Compazine (Prochlorperazine) Indications
Compazine (prochlorperazine) is indicated for the management of nausea and vomiting across multiple clinical settings, including chemotherapy-induced nausea and vomiting (CINV), radiation-induced nausea and vomiting (RINV), postoperative nausea, and palliative care settings.
Primary Indications
Chemotherapy-Induced Nausea and Vomiting (CINV)
Prochlorperazine is recommended for breakthrough or refractory CINV when first-line antiemetics (5-HT3 antagonists and corticosteroids) fail to control symptoms 1.
For low to moderate emetogenic risk chemotherapy, prochlorperazine 10 mg orally or IV can be used as prophylaxis, with optional dexamethasone 20 mg 1.
The typical dosing is 10-20 mg orally or IV, administered 3-4 times daily as needed for breakthrough nausea 1.
Prochlorperazine works through dopaminergic pathway antagonism in the chemoreceptor trigger zone, making it effective when serotonin antagonists alone are insufficient 1.
Radiation-Induced Nausea and Vomiting (RINV)
For low emetic risk radiation therapy, prochlorperazine 10 mg oral or IV can be used either as rescue therapy or prophylactically 1.
If rescue therapy is required during radiation treatment, prophylactic antiemetics should continue throughout the entire radiation course 1.
Prochlorperazine is listed as an acceptable dopamine receptor antagonist option alongside metoclopramide for minimal to low-risk RINV 1.
Palliative Care and End-of-Life Settings
Prochlorperazine 5-10 mg administered 3-4 times daily (oral, IV, or subcutaneous routes) is recommended for managing nausea in palliative care patients 1.
It is specifically indicated for nausea and vomiting due to bowel obstruction when used alongside other agents targeting dopaminergic pathways 1.
In terminally ill patients with inoperable bowel obstruction, prochlorperazine can be combined with chlorpromazine and opioids for comprehensive symptom management 1.
Postoperative Nausea and Vomiting
Prochlorperazine is recommended for postoperative nausea management in surgical patients, particularly those not amenable to further interventions 1.
It should be part of a multimodal approach targeting multiple receptor pathways for optimal symptom control 1.
Opioid-Induced Nausea
Prochlorperazine is an effective first-line agent for opioid-induced nausea, administered as 10 mg orally every 6 hours as needed 1.
If nausea persists despite as-needed dosing, administer around-the-clock for one week, then adjust based on response 1.
Prochlorperazine can be combined with other antiemetics targeting different mechanisms (such as ondansetron) for synergistic effect when monotherapy fails 1.
Dosing Specifications
Standard Adult Dosing
Oral/IV: 5-10 mg administered 3-4 times daily for most indications 1.
Pretreatment dosing: 10 mg orally given before chemotherapy, with additional doses every 6 hours as needed 1.
Rectal suppositories: 25 mg every 12 hours can be used when oral/IV routes are not feasible 1.
Route-Specific Considerations
Intravenous administration (2.5-5 mg by slow IV push) provides rapid onset, with mean time to cessation of vomiting of 8.5 minutes versus 35 minutes for intramuscular administration 2.
Oral and IV routes demonstrate similar efficacy when gastrointestinal absorption is intact 3.
Critical Safety Considerations and Contraindications
Extrapyramidal Symptoms (EPS) Risk
The incidence of extrapyramidal symptoms with prochlorperazine is approximately 14% in cancer patients, significantly higher than alternative agents like perospirone (0%) 4.
Akathisia is the most common EPS manifestation, typically occurring within the first week of treatment 4.
EPS risk is dose-dependent and increases with prolonged use, making short-term use preferable whenever possible 5, 6.
Pediatric Safety Concerns
In children, EPS occurs in 9% with single doses (95% CI 3-29%) and 4% with multiple doses (95% CI 1-11%) 6.
Sedation affects 10% of children (95% CI 5-21%) receiving multiple doses 6.
Rare but serious adverse events including seizures, neuroleptic malignant syndrome, and fatalities have been reported in pediatric populations, warranting extreme caution 6.
Absolute Contraindications
Avoid in patients with seizure disorders or pheochromocytoma 7, 3.
Do not use in patients with GI bleeding or mechanical bowel obstruction 7, 3.
Caution is required in patients with severe renal or hepatic impairment, requiring dose adjustment 3.
Comparative Efficacy
Prochlorperazine demonstrates equivalent efficacy to delta-9-THC for CINV across wide-ranging chemotherapy regimens, with 75% of patients showing response 8.
Studies have not shown newer 5-HT3 medications to be superior to older dopaminergic agents like prochlorperazine for treating nausea at end of life 1.
When compared to metoclopramide, both agents are effective dopamine antagonists, though metoclopramide has additional prokinetic properties that may be advantageous in certain settings 7.
Clinical Pitfalls to Avoid
Do not overlook akathisia, which can be mistaken for anxiety or agitation rather than recognized as a drug-induced movement disorder 4.
Avoid prolonged use beyond what is necessary to minimize tardive dyskinesia risk, which has been documented with long-term prochlorperazine therapy 5.
Monitor for hypotension with IV administration, though this is rare when given as a slow push over one minute 2.
Consider alternative antiemetics (ondansetron, granisetron, or atypical antipsychotics like perospirone) in patients at high risk for movement disorders 5, 4.