Monoaminergic means "working on monoamine neurotransmitters", which include serotonin, dopamine, and norepinephrine (and epinephrine), as well as melatonin.
A monoaminergic, or monoaminergic drug, is a chemical which functions to directly modulate the serotonin, dopamine, norepinephrine/epinephrine, and/or melatonin neurotransmitter systems in the body or brain. Monoaminergics include catecholaminergics (which can be further divided into adrenergics and dopaminergics), serotonergics, and melatonergics. A specific example are monoamine oxidase inhibitors (MAOIs), which affect the activity of all four of these systems.
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