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Changes in the temporal parameters of EEG microstates are observed in various psychiatric illnesses, including psychotic disorders. These changes have also been observed in individuals with a clinical or genetic high risk for psychosis. It is unclear whether dopamine abnormalities, distinctive of psychotic disorders, contribute to microstate alterations. Fifty-eight healthy participants (M: F = 32:26) took part in a single-dose drug challenge study. Using a randomized, double-blind, cross-over, and placebo-controlled design, participants received the dopamine precursor L-DOPA (100 mg), the dopamine antagonist haloperidol (2 mg), and a placebo. Resting-state (10 min, eyes-closed) 64-channel EEG was recorded at peak drug effects. We calculated temporal parameters (coverage, duration, and occurrence) of 5 microstate classes (A-E) and compared them between drug conditions using linear mixed-effect models. Significant group x class interactions were observed for all parameters. Compared to placebo, parameters of microstate B were decreased under L-DOPA (duration and occurrence) and haloperidol (coverage, duration, and occurrence). Coverage and occurrence of microstate C were reduced under L-DOPA compared to haloperidol and placebo. Parameters of microstate E were reduced under L-DOPA compared to haloperidol (coverage and occurrence) and placebo (coverage, duration, and occurrence). Both haloperidol and L-DOPA increased all parameters of microstate D, compared to placebo. Our results show that resting-state EEG microstates are modulated by dopaminergic drugs. However, extrapolations from healthy controls to patients with psychotic disorders are complicated by various factors. Further studies should investigate the (long-term) effects of haloperidol and other antipsychotics on EEG microstates in patients with psychotic disorders.