II. Indications

  1. Psychosis (Schizophrenia, Mania)
  2. Intractable Hiccups
  3. Nausea or Vomiting
  4. Acute Intermittent Porphyria
  5. Tetanus

III. Mechanism

  1. Phenothiazine released in the early 1950s and among the first Antipsychotic agents
  2. Low potency Dopamine D2 receptor Antagonist (Antipsychotic effect)
  3. Also blocks Histamine H1 and muscarinic M1 receptors (Antiemetic effect)

IV. Dosing: Schizophrenia, Mania or other acute Psychosis

  1. Adult Oral Dosing
    1. Start: 25 mg orally three times daily
    2. Titrate to 400 mg/day in divided doses
      1. May increase dose 20 to 50 mg/day every few days in severe cases
    3. Target: 200 to 500 mg/day in most cases (800-1000 mg/day may be needed in some severe cases)
    4. Maximum: 1000 mg/day in divided doses
  2. Adult IM Dosing (hospitalized patients)
    1. Start 24 mg IM
    2. May repeat 25 to 50 mg IM in next hour
    3. May increase dose as needed over days to maximum of 400 mg every 4 to 6 hours

V. Dosing: Adult Miscellaneous

  1. Intractable Hiccups
    1. Oral: 25 to 50 mg orally every 6 to 8 hours as needed
    2. IM: 25 to 50 mg IM (if refractory to oral dosing)
    3. Infusion: 25 to 50 mg in 500 to 1000 ml NS slow IV infusion (if refractory to IM dosing)
  2. Presurgical Apprehension
    1. Oral: 25 to 50 mg orally 2 to 3 hours before procedure
    2. IM: 12.5 to 25 mg IM 1 to 2 hours before procedure
  3. Nausea or Vomiting
    1. Avoid in hypotensive patients
    2. Oral: 10 to 25 mg orally every 4 to 6 hours as needed
      1. May increase to 25 to 50 mg every 3 to 4 hours as needed
    3. IM: 12.5 mg IM for perioperative Nausea, Vomiting
      1. May repeat 12.5 mg IM dose at 30 minutes if not hypotensive
    4. IV: 2 mg IV injected over 2 minutes (no faster than 1 mg/min) every 2-3 minutes as needed
      1. Cummulative maximum: 25 mg
      2. Use a diluted solution of Chlorpromazine 1 mg/ml
  4. Acute Intermittent Porphyria
    1. Oral: 25 to 50 mg orally every 6 to 8 hours as needed
    2. IM: 25 mg IM every 6 to 8 hours as needed (if patient unable to take oral doses)
  5. Tetanus
    1. IM: 25 to 50 mg IM every 6 to 8 hours
    2. Infusion: 25 to 50 mg in 500 to 1000 ml NS slow IV infusion (no faster than 1 mg/ml)

VI. Dosing: Children

  1. Indications
    1. Psychosis or severe behavioral disorder
    2. Nausea or Vomiting
  2. Dosing (age 6 months to 12 years)
    1. Oral: 0.55 mg/kg orally every 4 to 6 hours
    2. IM: 0.55 mg/kg IM every 6 to 8 hours
      1. Maximum IM dose up to age 5 years (23 kg): 40 mg/day
      2. Maximum IM dose up to age 5 to 12 years (23 to 46 kg): 75 mg/day

VIII. Drug Interactions

  1. Potentiates Central Nervous System Depressants (e.g. Alcohol, Opioids) with apnea risk
  2. Metabolized by CYPA12, CYP2D6 and CYP3A4

IX. Safety

  1. Unknown safety in pregnancy (but may be Teratogenic in animal studies)
  2. Avoid in Lactation

X. Resources

  1. Chlorpromazine (DailyMed)
    1. https://dailymed.nlm.nih.gov/dailymed/drugInfo.cfm?setid=aa086a21-de85-4b03-af58-49b70acf8cf0
  2. Chlorpromazine (Stat Pearls)
    1. Mann (2022) Chlorpromazine, StatPearls, Treasure Island
      1. https://www.ncbi.nlm.nih.gov/books/NBK553079/

XI. References

  1. (2016) Med Lett Drugs Ther 58(1510): 160-5
  2. Olson (2020) Clinical Pharmacology, Medmaster Miami, p. 42-3
  3. Hamilton (2020) Tarascon Pocket Pharmacopoeia

