics,
which are the serotonin reuptake inhibitors (SRIs)
and the D2 receptor antagonists, AKA "major tranquilizers".
The SRIs exert their antihedonic effect via desensitizing the
5-ht2a, 5-ht2b, and 5-ht2c receptors which are involved in the
dopaminergic pleasure system.
The D2 receptor antagonists exert their antihedonic effect via
increasing prolactin in the brain, which inhibits dopaminergic function.

The antihedonic effects of SRIs are sometimes permanent,
in which case the condition is called post-SRI syndrome.
The antihedonic effects of D2 receptor antagonists sometimes last for some time
after the drug-consumption has ceased, but are rarely permanent.

SRI antihedonics are typically spuriously marketted as "antidepressants",
whereas D2-antagonist antihedonics are typically spuriously marketted as "antipsychotics".