Chlorpromazine is an antipsychotic medication used to treat schizophrenia, some types of bipolar disorder, severe agitation, persistent hiccups, nausea, and vomiting. It may also be used for certain other conditions under a doctor's supervision.

Chlorpromazine can cause side effects such as weight gain, drowsiness, restlessness, difficulty controlling body movements, and severe allergic reactions. Because of these risks, it should only be used as prescribed by a doctor.

In the United States, chlorpromazine is available by prescription as a generic medication, including oral tablets. The former brand-name medication Thorazine is no longer marketed in the US, although generic chlorpromazine remains available.

What is chlorpromazine used for?

Chlorpromazine may be used to treat:

Acute psychiatric conditions, such as psychotic episodes or manic episodes associated with bipolar disorder;
Long-term psychotic disorders, such as schizophrenia;
Severe agitation;
Anxiety;
Persistent hiccups;
Nausea and vomiting;
Pain during labor;
Eclampsia;
Tetanus, as an adjunctive medication.

A doctor may also sometimes prescribe chlorpromazine as an adjunctive treatment for serotonin syndrome or to relieve migraine symptoms such as nausea and vomiting.

Can chlorpromazine be used for sleep?

Chlorpromazine is not a sleep medication. However, drowsiness is a common side effect during treatment, especially in the first few hours after taking the medication.

Check out a list of sleeping pills, supplements and herbs that your doctor can prescribe for insomnia instead.

How to take

Chlorpromazine tablets should be taken by mouth with liquids. The tablets should not be split or chewed unless specifically instructed by a doctor or pharmacist.

For young children or people who have difficulty swallowing tablets, an oral liquid formulation may be more appropriate and should be used according to a doctor's instructions.

1. Chlorpromazine hydrochloride 25 mg

Chlorpromazine hydrochloride 25 mg tablets may be used as follows:

Children over 2 years old: the initial daily dose of chlorpromazine is 1 mg/kg of body weight per day, divided into 2 or 3 doses. The maximum dose is 40 mg per day for children under 5 years old and 75 mg per day for older children;
Adults: the initial dose ranges from 1 to 4 tablets of 25 mg and may be repeated up to 3 or 4 times per day if necessary. The doctor may increase the dose based on symptom control, up to a maximum of 2 g per day;
Adults 65 years and older: the initial chlorpromazine dose should generally be about half the usual adult dose, with gradual increases according to the doctor's instructions.

Chlorpromazine may be prescribed for children, adolescents, and adults. Recommended doses vary depending on age and the severity of symptoms, and the doctor's instructions should be followed carefully.

2. Chlorpromazine hydrochloride 100 mg

Chlorpromazine hydrochloride 100 mg tablets may be used as follows:

Adults: the recommended initial dose of chlorpromazine 100 mg is up to 1 tablet and may be repeated up to 3 or 4 times per day if necessary. The dose should be increased gradually by the doctor based on symptom control, up to a maximum of 2 g per day;
Adults 65 years and older: the initial chlorpromazine dose should generally be approximately half the usual adult dose, with slow increases according to the doctor's instructions.

Chlorpromazine 100 mg is generally less suitable for children because pediatric doses are usually lower. A doctor may instead prescribe a lower-strength tablet or an appropriate oral liquid formulation.

Possible side effects

The most common side effects of chlorpromazine include:

Weight gain;
Drowsiness;
Restlessness;
Dry mouth;
Dizziness;
Constipation;
Urinary retention.

Although uncommon, difficulty controlling body movements and serious side effects such as sudden death, abnormal heart rhythms, and severe allergic reactions may also occur during treatment.

Chlorpromazine can also cause high prolactin levels in the blood, which may cause symptoms such as decreased libido and breast milk production.

When chlorpromazine should not be used

Chlorpromazine should not be used by people who have had a severe allergic reaction to chlorpromazine or other phenothiazines. It is also contraindicated in people who are in a coma or who have taken large amounts of central nervous system depressants.

People with conditions such as angle-closure glaucoma, urinary retention or an increased risk of urinary retention due to an enlarged prostate, heart problems, or other significant medical conditions should tell their doctor before using chlorpromazine. Possible interactions with medications such as levodopa and escitalopram should also be reviewed by the prescribing doctor.

Chlorpromazine should generally not be used in infants younger than 6 months except in potentially lifesaving situations. During pregnancy or breastfeeding and in older adults, chlorpromazine should only be used when prescribed and monitored by a doctor.

Chlorpromazine: Indications, How to Take, Dosing & Side Effects