Phenothiazines are a class of medications primarily used to treat mental health disorders, such as schizophrenia and bipolar disorder. They work by blocking certain neurotransmitters in the brain, particularly dopamine, which helps reduce symptoms like hallucinations and agitation. In addition to their psychiatric uses, phenothiazines can also be prescribed for nausea and vomiting, as they have antiemetic properties. Common examples include chlorpromazine and promethazine. While effective, these medications can have side effects, including sedation and movement disorders, which require careful monitoring by healthcare providers.