Phenothiazine (Antiemetic / Antivertigo) Pregnancy: Caution — use only if essential for severe nausea/vomiting

Prochlorperazine

Brand names: Stemetil, Buccastem (buccal)

Adult dose

Dose: Acute vertigo/nausea: 5–10 mg TDS oral. Severe/vomiting: 12.5 mg IM. Buccal (Buccastem): 3 mg BD dissolved between gum and upper lip.

Route: Oral, IM, or buccal

Frequency: TDS oral; single IM; BD buccal

Max: 40 mg/day oral

For acute vestibular disturbance, Ménière's acute attacks, and nausea. Limit duration to ≤2 weeks (risk of tardive dyskinesia with prolonged use). Avoid in elderly (fall risk, Parkinsonism risk).

Paediatric dose

Route: Oral or IM

Frequency: TDS

Max: 0.25 mg/kg per dose

Concentration: 5 mg tablet; 12.5 mg/mL IM mg/ml

Children: 0.25 mg/kg TDS. IM: 0.25 mg/kg per dose. Avoid in <10 kg. Risk of dystonic reactions in children (younger children more susceptible).

Dose adjustments

Renal

No dose adjustment required

Hepatic

Caution in hepatic impairment

Clinical pearls

Avoid in elderly: risk of falls, Parkinsonism, tardive dyskinesia; betahistine or anti-cholinergics preferred
Acute dystonic reactions in children: more common in children than adults — treat with procyclidine 5 mg IV or IM if occurs
Buccal route (Buccastem): useful when vomiting prevents oral drug absorption
Maximum 2-week course for vertigo — prolonged use causes tardive dyskinesia

Contraindications

Parkinson's disease
Bone marrow depression
Phaeochromocytoma

Side effects

Extrapyramidal effects (dystonia, akathisia, tardive dyskinesia with prolonged use)
QT prolongation
Drowsiness
Postural hypotension
Constipation

Interactions

Antihypertensives — additive hypotension
QT-prolonging drugs — additive QT risk
Anticholinergics — additive effects

Monitoring

Dystonic reactions
QTc
Blood pressure
Extrapyramidal symptoms

Reference: BNFc; BNF; BNF for Children. Verify against your local formulary and the latest BNF before prescribing.

Curated clinical cross-links plus same-class fallbacks.

Calculators

Pathways