Recommended Dosage of Prochlorperazine (Stemitil)
For adults with nausea and vomiting, the recommended dose of prochlorperazine is 5-10 mg orally 3-4 times daily, with a maximum daily dose of 40 mg. 1
Adult Dosing Guidelines
For Nausea and Vomiting:
- Oral tablets: 5-10 mg 3-4 times daily 1
- Daily dosages above 40 mg should only be used in resistant cases 1
- For breakthrough therapy in radiation-induced nausea: 5-10 mg orally or IV 2
For Psychiatric Disorders:
- Non-psychotic anxiety: 5 mg 3-4 times daily (not to exceed 20 mg per day or longer than 12 weeks) 1
- Psychotic disorders including schizophrenia:
Pediatric Dosing
Prochlorperazine should not be used in:
- Children under 20 pounds in weight 1
- Children under 2 years of age 1
- Conditions for which children's dosages have not been established 1
For severe nausea and vomiting in children, weight-based dosing applies:
- 20-29 lbs: 2.5 mg 1-2 times daily (max: 7.5 mg/day) 1
- 30-39 lbs: 2.5 mg 2-3 times daily (max: 10 mg/day) 1
- 40-85 lbs: 2.5 mg 3 times daily or 5 mg 2 times daily (max: 15 mg/day) 1
Special Considerations
Elderly Patients:
- Use lower dosage ranges for most elderly patients 1
- Increase dosage more gradually due to increased susceptibility to hypotension and neuromuscular reactions 1
- Monitor response carefully and adjust dosage accordingly 1
Debilitated or Emaciated Patients:
- Increase dosage more gradually 1
Side Effects and Precautions
- Extrapyramidal symptoms (EPS) are a significant concern, particularly in children who seem more prone to develop these reactions even on moderate doses 3
- In a study of cancer patients receiving prochlorperazine as an antiemetic with opioids, 14% developed akathisia (a type of EPS) within one week 4
- QT interval prolongation is possible with repeated doses, which could potentially precipitate torsades de pointes 5
- Concomitant use with dofetilide is contraindicated due to potential QT prolongation 2
- Sedation is a common side effect, with one study showing significantly fewer complaints of sleepiness with prochlorperazine compared to promethazine (38% vs 71%) 6
Efficacy
- In a randomized, double-blind clinical trial comparing prochlorperazine to promethazine for nausea and vomiting in emergency departments, prochlorperazine worked significantly better and faster with fewer treatment failures (9.5% vs 31%) 6
- A recent study in Indian patients found prochlorperazine at a mean dose of 14.9 mg/day was well-tolerated and effective for acute dizziness, with only 0.006% of patients reporting adverse drug reactions 7
Combination Therapy
- For persistent nausea despite prochlorperazine, consider adding a serotonin antagonist such as ondansetron or granisetron 5
- For chemotherapy-induced nausea, a combination approach with dexamethasone may be more effective 5
Remember to monitor patients closely for extrapyramidal symptoms, particularly akathisia, which can occur early in treatment. For patients experiencing these side effects, prompt discontinuation of the medication and appropriate treatment may be necessary.