Critical Warnings And Restrictions (Safety First)

Basic Stemetil Information

• INN (International Nonproprietary Name): Prochlorperazine
• Brand Names Available In United Kingdom: Stemetil; Compazine (brand historically available); Various generics
• ATC Code: N05AB04
• Forms & Dosages: Tablets 5 mg and 10 mg (rarely 25 mg); Suppositories 25 mg; Injectable ampoules/vials 5 mg/mL and 12.5 mg/mL (IM/IV); Oral solution/syrup 5 mg/5 mL
• Manufacturers In United Kingdom: Heritage Pharmaceuticals; Teva; Sandoz; Fresenius Kabi; Medochemie
• Registration Status In United Kingdom: Registered as authorised medicines in major markets; prescription-only status across jurisdictions
• OTC / Rx Classification: Prescription Only (Rx)

High-Risk Groups (Elderly, Pregnancy, Chronic Illness)

Who should worry first? Older adults and people with certain neurological or organ conditions need close review before starting prochlorperazine.

Risk Factors

• Age 65 and over, especially with dementia or frailty.
• Diagnosed Parkinson’s disease.
• Severe liver impairment or significant renal dysfunction.
• Epilepsy or history of seizures.
• History of neuroleptic malignant syndrome or severe cardiovascular disease.
• Known hypersensitivity to phenothiazines.
• Children under 2 years or weight under 10 kg (oral) unless specialist advice obtained.

Key Warnings

Prochlorperazine carries increased risks in older adults, with higher mortality documented in dementia-related psychosis when antipsychotics are used.

Avoid routine high antipsychotic dosing in primary care; psychiatric indications need specialist oversight.

Monitoring Checklist

• Blood Pressure: baseline and post‑dose checks for hypotension, particularly after first doses.
• Sedation Score: observe for daytime somnolence and impairment of alertness.
• Extrapyramidal Symptoms (EPS): monitor for tremor, restlessness, acute dystonia.
• Seizure Activity: review history and monitor if on interacting medicines.
• Liver/Kidney Function: review baseline and adjust dose if impairment present.

Interaction With Activities (Driving, Workplace Safety Under UK Law)

Will this medicine affect everyday tasks like driving or using tools?

Yes — prochlorperazine commonly causes sedation, dizziness and blurred vision which may reduce ability to drive or work safely.

Fitness-To-Drive Checklist

• Do you feel drowsy or dizzy after taking the medicine?
• Is your vision blurred or double?
• Are you performing safety‑critical duties (driving, machine operation)?
• If yes to any, do not drive and discuss alternatives with your prescriber or pharmacist.

Pharmacist Counselling Prompts

• Ask about driving, shift work and use of heavy machinery before supply.
• Advise patients to check DVLA guidance on medicines and driving.
• Document the driving advice given in the patient notes.

Q&A — “Can I Drive After Taking It In The UK?”

Q: Will prochlorperazine affect my ability to drive?

A: It can.

A: Sedation, dizziness and blurred vision are common.

A: If you feel impaired, do not drive; discuss alternatives with your prescriber or pharmacist.

A: Always follow DVLA guidance and workplace safety policies.

Usage Basics

INN, Brand Names Available In The UK

What is the active ingredient and which brands might you see in a UK prescription?

INN

Prochlorperazine

Brand Names

Stemetil is commonly used in the UK and Europe; Compazine is a historical brand; many generics are available.

Buccal Formulation

Buccastem is a related buccal prochlorperazine preparation sometimes used for rapid antiemetic effect.

Typical brand and form availability includes tablets (5 mg, sometimes 10 mg), injectable ampoules for hospital use and suppositories for patients unable to take oral medication.

Legal Classification (POM, P, GSL)

How can patients legally obtain prochlorperazine in the UK?

• NHS Prescription: available when clinically indicated and prescribed by a GP or hospital clinician.
• Private Prescription: issued by private clinics or prescribers and dispensed by community pharmacies.
• Hospital Supply: injectable ampoules and acute care doses are supplied in A&E and wards.

There is no general sale list availability; prochlorperazine is prescription-only in major jurisdictions.

Dosing Guide

Standard Regimens (NHS Guidance)

What doses are commonly used for adults?

Duration Checklist

• Nausea: aim for short courses under seven days where practical.
• Psychiatric Use: review response and adverse effects at two to four weeks; maintain only under specialist monitoring if continued.

Adjustments For Comorbidities

How should dosing change with age or comorbidity?

• Reduce dose in elderly patients; start at the lowest effective dose and review frequently.
• Reduce and monitor in hepatic or renal impairment because clearance may be reduced.
• Avoid or use extreme caution in Parkinson’s disease — prochlorperazine can worsen movement symptoms.
• In epilepsy, use caution because prochlorperazine may lower the seizure threshold.

Paediatric Note: Specialist paediatric dosing applies; an example for older children is about 0.13 mg/kg every six to eight hours for vomiting, but always check the SPC and paediatric guidance before prescribing.

