From the Guidelines
The recommended dosage of chlorpromazine is 12.5-25 mg orally or per rectum, with the option to administer it every 6-12 hours if scheduled dosing is required, as stated in the most recent guidelines from 2018 1.
Key Considerations
- The dosage may need to be adjusted based on individual patient factors, such as age and renal or hepatic impairment.
- Chlorpromazine can cause side effects like sedation, orthostatic hypotension, and anticholinergic effects, which should be monitored and managed accordingly.
- The medication can be administered orally, intramuscularly, or rectally, with oral administration being most common for maintenance therapy.
Administration and Monitoring
- For adults with psychosis, the typical starting dose is 12.5-25 mg orally or per rectum, which may be gradually increased to an effective maintenance dose.
- Elderly patients generally require lower doses, typically starting at 10-25 mg 2-3 times daily.
- Dosage adjustments may be necessary based on patient response, side effects, and concurrent medications.
Comparison with Other Studies
- A previous study from 2014 1 suggested a starting dose of 12.5 mg every 4-12 hours, or 3-5 mg/h i.v. or 25-100 mg every 4-12 hours per rectum, but the most recent guidelines from 2018 1 provide more up-to-date and relevant information.
- The 2018 guidelines 1 provide a more comprehensive overview of the recommended dosage and administration of chlorpromazine, making it the preferred reference for clinical decision-making.
Clinical Decision-Making
- When prescribing chlorpromazine, clinicians should prioritize the patient's individual needs and medical history, and adjust the dosage accordingly to minimize side effects and optimize treatment outcomes.
- Regular monitoring of the patient's response to treatment and potential side effects is crucial to ensure safe and effective use of chlorpromazine.
From the FDA Drug Label
DOSAGE AND ADMINISTRATION–ADULTS Adjust dosage to individual and the severity of his condition, recognizing that the milligram for milligram potency relationship among all dosage forms has not been precisely established clinically. It is important to increase dosage until symptoms are controlled. Psychotic Disorders – Increase dosage gradually until symptoms are controlled Maximum improvement may not be seen for weeks or even months. Continue optimum dosage for 2 weeks; then gradually reduce dosage to the lowest effective maintenance level. Daily dosage of 200 mg is not unusual. Some patients require higher dosages (e.g., 800 mg daily is not uncommon in discharged mental patients). Hospitalized Patients: Acute Schizophrenic or Manic States – It is recommended that initial treatment be with chlorpromazine hydrochloride injection until patient is controlled. Usually patient becomes quiet and co-operative within 24 to 48 hours and oral doses may be substituted and increased until the patient is calm 500 mg a day is generally sufficient. While gradual increases to 2,000 mg a day or more may be necessary, there is usually little therapeutic gain to be achieved by exceeding 1,000 mg a day for extended periods.
The recommended dosage of chlorpromazine varies depending on the condition being treated and the individual patient's response.
- For psychotic disorders, the dosage should be increased gradually until symptoms are controlled, with a daily dosage of 200 mg being not unusual, and some patients requiring higher dosages of up to 800 mg daily.
- For hospitalized patients with acute schizophrenic or manic states, the initial treatment is usually with chlorpromazine hydrochloride injection, followed by oral doses of up to 500 mg a day, with gradual increases to 2,000 mg a day or more if necessary.
- For less acutely disturbed patients, the dosage is typically 25 mg t.i.d., increased gradually until the effective dose is reached, usually 400 mg daily.
- For outpatients, the dosage is typically 10 mg t.i.d. or q.i.d., or 25 mg b.i.d. or t.i.d. 2
From the Research
Dosage of Chlorpromazine
The recommended dosage of chlorpromazine varies depending on the condition being treated and the individual patient's response.
- The World Health Organization (WHO) lists chlorpromazine as one of its essential medicines for psychotic disorders 3.
- Studies have compared the effectiveness of low-dose (≤ 400 mg/day), medium-dose (401-800 mg/day), and high-dose (> 800 mg/day) chlorpromazine for schizophrenia and schizophrenia-like psychoses 3, 4.
- The results of these studies suggest that low-dose chlorpromazine may be as effective as medium-dose or high-dose chlorpromazine for some patients, with fewer extrapyramidal symptoms 3, 4.
- However, other studies have found that high-dose chlorpromazine may be more effective for some patients, particularly those with hyperactive delirium 5.
- The optimal dosage of chlorpromazine has not been established, and more research is needed to determine the most effective and safe dosage for different patient populations 3, 4, 6.
Factors Affecting Dosage
Several factors can affect the dosage of chlorpromazine, including:
- The severity of the patient's symptoms 3, 4
- The patient's age and medical history 5
- The presence of other medical conditions, such as liver or kidney disease 6
- The use of other medications that may interact with chlorpromazine 7
Administration
Chlorpromazine can be administered orally or intravenously, depending on the patient's needs and the severity of their symptoms 5.