A group of older antipsychotic drugs—also referred to as “traditional” or “first-generation” antipsychotics (FGAs) and sometimes called neuroleptics—that work principally by blocking dopamine receptors in the brain. Examples include chlorpromazine and haloperidol. These medications have the potential to cause adverse side effects such as parkinsonian symptoms (muscle stiffness, rigidity, slowed gait, and tremor) and tardive dyskinesia (involuntary lip smacking, tongue movements, and upperextremity movements).