Stemetil 12.5 mg/ml Injection

Phenothiazine antiemetic for:

• Severe nausea and vomiting (including migraine-related)
• Vertigo and dizziness from Ménière's disease, labyrinthitis
• Short-term treatment of anxiety; schizophrenia (higher doses, specialist)

Nausea/vomiting (adults): 5–10 mg two to three times daily; acute: 20 mg then 10 mg after 2 hours.

Vertigo: 5 mg three times daily, increased to max 30 mg/day; reduce gradually.

Buccal tablets 3 mg: 1–2 tablets twice daily placed between gum and upper lip.

Injection: 12.5 mg deep IM, then oral after 6 hours.

Children: over 10 kg (usually 1 year+) — 250 microgram/kg two to three times daily only for severe vomiting of known cause; avoid in young children.

• Use the shortest course possible.

• Children under 10 kg / under 1 year
• Reduced consciousness, CNS depression
• Bone marrow depression, phaeochromocytoma
• Allergy to phenothiazines

Common: drowsiness, dizziness, dry mouth, blurred vision, constipation.

Less common: acute dystonia (involuntary muscle spasms of face/neck/eyes — more in young people and children), restlessness (akathisia), parkinsonism, low blood pressure.

Rare but serious: tardive dyskinesia (long use), neuroleptic malignant syndrome (fever, rigidity, confusion), QT prolongation, jaundice, low white cells, skin photosensitivity.

• May cause drowsiness — avoid driving and alcohol.
• Elderly (falls, low BP; increased stroke/death risk in dementia), Parkinson's disease, epilepsy, prostate enlargement, glaucoma, heart disease: caution.
• Avoid strong sunlight.
• Stop and seek help for muscle spasms or high fever with stiffness.

Avoid unless needed (newborn movement and withdrawal symptoms if used late in pregnancy). Avoid while breastfeeding where possible.

• Alcohol, sedatives, opioids, antihistamines (more drowsiness)
• Other QT-prolonging drugs (arrhythmia)
• Anticholinergics (more side effects); levodopa (opposing effects)
• Antihypertensives (low BP); lithium (neurotoxicity)

Drowsiness, low blood pressure, movement disorders, seizures, arrhythmias, low temperature. Emergency care.

Store below 30°C, protected from light.