Part of the Access Doctor nausea & vomiting guide.
Prochlorperazine (Stemetil) for Nausea & Vertigo: UK Prescription Guide
A UK-focused, clinically reviewed guide to prochlorperazine — how it works, Stemetil vs Buccastem, dosing, side effects, who should not take it, and how to get it without a GP appointment. All treatment information applies to UK-licensed medicines and NHS pathways.
When to get urgent help in the UK — call 999 or go to A&E straight away if you have:
- Vomiting blood, or vomit that looks like coffee grounds
- Green or bile-stained vomit, especially with severe abdominal pain or a swollen, tender tummy
- A sudden, severe headache, or headache with a stiff neck, fever, rash, or confusion
- New weakness, numbness, slurred speech, or loss of vision
- Chest pain, or vomiting after a head injury
- Signs of severe dehydration — confusion, very dark urine, no urine for 8–12 hours, or feeling faint on standing
For non-emergency advice in the UK, call NHS 111 or contact your GP. Ring 111 or your maternity unit if you are pregnant and cannot keep fluids down (possible hyperemesis gravidarum).
5–10mg
Standard oral or buccal dose for nausea and vertigo
Rx only
Stemetil tablets are prescription-only in the UK
D2 blocker
Dopamine antagonist — acts on the chemoreceptor trigger zone
Buccal
Dissolves between gum and cheek — useful when vomiting prevents swallowing
▶ Quick summary
Prochlorperazine is a prescription dopamine antagonist used in the UK to treat nausea, vomiting and vertigo. It works on the chemoreceptor trigger zone (CTZ) in the brain and is available as tablets, buccal tablets (Buccastem) and an injection. It is particularly useful for vertigo-related nausea, and for migraine attacks where vomiting makes swallowing a tablet impossible. UK pharmacy #9011198.
How Prochlorperazine Works
Prochlorperazine is an older-style medicine from the phenothiazine family. It works mainly by blocking dopamine D2 receptors in the chemoreceptor trigger zone (CTZ) — the part of the brain that samples your blood for signals that trigger nausea and passes them on to the vomiting centre. Blocking those receptors interrupts the signal and turns down the urge to be sick.
It also has antihistamine and anticholinergic effects, which help with vertigo-related nausea by calming signals coming from the balance system in the inner ear. That double action — damping down the CTZ and the vestibular system — is why prochlorperazine works across a wider range of nausea than medicines that only do one of the two.
Unlike domperidone, prochlorperazine does cross the blood–brain barrier. That is what makes it effective for vertigo and migraine nausea, but it also means it can cause central side effects such as drowsiness and movement problems that domperidone does not.
Tablets, Buccal Tablets, and Injection
| Form | Brand | Notes |
|---|---|---|
| Oral tablets | Stemetil 5mg | The most common form. Swallowed with water. First choice for most people at home. Prescription-only in the UK. |
| Buccal tablets | Buccastem M 3mg | Placed between the upper gum and cheek and left to dissolve slowly. Useful when nausea makes swallowing hard, or when you keep being sick. Available over the counter from UK pharmacies for migraine nausea. |
| Injection (IM) | Stemetil | Hospital or clinic use only, for severe acute vomiting. Not for self-administration. |
Buccastem M buccal tablets (3mg) can be bought from a UK pharmacy without a prescription, but only for nausea linked to migraine that has already been diagnosed by a doctor. For any other cause of nausea, or for the tablet form, you need a prescription.
What Is Prochlorperazine Used For?
- Vertigo-related nausea — including labyrinthitis, vestibular neuritis, BPPV (when nausea is the main problem), and Ménière’s disease. NICE CKS lists prochlorperazine as a first- or second-line option for acute vestibular nausea, alongside cyclizine.
- Migraine-associated nausea and vomiting — Buccastem is specifically licensed for this. Its buccal route gets around the absorption problems caused by migraine slowing the stomach down.
- Nausea and vomiting of central or metabolic origin — effective when the CTZ is the main pathway, for example in uraemia or drug-induced nausea.
