Promethazine overdose


Promethazine is a medicine used to treat nausea and vomiting. Promethazine overdose occurs when someone takes too much of this medicine. It is part of a class of drugs called phenothiazines. This is for information only, not for use in treating or managing an actual overdose. DO NOT use it to treat or manage an actual overdose. If you or anyone is suffering from an overdose, call your local emergency number or your local poison center can be contacted directly by calling the toll-free National Poisoning Helpline.

Promethazine may be sold under the following brand names: Anergan; Fargan; Phenergan; Promahist; Promethegan; V-Gan. Note: this list cannot be comprehensive.


Promethazine overdose

Bladder and kidneys: urinary indecision; inability to urinate.
Heart and blood vessels: rapid heartbeat; weakness from low blood pressure.
Nervous system: drowsiness or even coma; agitation, confusion, agitation, disorientation; depression; nervousness, hallucinations; fever; instability; seizures; Tremors (unintentional trembling).
Other: flushed skin; involuntary tongue movement; large (dilated) pupils with visual disturbance; muscle stiffness of face or neck.

Before Calling an Emergency

The following information is useful for emergency care:
Age, weight, and condition of the person;
Name of product (and ingredients and strength, if known);
Time when it was ingested;
Amount ingested;
If the medicine was prescribed to the person;
However, DO NOT delay seeking help if this information is not immediately available.
Bring a container of pills with you if possible.

What to expect in the emergency room

Promethazine overdose

A health care professional will measure and monitor the person’s vital signs, including temperature, pulse, respiratory rate, and blood pressure. Symptoms will be treated accordingly. The person may receive: activated charcoal; airway support, including oxygen, oral airway (intubation) and ventilator (breathing machine); blood and urine tests; chest X-rays; heart monitoring; fluids through a vein (IV or I/V); laxatives; medications to treat symptoms.


If the person survives within the first 24 hours, recovery is possible. People who experience cardiac arrhythmias and seizures are at greatest risk for a serious outcome. Few people actually die from an overdose of promethazine.

Correct Dosage

Intravenous, intravenous, and intravenous. P/V is not administered, given its irritant effect. Orally, in adults 75-100 mg/day in 3-4 doses, the evening dose may be 50 mg. The highest single dose is 75 mg, the daily dose is 500 mg. The drug is administered intravenously in 1-2 ml of a 2.5% solution 3-4 times a day or 2 ml intravenously as part of a lytic mixture. The highest single dose for intravenous injection is 50 mg, the daily dose is 250 mg. As preparation for surgery to enhance general anesthesia: the night before take 25-50 mg together with other hypnotics; 2.5 hours before surgery, 50 mg/m with other components of lytic mixture in a syringe. Orally, in children 1-2 years – 5-10 mg 1-2 times daily; 2-5 years – 5-10 mg 1-3 times daily; 5-10 years – 5-15 mg 1-3 times daily; over 10 years and adolescents – 5-20 mg 1-3 times daily. Orally administered intravenously, 0.5-1 mg/kg, 3-5 times daily. In emergency cases, 1-2 mg/kg. B/V – 1/3 of the dose used for B/V administration. To prevent motion sickness: once 1 hour before travel, adults 25-50 mg, children 10-20 mg.