What Is Promazine?

Promazine is a medication prescribed to help treat psychotic thoughts, very restless or agitated behavior, and delusions. It is a phenothiazine anti-psychotic drug that works by reducing the effects of dopamine in the brain to help control behaviors, moods, and thoughts. The medicine blocks receptors in the brain that use dopamine. As of 2011, promazine is no longer available on the market in the United States, however it may be prescribed in other countries.

This drug is typically prescribed on a short-term basis. Patients should not use it longer than recommended by a doctor, because long-term use could lead to permanent, involuntary muscle movements called tardive dyskinesia. It can also cause vision disturbances, so patients should see an eye doctor regularly.

Elderly patients may be more susceptible to developing side effects from promazine, so they should begin treatment with a low dose. Low blood pressure is possible, so elderly patients should take care not to lose their balance when standing up. They may also have an increased risk of a stroke. Children should only use this medicine under a pediatrician's close supervision. It is generally not advised to give promazine to a child.

Some side effects have been reported with the use of promazine. It may result in nasal congestion, blurred vision, and dry mouth. Constipation and drowsiness may also occur, along with insomnia, difficult urination, and sexual problems.

Severe or persistent side effects may require immediate medical attention. These can include jaundice, rapid or abnormal heartbeat, and abnormal muscle movements. Convulsions, clouding of the eye, and a lowering of the white blood cell count may occur. Neuroleptic malignant syndrome is also possible, which is indicated by the loss of consciousness, fever and sweating, as well as a rapid heartbeat and paleness.

As of 2011, it is unknown whether promazine can cause birth defects. Pregnant women should avoid use whenever possible. Promazine does pass into breast milk, so patients who are breastfeeding should not use it. Other medical conditions that can contraindicate its use include an adrenal gland tumor, glaucoma, and diabetes, because it may elevate blood sugar levels. Patients with epilepsy, hypothyroidism, or Parkinson's disease should not use this drug.

Alcohol should be avoided while taking promazine. Patients must disclose all their medications and supplements before taking it to avoid an interaction. For example, it should not be combined with antidepressants, antihistamines, or other anti-psychotic drugs. Narcotics, sleeping pills, and muscle relaxants may also interact with this medicine.