- Post-operative nausea and vomiting (PONV) — used in hospital settings.
Not the right choice for: gastroenteritis or food poisoning (domperidone or metoclopramide suit gastric-pathway nausea better) · nausea in pregnancy (avoid phenothiazines unless specialist advice is given; cyclizine is first-line for nausea and vomiting of pregnancy) · motion sickness (cyclizine or hyoscine are preferred).
Dosing Guidance
| Form | Dose | Frequency | Notes |
|---|---|---|---|
| Stemetil tablets | 5mg | Up to three times daily | Take with or after food. Maximum 30mg in 24 hours. Prescription only. |
| Buccastem M buccal | 3mg (one tablet) | 1–2 times daily | Place between the upper gum and cheek. Do not chew, suck or swallow. Dissolves over 1–2 hours. |
Older adults: use the lowest dose that works and review regularly. Prochlorperazine increases the risk of falls, sedation, confusion and movement side effects in people over 65. The MHRA advises caution in older patients, particularly those with dementia, where antipsychotics are associated with a small increased risk of stroke.
Side Effects
Most people tolerate prochlorperazine well on short courses at standard doses. The most common effects are drowsiness and mild dizziness. The ones that matter more are:
- Extrapyramidal reactions — muscle stiffness, restlessness, tremor, or involuntary movements of the face, tongue or neck. These are more common in younger women and at higher doses. If they happen, stop the medicine and get medical advice the same day.
- Drowsiness — avoid driving or operating machinery until you know how it affects you.
- Low blood pressure on standing — dizziness when you get up, particularly in older patients and those already on blood-pressure medicines.
- Raised prolactin — relevant with long-term use, not with a short course.
- Anticholinergic effects — dry mouth, blurred vision, constipation, and difficulty passing urine. More likely in older adults, and worth flagging if you are already on other anticholinergic medicines.
Seek urgent help if you develop: severe muscle rigidity, a high temperature, a fast or irregular heartbeat, sweating, and confusion or drowsiness. This combination can be neuroleptic malignant syndrome — rare but serious, and it needs emergency hospital care. Stop the medicine and call 999 or go to A&E.
Driving and alcohol: prochlorperazine can cause drowsiness, blurred vision and dizziness, particularly with the first dose. Do not drive or operate machinery until you know how it affects you. Avoid alcohol while you are taking it — it adds to the sedation and can make low blood pressure worse.
Who Should Not Take Prochlorperazine
- Children under 10 years, unless under specialist supervision
- Pregnancy — especially the first trimester. Use only if other options have failed and under clinical guidance
- Parkinson’s disease — dopamine antagonists make motor symptoms worse
- History of bone marrow depression or blood disorders
- Severe heart disease, or a known long QT interval on an ECG
- Taking other medicines that prolong the QT interval — the combination raises the risk of dangerous heart rhythms
- Known allergy to phenothiazines
- Phaeochromocytoma or suspected bowel obstruction
Tell your prescriber or pharmacist about every medicine you take, including over-the-counter ones. Prochlorperazine interacts with a long list of common drugs, including some antidepressants, antipsychotics, heart medicines, Parkinson’s medicines, and strong painkillers. In the UK you can ask any pharmacist for a free medicines check.
Prochlorperazine vs Cyclizine for Vertigo Nausea
| Prochlorperazine | Cyclizine | |
|---|---|---|
| How it works | D2 antagonist plus anticholinergic | H1 antihistamine plus anticholinergic |
| Vertigo nausea | Yes — strong CTZ and vestibular action | Yes — dampens the vestibular system |
| Migraine nausea | Yes (Buccastem licensed) | Yes |
| Drowsiness | Moderate | Moderate |
| Pregnancy | Avoid if possible | First-line under RCOG guidance |
| Available without prescription | Buccastem M 3mg, for migraine only | Yes, 50mg tablets from a UK pharmacy |
| Movement side effects | Yes, especially at high doses or in younger women | No |
For a full guide to cyclizine — vertigo, motion sickness and pregnancy use: Cyclizine: complete UK guide →
Getting Prochlorperazine in the UK
Stemetil 5mg tablets need a prescription from a UK prescriber — your GP, a pharmacist independent prescriber, or another qualified clinician. If you are exempt from NHS prescription charges (for example, if you have a medical exemption certificate, are over 60, or are pregnant), you will not pay for an NHS prescription.