Boxed Note: Consult the SPC and MHRA guidance for all paediatric dosing.

Q&A — “What If I Miss A Dose?”

Q: Missed dose advice for prochlorperazine?

A: Take as soon as remembered unless it is nearly time for the next dose.

A: Do not double up to make up for a missed dose.

A: For severe vomiting where parenteral dosing is planned, seek clinical advice if timings are uncertain.

Interaction Chart

Food And Drinks (Alcohol, Tea/Coffee, Diet Habits)

Are there food or drink choices that change how the medicine works?

• Avoid alcohol because it potentiates sedation and may increase hypotension risk.
• Caffeine (tea/coffee) can mask sleepiness but does not prevent other adverse effects.
• No major food interactions identified, but gastric emptying and oral absorption can vary with diet and formulation.

Pharmacist Counselling Checklist

• Advise patients to avoid alcohol while taking prochlorperazine.
• Discuss caffeine use if patients report persistent sedation.
• Explain which formulation they have (tablet, buccal, injectable) and how that affects onset.

Common Drug Conflicts (MHRA Yellow Card Data)

Which medicines interact significantly with prochlorperazine, and what should be done?

User Reports & Trends

What do patients commonly say about taking prochlorperazine?

• Many report rapid relief of acute nausea and vomiting when the correct formulation is used.
• Drowsiness and tiredness are commonly reported, especially at higher doses or when taken with other sedatives.
• Extrapyramidal symptoms such as akathisia (restlessness) or acute dystonia are described more frequently with repeated dosing or higher doses.
• Mixed reports exist for migraine-associated nausea; some patients find good benefit, others prefer alternatives.
• Some patients prefer ondansetron for chemotherapy or post‑operative nausea for tolerability, but prochlorperazine remains used for cost and availability reasons in NHS settings.

Safety Note: Patients should be encouraged to report adverse reactions via the MHRA Yellow Card scheme.

Access & Purchase Options

Boots, LloydsPharmacy, Superdrug

How do patients typically obtain prochlorperazine from high‑street pharmacies?

• GP prescription presented at community pharmacy for dispensing.
• Urgent care or A&E may supply injectable forms for acute treatment.
• Private prescriptions can be presented to the same chains for private dispensing.

Typical patient pathway: GP consultation → Prescription issued → Pharmacy dispensing and counselling.

Online Pharmacies And NHS E‑Prescriptions

Can the medicine be organised remotely?

• NHS e‑prescriptions and electronic repeat dispensing make remote collection straightforward where clinically appropriate.
• Registered online pharmacies in the UK can dispense on receipt of a valid prescription and provide remote counselling.
• Warning: avoid unregulated international vendors due to risk of counterfeit packs or incorrect formulation and strength.

Safe Online Purchase Checklist:

• MHRA‑registered pharmacy and visible pharmacy logo.
• Valid prescription required before dispatch.
• Clear patient information leaflet and contact details for clinical questions.

In our online pharmacy, stemetil is available without a prescription, with discreet delivery to United Kingdom in 5-14 days.

Mechanism & Pharmacology

Simplified Explanation

How does prochlorperazine work to stop nausea?

Mechanism

Prochlorperazine is a phenothiazine dopamine D2 receptor antagonist (ATC N05AB04).

Antiemetic Effect

Blockade of dopamine receptors in the chemoreceptor trigger zone reduces nausea and vomiting.

Onset By Formulation

Injectable forms act fastest; buccal/suppository routes give intermediate onset; oral tablets are slower.

Clinical Terms

What should clinicians monitor based on pharmacology?

Pharmacokinetics: hepatic metabolism with reduced clearance in liver impairment; half‑life varies with dose and formulation.

Indications & Off‑Label Uses

MHRA‑Approved Uses

• Licensed for severe nausea and vomiting.
• Licensed product indications include short‑term treatment of non‑psychotic anxiety in some formulations.
• Used in hospital settings by IM/IV route for acute severe vomiting.

Off‑Label Practices In NHS And Private Care

Where is prochlorperazine used beyond the SPC?

• Migraine‑associated nausea where clinicians judge benefit outweighs risk.
• Palliative care antiemesis as part of multi‑modal symptom control.
• Acute vertigo management in some settings.

Off‑Label Prescribing Checklist

• Document the clinical rationale for off‑label use.
• Discuss risks and benefits with the patient or carer and obtain informed consent.
• Record monitoring and follow‑up plan in the notes.

Key Clinical Findings (UK/EU Studies 2022–2025)

What have recent UK and EU reviews said about prochlorperazine?

Recent reviews reaffirm its efficacy as an inexpensive antiemetic in acute care settings, especially where ondansetron is not available or cost‑prohibitive.

Comparisons with ondansetron and metoclopramide show that ondansetron often has better tolerability for chemotherapy and postoperative nausea but carries higher acquisition costs.

Safety signals continue to document extrapyramidal reactions and the need for caution in elderly people with dementia.

