There is growing interest in the concept of network pharmacology, as opposed to specific pharmacological targets, as an important drug discovery paradigm. Also known as the “magic shotgun” paradigm, this strategy involves individual drugs interacting with multiple targets to achieve clinical benefit. Pharmacological promiscuity consistent with this paradigm has been suggested in vitro for antidepressants and anticonvulsants, which interact with many classes of ion channels (among other receptor targets). Although the link between certain “off-target” interactions and drug side effects is well-accepted, the potential linkage between promiscuity and clinical efficacy remains poorly understood. Here we summarize interactions of clinically useful anti-psychotic and anti-dementia medications with a diverse array of ligand- and voltage-gated ion channels. We hypothesize that promiscuous ion channel modulation may contribute to the efficacy of drugs used to treat psychosis and dementia.