Buccastem M 3mg buccal tablets are different: they are a pharmacy (P) medicine in the UK, so you can buy them over the counter from a pharmacy without a prescription — but only for migraine-associated nausea, and only if a doctor has already diagnosed your migraine. For any other type of nausea, or if you need the tablet form, you will need a prescription.
Get prescription nausea treatment online
Access Doctor provides prescription antiemetics including prochlorperazine following an online consultation with a GPhC-registered pharmacist independent prescriber. UK-licensed medicines only. Discreet next-day delivery. GPhC pharmacy #9011198.
View nausea treatments →Frequently Asked Questions
What is prochlorperazine used for in the UK?
Prochlorperazine is used to treat nausea and vomiting caused by vertigo (such as labyrinthitis or vestibular neuritis), migraine, post-operative sickness, and nausea of central or metabolic origin. Buccastem M buccal tablets are specifically licensed for migraine-associated nausea and are available over the counter in UK pharmacies. Stemetil tablets require a prescription.
What is the difference between Stemetil and Buccastem?
Both contain prochlorperazine but differ in dose and route. Stemetil 5mg is an oral tablet taken with water, used across a range of nausea indications, and requires a prescription. Buccastem M 3mg is a buccal tablet that dissolves between the gum and cheek — useful when vomiting makes swallowing difficult — and is available over the counter in UK pharmacies specifically for migraine nausea.
Can I take prochlorperazine every day?
Short courses are appropriate for acute nausea, usually no more than a few days. Longer daily use increases the risk of extrapyramidal side effects, raised prolactin, and reliance on antiemetics. If you find yourself needing an antiemetic most days, see your GP to look at the underlying cause rather than continuing to treat the symptom.
Is prochlorperazine safe in pregnancy?
Prochlorperazine should generally be avoided in pregnancy, particularly in the first trimester. In the UK, cyclizine is the preferred first-line antiemetic for nausea and vomiting of pregnancy under RCOG guidance. If symptoms are severe and other options have failed, prochlorperazine should only be used under clinical supervision.
Can I drink alcohol with prochlorperazine?
It is best to avoid alcohol while taking prochlorperazine. Alcohol adds to the sedative effect, increases drowsiness and dizziness, and can worsen low blood pressure on standing. If you do drink, keep it to a minimum and do not drive.
Can I drive after taking prochlorperazine?
Prochlorperazine can cause drowsiness, blurred vision and dizziness, particularly with the first dose. Do not drive or operate machinery until you know how it affects you. If you feel drowsy or unsteady, do not drive.
Can I buy Buccastem M over the counter in the UK?
Yes. Buccastem M 3mg buccal tablets are a pharmacy (P) medicine in the UK. You can buy them from a pharmacy without a prescription for migraine-associated nausea, provided you have already been diagnosed with migraine by a doctor. For other causes of nausea, or for the tablet form (Stemetil), a prescription is needed.
References
- NICE CKS. Vertigo. Updated 2023. cks.nice.org.uk
- BNF. Prochlorperazine. bnf.nice.org.uk
- NHS. Prochlorperazine. nhs.uk/medicines/prochlorperazine
- RCOG. Management of nausea and vomiting of pregnancy and hyperemesis gravidarum. Green-top Guideline No. 69.
- MHRA. Yellow Card Scheme — reporting suspected side effects. yellowcard.mhra.gov.uk
Medical disclaimer: This article is for general information only and is not a substitute for personalised medical advice. Always speak to your GP or pharmacist before starting any treatment. In a medical emergency in the UK, call 999.
Yellow Card: If you suspect you have had a side effect from any medicine mentioned in this article, you can report it to the MHRA Yellow Card scheme at yellowcard.mhra.gov.uk. Reporting is voluntary and helps make UK medicines safer.