Exploring What Psychiatric Medication Is Used for Nausea?

October 10, 2025 •

3 min read

Approximately 80% of chemotherapy patients experience chemotherapy-induced nausea and vomiting (CINV), highlighting a significant need for effective antiemetic therapies. In certain cases, an unexpected solution comes from an answer to the question: What psychiatric medication is used for nausea?. These medications, often targeting the brain's neurotransmitter systems, can provide relief by blocking signals that trigger the body's vomiting response.

Quick Summary

Certain psychiatric drugs, such as the antipsychotics prochlorperazine, chlorpromazine, and olanzapine, have potent anti-nausea properties by blocking key neurotransmitters in the brain.

Key Points

Dopamine Antagonists: First-generation antipsychotics like prochlorperazine and chlorpromazine block dopamine receptors in the brain to control severe nausea and vomiting.
Multi-Receptor Action: The atypical antipsychotic olanzapine is used off-label for nausea because it blocks multiple receptors, including dopamine and serotonin, making it highly effective for complex cases like chemotherapy-induced nausea.
Specialized Uses: Olanzapine is particularly valued for managing nausea from chemotherapy and in palliative care due to its potent antiemetic effects.
Antihistamine Alternatives: Hydroxyzine, an antihistamine used for anxiety, also possesses mild anti-nausea properties and can be used in some psychiatric contexts for this symptom.
Balancing Benefits and Risks: These medications carry risks such as sedation and potential movement disorders, and their use for nausea must be carefully managed by a healthcare professional.
Addressing Refractory Nausea: For patients with difficult-to-treat nausea that doesn't respond to standard antiemetics, psychiatric drugs like olanzapine or phenothiazines can be a critical part of the treatment plan.

The Unexpected Link Between Psychiatric Drugs and Nausea

While many people associate psychiatric medications with treating mental health conditions, several agents within this class possess powerful antiemetic properties. This dual function is primarily due to their mechanism of action, which involves modulating neurotransmitter systems in the brain. The complex circuitry controlling nausea and vomiting, centered in the brain's chemoreceptor trigger zone (CTZ), relies on neurotransmitters like dopamine and serotonin. Psychiatric drugs that block these neurotransmitter receptors can effectively suppress nausea.

Key Psychiatric Medications Used for Nausea

Prochlorperazine (Compazine)

Prochlorperazine is a first-generation (typical) antipsychotic with FDA approval for two distinct purposes: treating psychotic conditions like schizophrenia and controlling severe nausea and vomiting. It functions as a dopamine antagonist, primarily blocking dopamine D2 receptors in the chemoreceptor trigger zone. This action effectively shuts down the signals that cause the body to feel nauseated and vomit. It is a well-established antiemetic that is used in both inpatient and outpatient settings for various causes of nausea.

Olanzapine (Zyprexa)

Unlike prochlorperazine, olanzapine is an atypical (second-generation) antipsychotic primarily approved for schizophrenia and bipolar disorder. Its use for nausea is considered off-label, but is strongly supported by clinical evidence, particularly for chemotherapy-induced nausea and vomiting (CINV) and nausea in palliative care settings. Olanzapine works by blocking multiple neurotransmitter receptors, including those for dopamine and serotonin. This multi-receptor action makes it particularly effective for complex and refractory cases of nausea. National guidelines, such as those from the American Society of Clinical Oncology (ASCO), now recommend olanzapine in combination with other antiemetics for patients receiving highly emetogenic chemotherapy.

Chlorpromazine (Thorazine)

Chlorpromazine is another first-generation antipsychotic with a long history of use for managing psychiatric conditions. Similar to prochlorperazine, it has an FDA-approved indication for controlling nausea and vomiting. Its antiemetic effect is attributed to the blockade of multiple receptors, including dopamine D2, histamine H1, and muscarinic M1 receptors in the brain's vomiting center. It is used for various types of nausea and vomiting, including postoperative and chemotherapy-related symptoms.

Hydroxyzine (Vistaril)

Hydroxyzine is an antihistamine that is also frequently used for anxiety due to its sedative properties. Its primary mechanism involves blocking histamine H1 receptors, but it also has anti-nausea effects. While not as potent for severe nausea as the antipsychotics, it can be a useful adjunct treatment for anxiety-related nausea or as a mild antiemetic.