Clinicians should consult MHRA drug safety updates and local formularies for the latest guidance and any new regulator communications.

Alternatives Matrix

NHS Prescribing Alternatives (Comparison Table)

Pros And Cons Checklist

• Consider efficacy for the indication (gastrointestinal stasis, chemo, post‑op).
• Assess side‑effect risk: EPS, sedation, cardiovascular.
• Review patient comorbidities: cardiac, neurological, hepatic.
• Check potential drug interactions before prescribing.
• Consider cost and NHS formulary status for routine use.

Common Questions (Patient‑Facing FAQs)

• Will it make me sleepy? — Yes, drowsiness and sedation are common; avoid driving if affected.
• How quickly does it work? — Injectable forms act fastest; buccal and suppository give intermediate onset; tablets are slower.
• Can it cause movement problems? — Yes; tremor, restlessness and dystonia can occur, particularly at higher doses or with repeated dosing.
• Is it safe in pregnancy? — Pregnancy use requires specialist obstetric advice; avoid unless clearly necessary and discussed with a clinician.
• What should I do if I experience severe side effects? — Seek urgent medical attention for severe EPS, high fever, breathing difficulty or fainting.
• How do I report a side effect? — Use the MHRA Yellow Card scheme to report suspected adverse reactions.

NHS Cost & Access Comparison Table

Checklist For Prescription Exemptions: age under 16 (or under 19 in full‑time education), pregnancy or maternity certificates, certain benefits and low income schemes.

Safety Note: Verify the current NHS prescription charge before publication as rates change.

Registration & Regulation

MHRA Approval Process

Which documents should clinicians check before prescribing?

• Summary of Product Characteristics (SPC) for the specific licensed product.
• British National Formulary (BNF) entries for dosing and interactions.
• MHRA safety updates and communications for any new warnings.

NHS Prescribing Framework

What are the prescribing rules in the NHS?

• Prochlorperazine is prescription‑only and must be prescribed for an appropriate clinical indication.
• Document rationale and monitoring for any off‑label use.
• Follow local trust formularies and electronic prescribing systems (EPS) when applicable.

Prescriber Checklist: confirm indication, select dose and route, arrange monitoring and provide patient information.

Storage & Handling

UK Household Storage (Cold/Damp Climate)

How should patients store their tablets, especially in damp UK homes?

• Store at room temperature, ideally 15–30°C.
• Protect tablets from excessive moisture and light; keep in original blister packs.
• Avoid storing medicines in bathrooms or near sinks where humidity is high.
• Injectable forms require manufacturer guidance and should only be handled by trained personnel.

Pharmacy or GP services should be used to dispose of unused injectables and controlled‑waste items safely.

Guidance From NHS And Pharmacists

• Provide a printed patient information leaflet with each supply.
• Advise patients travelling abroad to carry a copy of the prescription and store medicines in temperature‑controlled luggage.
• Recommend pharmacy drop‑off for expired or unwanted medicines.

Guidelines For Proper Use (Patient Safety & Pharmacist Counselling)

UK Pharmacist Counselling Style

What should the pharmacist say at the point of supply?

Standard Counselling Script:

• Confirm the indication and the exact formulation supplied (tablet, buccal, suppository, injection).
• Explain dosing and timing, and how long to expect to take it for the current problem.
• Describe common side effects to expect: drowsiness, dry mouth, constipation and possible EPS.
• Advise on interactions including alcohol and other CNS depressants.
• Give clear driving and workplace safety advice and document that advice in the record.
• Explain when to seek urgent care: severe EPS, high fever, breathing difficulty, collapse or signs of infection.

Red‑Flag Symptoms Checklist

• Acute dystonia (sustained muscle spasm, particularly of the neck or eyes).
• Marked restlessness or inability to sit still.
• High fever and muscle rigidity (possible neuroleptic malignant syndrome).
• Severe shortness of breath, fainting or collapse.

EPS

Movement disorders including tremor, dystonia and akathisia.

NMS

Neuroleptic malignant syndrome — rare, life‑threatening reaction with fever and rigidity.

NHS Patient Safety Advice

• Keep an up‑to‑date medicines list and inform all prescribers of current medications.
• Report adverse reactions via the MHRA Yellow Card scheme.
• Attend review appointments for repeated or long‑term use; children and elderly require specialist dosing and monitoring.
• Follow‑Up Timings: contact within 48–72 hours for acute reaction advice; two to four weeks review for psychiatric indications.

Delivery Across United Kingdom

Final Notes And Practical Tips

Short patient story: a patient with a migraine arrives at a Friday evening clinic with persistent vomiting and cannot keep oral tablets down.

TheER team gives IM prochlorperazine and arranges a prescription for oral tablets for review the following week.

This example shows how choice of formulation matters and why clear follow‑up is essential.

Remember to consult the SPC and BNF for product‑specific instructions, check for interactions and document all advice given at supply.