Stemitil

# Stemitil ## Overview - **Classification**: Phenothiazine derivative, antiemetic, antipsychotic. - **Mechanism**: Blocks D1 and D2 dopamine receptors in the chemoreceptor trigger zone (CTZ) and elsewhere. Also has anticholinergic, antihistamine, and alpha-adrenergic blocking effects. ## Primary Indications 1. **Severe Nausea and Vomiting** - For control of severe nausea and vomiting. 2. **Migraine Headache** - Adjunct for acute migraine treatment. 3. **Vertigo** - Symptomatic relief of vertigo associated with Ménière's disease. ## Adult Dosing ### Standard Dosing **Severe Nausea and Vomiting** - **Oral**: - **Dose**: **5-10 mg** - **Frequency**: 3-4 times daily - **Route**: Oral - **IM**: - **Dose**: **5-10 mg** - **Frequency**: Every 3-4 hours as needed - **Route**: Intramuscular (IM) - **Max**: **40 mg/day** - **IV**: - **Dose**: **2.5-10 mg** - **Frequency**: Slow IV push over 2-5 minutes, may repeat in 30 min. - **Route**: Intravenous (IV) - **Max**: **10 mg/dose**, **40 mg/day** (usually for short-term acute use) - **Rectal**: - **Dose**: **25 mg** - **Frequency**: Twice daily - **Route**: Rectal suppository **Acute Migraine Headache** - **Oral**: - **Dose**: **10 mg** - **Frequency**: 3-4 times daily - **Route**: Oral - **IM/IV (Acute Treatment)**: - **Dose**: **10 mg** IM or slow IV (over 2-5 minutes) - **Frequency**: Single dose; IV can repeat once if needed - **Route**: IM or IV - **Max**: **30-40 mg/day** total ### Dose Adjustments - **Renal Impairment**: No specific dose adjustment for mild-moderate. Use with caution in severe impairment. - **Hepatic Impairment**: Use with caution. Consider reduced doses and monitor for adverse effects. - **Elderly Patients**: Start with lower doses (**2.5-5 mg**) due to increased sensitivity to side effects. Higher risk of EPS and orthostatic hypotension. ## Pediatric Dosing ### Neonates (0-28 days) - **Contraindicated**: Due to high risk of extrapyramidal symptoms (EPS) and other severe adverse effects. ### Infants (1-12 months) - **Contraindicated**: Not recommended due to significant risk of severe adverse effects. Limited safety data. ### Children (1-12 years) **Nausea and Vomiting (Severe)** - **Age/Weight Restrictions**: Not recommended for children < 2 years or < 9 kg. - **Oral/Rectal**: - **Dose**: **0.4 mg/kg/day** - **Frequency**: Divided into 3-4 doses per day - **Max**: **10 mg/dose** or **25 mg/day** (oral/rectal) - **Route**: Oral, Rectal - **IM**: - **Dose**: **0.13 mg/kg/dose** - **Frequency**: Once, can repeat after 4 hours if needed - **Max**: **10 mg/day** (IM) - **Route**: Intramuscular (IM) - **Special Notes**: Monitor closely for EPS. Avoid in dehydrated children. ### Adolescents (13-18 years) - **Dose**: Generally follow adult dosing recommendations. - **Maximum**: Adult maximum doses apply. - **Special Notes**: Start at the lower end of the adult dose range and titrate carefully. ## Safety Information ### Contraindications - **Absolute**: Hypersensitivity to prochlorperazine or other phenothiazines. - **Absolute**: Comatose states, severe CNS depression. - **Absolute**: Bone marrow depression, blood dyscrasias. - **Absolute**: Children < 2 years or < 9 kg. - **Relative**: Angle-closure glaucoma, prostatic hypertrophy, severe cardiovascular disease. ### Common Adverse Effects - **Very Common (>10%)**: Sedation/drowsiness, dizziness. - **Common (1-10%)**: Dry mouth, blurred vision, constipation, orthostatic hypotension, extrapyramidal symptoms (EPS - dystonia, akathisia, parkinsonism), restlessness. - **Serious but Rare**: Neuroleptic Malignant Syndrome (NMS), agranulocytosis, tardive dyskinesia, seizures, severe cardiac arrhythmias (QT prolongation). ### Key Drug Interactions - **CNS Depressants (opioids, benzodiazepines, alcohol)**: Potentiates sedation; increased risk of respiratory depression. - **Anticholinergic Drugs**: Additive anticholinergic effects (e.g., dry mouth, urinary retention). - **Dopamine Agonists (e.g., levodopa)**: Prochlorperazine blocks dopamine receptors, reducing their efficacy. - **QT-prolonging Drugs**: Increased risk of ventricular arrhythmias; use with caution. ## Monitoring & Follow-up - **Before Treatment**: Assess for contraindications, history of EPS or NMS. - **During Treatment**: Monitor for orthostatic hypotension, EPS (especially early), sedation, anticholinergic effects. - **Clinical Signs**: Watch for involuntary movements, muscle rigidity, fever, altered mental status (NMS). ## Clinical Pearls - 💡 **Tip 1**: Administer IV doses slowly (over 2-5 minutes) to minimize the risk of hypotension and EPS. - 💡 **Tip 2**: Consider co-administering with diphenhydramine or benztropine (IM/IV) to prevent/treat acute EPS. - 💡 **Tip 3**: Counsel patients about potential sedation and dizziness; advise against driving until effects are known. - 💡 **Tip 4**: Advise patients to change positions slowly to minimize orthostatic hypotension. > **⚠️ Important**: This information is for educational purposes only. Always consult current prescribing information, local guidelines, and clinical judgment before prescribing.