Potential Risks and Considerations

While these medications can be highly effective, they are not without side effects, and should only be used under a doctor's supervision.

Sedation: Many of these drugs can cause drowsiness, especially olanzapine and hydroxyzine.
Movement disorders: First-generation antipsychotics like prochlorperazine and chlorpromazine carry a higher risk of extrapyramidal symptoms and tardive dyskinesia, especially with long-term use.
QTc prolongation: Some dopamine antagonists, including older antipsychotics, have a risk of affecting heart rhythm, requiring careful monitoring.
Other side effects: Common side effects vary by medication and can include dry mouth, constipation, and dizziness.

Comparison of Psychiatric Antiemetics


Feature	Prochlorperazine (Compazine)	Olanzapine (Zyprexa)	Chlorpromazine (Thorazine)
Drug Class	First-Gen Antipsychotic	Atypical Antipsychotic	First-Gen Antipsychotic
FDA Status for Nausea	Approved	Off-Label	Approved
Mechanism of Action	Blocks dopamine (D2) receptors in the CTZ	Blocks dopamine, serotonin, and other receptors	Blocks dopamine (D2), histamine (H1), and other receptors
Common Use for Nausea	Severe nausea and vomiting	CINV, palliative care nausea	Various types of nausea and vomiting
Primary Psychiatric Use	Schizophrenia, anxiety	Schizophrenia, bipolar disorder	Schizophrenia, bipolar disorder
Key Side Effects	Movement disorders, sedation	Sedation, weight gain	Movement disorders, sedation

Conclusion

The use of psychiatric medications for nausea demonstrates the intricate connections within the human nervous system. By targeting neurotransmitter receptors, particularly those for dopamine and serotonin, certain antipsychotics like prochlorperazine, chlorpromazine, and olanzapine can effectively manage and prevent nausea and vomiting. While prochlorperazine and chlorpromazine have long-standing approval for this use, olanzapine's off-label application for chemotherapy and palliative care nausea has gained significant clinical support. It is crucial for patients to understand the dual nature of these drugs and to discuss their use and potential side effects with their healthcare provider. For complex or refractory nausea, these psychiatric agents can be a valuable tool in improving a patient's quality of life.

Optional Link: For more detailed pharmacological information on these medications, consult the National Institutes of Health (NIH) resources.

Frequently Asked Questions

Psychiatric medications, particularly antipsychotics, work by blocking certain neurotransmitter receptors in the brain, such as dopamine and serotonin receptors. Since the brain's chemoreceptor trigger zone, which controls nausea, relies on these same neurotransmitters, blocking them effectively suppresses the feeling of nausea.

Prochlorperazine is a first-generation antipsychotic with FDA approval specifically for nausea and vomiting, while olanzapine is a second-generation antipsychotic used for nausea in an off-label capacity. Olanzapine's multi-receptor action often makes it effective for more refractory types of nausea, such as CINV.

Yes, its use for nausea, particularly CINV, is considered safe and is recommended by major oncology guidelines. However, it is an off-label use and requires careful management by a physician, with a focus on short-term use for nausea to minimize long-term side effect risks.

Yes, first-generation antipsychotics like prochlorperazine and chlorpromazine carry a higher risk of extrapyramidal side effects, including involuntary movements. While newer medications like olanzapine have a lower risk, long-term use at higher doses can still pose some risk.

While many antidepressants can cause nausea as a side effect, some, particularly certain tricyclic antidepressants, have been explored for chronic unexplained nausea and vomiting (CUNV). However, this is less common and primarily used for refractory cases.

Yes, sedation is a common side effect, especially with medications like olanzapine and hydroxyzine. This is often utilized as a benefit in palliative care settings but can be a drawback for active patients.

These drugs are typically reserved for more severe or refractory cases of nausea, or when a patient needs the benefit of targeting multiple neurotransmitter pathways. For instance, olanzapine is often used in combination with other antiemetics for highly emetogenic chemotherapy.