Promazine Side Effects

Promazine is a phenothiazine antipsychotic medication prescribed to calm severely agitated or restless behavior, primarily in people who are mentally ill. Promazine blocks some receptors in the brain, particularly dopamine receptors, and produces a sedative effect. Numerous side effects are possible.

Most Common Effects

• The most common side effects associated with promazine include blurred vision, constipation, difficulty urinating, drowsiness, dry mouth, lethargy, sleepiness, stiffness and weight gain.

Low Blood Pressure

• Promazine can cause a drop in blood pressure when people get up from sitting or lying down. This can result in dizziness and lightheadedness and, in severe cases, fainting.

Less Common Effects

• Many other less common side effects are possible. These include confusion, increased sensitivity of skin to sunlight, insomnia, nasal congestion and sexual problems.

Temperature Regulation

• Promazine can interfere with the body's temperature regulation in very hot weather or very cold weather, most commonly in elderly people. This can result in heat stroke in hot weather and hypothermia in cold weather.

Serious Side Effects

• Serious side effects call for medical attention. These include clouding of the eyes, decreased white blood cell count, increased heart rate or irregular heart rhythm, jaundice, seizures and a skin rash, which may indicate an allergy.

Warning

• Promazine also is linked to development of tardive dyskinesia, which causes involuntary and repetitive body movements; and neuroleptic malignant syndrome, a life-threatening neurological disorder.