What is Stemetil used for? A Comprehensive Guide to Prochlorperazine

October 6, 2025 •

4 min read

Stemetil, the brand name for the active ingredient prochlorperazine, is a potent phenothiazine medication widely used for its anti-sickness and anti-vertigo properties. Originally developed as an antipsychotic, its powerful effects on the central nervous system also make it highly effective for controlling severe nausea and vomiting caused by a variety of conditions, as well as managing symptoms of certain inner ear disorders.

Quick Summary

Stemetil (prochlorperazine) is a prescription medication primarily used to control severe nausea, vomiting, and vertigo associated with inner ear disorders like Meniere's disease. It also has applications for treating certain psychotic disorders and short-term anxiety.

Key Points

Primary Uses: Stemetil is mainly used to treat severe nausea, vomiting, and vertigo from causes like inner ear problems, chemotherapy, and surgery.
Active Ingredient: The active component of Stemetil is prochlorperazine, a phenothiazine medication.
Mechanism of Action: It works by blocking dopamine receptors in the brain, interrupting the signals that cause feelings of sickness.
Side Effects: Common side effects include drowsiness and dizziness, while long-term or high-dose use carries a risk of serious movement disorders like tardive dyskinesia.
Important Warnings: Stemetil should be used with caution in elderly patients and is not recommended for children under two years old or for long-term anxiety treatment.
Formulations: It is available in various forms, including oral tablets, buccal tablets, and injections, with dosage depending on the condition treated.
Prescription Only: In most cases, Stemetil is a prescription-only medication and should not be used without medical advice.

Understanding Stemetil (Prochlorperazine)

Stemetil is a brand name for the drug prochlorperazine, which belongs to a class of medications known as phenothiazines. While it is a potent antipsychotic, its most common modern applications leverage its powerful antiemetic (anti-nausea) and anti-vertigo properties. It functions by blocking the action of dopamine in the brain, which affects not only mood and behavior but also the part of the brain responsible for triggering vomiting.

The Primary Uses of Stemetil (Prochlorperazine)

Stemetil is prescribed for several key conditions due to its wide-ranging effects on the central nervous system. Its use varies depending on the specific formulation, such as oral tablets, buccal tablets (dissolve in the cheek), or injections.

Controlling Severe Nausea and Vomiting

One of the most common and effective uses of Stemetil is to alleviate severe nausea and vomiting. This includes:

Chemotherapy-Induced Nausea: For patients undergoing cancer treatment, Stemetil can be used to manage both acute and delayed nausea and vomiting.
Post-Operative Nausea: The drug can be administered before or after surgery to prevent or treat sickness caused by general anesthesia.
Radiation Therapy: It is also effective for managing nausea and vomiting resulting from radiation treatment.
Migraine-Related Sickness: While sometimes considered an off-label use, Stemetil is often recommended for treating the nausea and vomiting that accompany severe migraine headaches.

Managing Vertigo and Inner Ear Disorders

For individuals suffering from disorders that affect balance, Stemetil provides significant relief by calming the signals sent from the inner ear to the brain's vomiting center.

Meniere's Disease: A condition causing episodes of vertigo, tinnitus, and hearing loss, Meniere's disease is effectively managed with Stemetil, especially during acute attacks.
Labyrinthitis: This inflammation of the inner ear can cause severe dizziness and nausea, which Stemetil helps to control.
Other Balance Problems: It is used to treat vertigo resulting from various other causes by acting as a vestibular sedative.

Addressing Psychiatric Conditions

As a first-generation antipsychotic, prochlorperazine is also used to treat certain mental health disorders.

Schizophrenia and Mania: It helps manage symptoms of psychotic illness, such as delusions and hallucinations, particularly in the chronic stage.
Short-Term Anxiety: For anxiety that has not responded to other treatments, Stemetil can be prescribed for a short duration, typically no longer than 12 weeks.

How Does Stemetil Work?

Stemetil's active ingredient, prochlorperazine, exerts its effects primarily by blocking dopamine receptors (specifically D2 receptors) in the brain. By doing so, it intercepts the signals that cause nausea and vomiting, which are often sent from the chemoreceptor trigger zone (CTZ) to the vomiting center in the brainstem. This blocking action also has sedative and anti-psychotic effects, which is why it's used for conditions like schizophrenia and anxiety.

Side Effects and Safety Precautions

Like all medications, Stemetil has potential side effects, and certain precautions must be taken to ensure safe use. It's especially important to be aware of dose-dependent and long-term side effects.

