a The table is organized using a binary system for simplicity. For each mechanism of action listed, a drug is designated as having (+) or not having (-) a potent effect under clinically relevant conditions. The presumption is based on the preclinical (in vitro) pharmacology of the drug and the likelihood that it reaches sufficient concentration in vivo to affect this site of action given its in vitro potency. A (+) designation is made if 1) the drug affects a designated biological site more potently than its presumed antidepressant mechanism of action, and/or 2) if the in vitro potency for a designated biological site is within one order of magnitude of the drug potency for the presumed antidepressant mechanism(s) of action. The in vitro data on antidepressant pharmacodynamics was taken for Bolden-Watson and Richelson (9) and deBoer, et al (14).

b Monoamine oxidase inhibitors are not included in the table. Although they potentiate serotonin, norepinephrine, and dopamine, they do not share any mechanism of action in common with any other antidepressant agents.

c AMI = amitriptyline, DES = desipramine, SER = sertraline, VEN = venlafaxine, NEF = nefazodone, MIR = mirtazapine

d NE = norepinephrine

e SE = serotonin

f 5-HT = serotonin receptor; subsequent number and letter designate receptor subtype

g designation (+ or -) refers to the drug potency as a receptor antagonist

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published 2000