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Related Studies

Cost: Medications

chlorpromazine (on 12/21/2022 at Medicaid.Gov Survey of pharmacy drug pricing)
CHLORPROMAZINE 10 MG TABLET Generic $1.14 each
CHLORPROMAZINE 100 MG TABLET Generic $1.16 each
CHLORPROMAZINE 200 MG TABLET Generic $2.34 each
CHLORPROMAZINE 25 MG TABLET Generic $0.56 each
CHLORPROMAZINE 50 MG TABLET Generic $1.09 each

Ontology: Chlorpromazine (C0008286)

Definition (NCI) A phenothiazine and traditional antipsychotic agent with anti-emetic activity. Chlorpromazine exerts its antipsychotic effect by blocking postsynaptic dopamine receptors in cortical and limbic areas of the brain, thereby preventing the excess of dopamine in the brain. This leads to a reduction in psychotic symptoms, such as hallucinations and delusions. Chlorpromazine appears to exert its anti-emetic activity by blocking the dopamine receptors in the chemical trigger zone (CTZ) in the brain, thereby relieving nausea and vomiting.
Definition (MSH) The prototypical phenothiazine antipsychotic drug. Like the other drugs in this class chlorpromazine's antipsychotic actions are thought to be due to long-term adaptation by the brain to blocking DOPAMINE RECEPTORS. Chlorpromazine has several other actions and therapeutic uses, including as an antiemetic and in the treatment of intractable hiccup.
Definition (CSP) prototypical phenothiazine antipsychotic drug; antipsychotic actions are thought to be due to long-term adaptation by the brain to blocking dopamine receptors; chlorpromazine has several other actions and therapeutic uses, including as an antiemetic and in the treatment of intractable hiccup.
Definition (PDQ) A phenothiazine and traditional antipsychotic agent with anti-emetic activity. Chlorpromazine exerts its antipsychotic effect by blocking postsynaptic dopamine receptors in cortical and limbic areas of the brain, thereby preventing the excess of dopamine in the brain. This leads to a reduction in psychotic symptoms, such as hallucinations and delusions. Chlorpromazine appears to exert its anti-emetic activity by blocking the dopamine receptors in the chemical trigger zone (CTZ) in the brain, thereby relieving nausea and vomiting. Check for "http://www.cancer.gov/Search/ClinicalTrialsLink.aspx?id=39752&idtype=1" active clinical trials or "http://www.cancer.gov/Search/ClinicalTrialsLink.aspx?id=39752&idtype=1&closed=1" closed clinical trials using this agent. ("http://nciterms.nci.nih.gov:80/NCIBrowser/ConceptReport.jsp?dictionary=NCI_Thesaurus&code=C367" NCI Thesaurus)
Concepts Pharmacologic Substance (T121) , Organic Chemical (T109)
MSH D002746
SnomedCT 387258005, 47331002
LNC LP16074-4, MTHU004251
English Chlorpromazine, 10H-Phenothiazine-10-propanamine, 2-chloro-N,N-dimethyl-, 2-Chloro-10-(3-(dimethylamino)propyl)phenothiazine, chlorpromazines (medication), chlorpromazines, Chlorpromazine [Chemical/Ingredient], chlorproMAZINE, chlorpromazine, CHLORPROMAZINE, CPZ - Chlorpromazine, Chlorpromazine (product), Chlorpromazine (substance)
Swedish Klorpromazin
Czech chlorpromazin
Finnish Klooripromatsiini
Russian AMINAZIN, KHLORPROMAZIN, АМИНАЗИН, ХЛОРПРОМАЗИН
Japanese クロルプロマジン
Croatian KLORPROMAZIN
Spanish clorpromazina (producto), clorpromacina (producto), clorpromacina, Clorpromacina, clorpromacina (sustancia), clorpromazina (sustancia), clorpromazina, Clorpromazina
Polish Largactil, Fenactil, Chloropromazyna
French Chlorpromazine
German Chlorpromazin
Italian Cloropromazina
Portuguese Clorpromazina

Ontology: Thorazine (C0699065)

Concepts Pharmacologic Substance (T121) , Organic Chemical (T109)
MSH D002746
English Thorazine, thorazine