Common Side Effects

Drowsiness or sleepiness
Dizziness or feeling unsteady
Dry mouth
Blurred vision
Nasal congestion
Constipation
Restlessness and agitation

Serious Side Effects

Extrapyramidal Symptoms: This includes involuntary movements, muscle spasms (dystonia), tremors (pseudo-parkinsonism), and restlessness (akathisia), which are more likely with higher doses or long-term use.
Tardive Dyskinesia: A potentially irreversible condition involving involuntary facial and body movements. The risk increases with longer treatment, particularly in elderly women.
Neuroleptic Malignant Syndrome (NMS): A rare but potentially fatal reaction characterized by high fever, muscle stiffness, altered mental status, and irregular heartbeat.

Contraindications and Warnings

Stemetil is not suitable for everyone. It should not be used in:

Patients with a known hypersensitivity to prochlorperazine or other phenothiazines.
Individuals in a comatose state or with severe central nervous system depression.
Children under 2 years of age or weighing less than 10 kg.
Caution is needed in patients with liver disease, seizure disorders, or cardiovascular conditions.

Comparison: Stemetil vs. Other Antiemetics

Different anti-sickness medications work through various mechanisms, and a patient's response can vary. Here is a comparison of Stemetil with a common alternative, promethazine.


Feature	Stemetil (Prochlorperazine)	Promethazine
Mechanism of Action	Blocks dopamine (D2) receptors in the chemoreceptor trigger zone (CTZ).	Acts as a potent H1 antihistamine with anticholinergic and sedative properties.
Antiemetic Efficacy	Generally more effective and faster-acting for severe nausea and vomiting, especially in acute situations.	Effective, but potentially less potent for severe cases. Often used for milder sickness or motion sickness.
Sedation Levels	Causes some sedation, but studies suggest it may cause less sleepiness than promethazine.	Known for its strong sedative effects, often causing pronounced drowsiness.
Primary Uses	Severe nausea/vomiting, vertigo, inner ear disorders, schizophrenia, short-term anxiety.	Motion sickness, allergy symptoms, sleep aid, milder nausea.
Side Effect Profile	Risk of extrapyramidal symptoms (involuntary movements) and tardive dyskinesia, especially with long-term use.	High risk of drowsiness and anticholinergic effects like dry mouth and blurred vision.

Conclusion

Stemetil, with its active ingredient prochlorperazine, is a versatile and potent medication with well-established efficacy in managing severe nausea, vomiting, and vertigo. Its antiemetic properties are particularly valuable for conditions like chemotherapy side effects, post-operative sickness, and inner ear disorders such as Meniere's disease. It is also used in the treatment of psychotic disorders and short-term anxiety. While generally effective, users must be aware of its potential side effects, including the risk of neurological movement disorders with long-term use. Always consult a healthcare provider to determine the appropriate dosage and duration of treatment for your specific condition.

An authoritative resource for further information on prochlorperazine can be found at the National Health Service (NHS) website.

Frequently Asked Questions

Stemetil (prochlorperazine) typically starts to work within 30 to 60 minutes when taken orally. For inner ear conditions like Meniere's disease, it may take a few days to reach its full effect.

Common side effects include drowsiness, dizziness, blurred vision, a dry mouth, and constipation. It is important to avoid driving or operating machinery until you know how the medication affects you.

It is generally best to avoid drinking alcohol while taking Stemetil. Alcohol can intensify the medication's side effects, such as drowsiness and dizziness.

No, in most countries, Stemetil is a prescription-only medication. It should only be taken under the guidance of a healthcare professional.

Stemetil, a dopamine antagonist, is particularly effective for severe nausea and vertigo. It works differently from antihistamine-based antiemetics like promethazine, and studies suggest it may offer faster and more complete relief with less sedation in some cases.

Seek immediate medical attention if you experience signs of serious side effects, such as a high fever, severe muscle stiffness, uncontrolled muscle movements (especially of the face and neck), confusion, or an irregular heartbeat.

Long-term use of Stemetil is generally not recommended due to the increased risk of potentially irreversible movement disorders, such as tardive dyskinesia. For anxiety, for example, its use is often limited to a maximum of 12 weeks.

Stemetil is generally not recommended for children under 2 years of age or weighing less than 10 kg. In older children, the dosage is carefully managed by a doctor, especially for severe nausea and vomiting.