Trifluoperazine

Trifluoperazine

Definition

Trifluoperazine is a phenothiazine antipsychotic agent. In the United States, this drug is sold under the brand name Stelazine.

Purpose

Trifluoperazine is a drug used to treat psychotic disorders, agitation, and dementia .

Description

Trifluoperazine is an effective agent in treating symptoms of psychotic behavior. When used for the treatment of schizophrenia , trifluoperazine reduces symptoms of emotional withdrawal, anxiety, tension, hallucinations , and suspiciousness.

Recommended dosage

The dosage of trifluoperazine should be adjusted to the lowest level needed to control symptoms. The drug may be given orally or by intramuscular injection (a shot).

A useful initial dosage of trifluoperazine for psychotic adults is 2 to 5 mg two times each day. A common total dosage is 15 to 20 mg per day. Some persons may require up to 40 or more mg per day. When using deep intramuscular injection, 1 to 2 mg every four to six hours is usually sufficient to control symptoms within 24 hours. Total intramuscular trifluoperazine should not exceed 10 mg per day.

Control of psychotic symptoms in children between the ages of six and 12 can usually be achieved with 1 to 2 mg per day, given in 1-mg increments. Trifluoperazine is not recommended for use in children younger than six.

Precautions

Trifluoperazine increases the level of prolactin, a hormone that stimulates the mammary glands in the breast, in the blood. This is a potential problem for persons with a personal or family history of breast cancer and may increase the risk of breast cancer. For this reason, the benefits and risks of the drug must be carefully evaluated before it is administered.

Side effects

Relatively common side effects that accompany trifluoperazine include drowsiness, dizziness, rash, dry mouth, insomnia , fatigue , muscular weakness, anorexia, blurred vision, some loss of muscular control, and amenorrhea (lack of menstruation)in women.

Dystonia (difficulty walking or moving) may occur with trifluoperazine use. This condition may subside in 24 to 48 hours even when the person continues taking the drug and usually disappears when trifluoperazine is discontinued.

Trifluoperazine use may lead to the development of symptoms that resemble Parkinson's disease. These symptoms may include a tight or mask-like expression on the face, drooling, tremors, pill-rolling motions in the hands, cogwheel rigidity (abnormal rigidity in muscles characterized by jerky movements when the muscle is passively stretched), and a shuffling gait. Taking anti-Parkinson drugs benztropine mesylate or trihexyphenidyl hydrochloride along with the trifluoperazine usually controls these symptoms.

Trifluoperazine has the potential to produce a serious side effect called tardive dyskinesia . This syndrome consists of involuntary, uncoordinated movements that may appear late in therapy and may not disappear even after the drug is stopped. Tardive dyskinesia involves involuntary movements of the tongue, jaw, mouth or face or other groups of skeletal muscles. The incidence of tardive dyskinesia increases with increasing age and with increasing dosage of trifluoperazine. Women are at greater risk than men for developing tardive dyskinesia. There is no known effective treatment for tardive dyskinesia, although gradual (but rarely complete) improvement may occur over a long period.

An occasionally reported side effect of trifluoperazine is neuroleptic malignant syndrome. This is a complicated and potentially fatal condition characterized by muscle rigidity, high fever, alterations in mental status, and cardiac symptoms such as irregular pulse or blood pressure, sweating, tachycardia (fast heartbeat), and arrhythmias (irregular heartbeat). People who think they may be experiencing any side effects from this or any other medication should talk to their physician promptly.

Interactions

Trifluoperazine may reduce the effectiveness of oral anticoagulant (blood thinning) drugs.

Trifluoperazine increases the effect of drugs and substances that depress the central nervous system and. These drugs include anesthetics, opiates, barbiturates , atropine, and alcohol. These substances should be avoided or used sparingly by people taking trifluoperazine.

Propranolol increases the concentration of trifluoperazine. The blood pressure-lowering effects of guanethidine may be diminished by trifluoperazine. The use of diuretics with trifluoperazine may cause a sudden decrease in blood pressure often accompanied by dizziness due to a change in body position (known as orthostatic hypotension).

The blood concentration of phenytoin is increased by trifluoperazine. This may lead to phenytoin toxicity.

Resources

BOOKS

Adams, Michael and Norman Holland. Core Concepts in Pharmacology. Philadelphia: Lippincott-Raven, 1998.

Foreman, John C. and Torben Johansen. Textbook of Receptor Pharmacology. 2nd ed. Boca Raton, FL: CRC Press,2002.

Page, Clive P., and Michael Murphy. Integrated Pharmacology. St. Louis: Mosby-Year Book, 2002.

Von Boxtel, Chris J., Budiono Santoso, and I. Ralph Edwards. Drug Benefits and Risks: International Textbook of Clinical Pharmacology. New York: John Wiley and Sons,2001.

PERIODICALS

Nelson J. C. "Diagnosing and treating depression in the elderly." Journal of Clinical Psychiatry 62, Supplement 24(2001): 18-22.

Pisani F., G. Oteri, C. Costa, G. Di Raimondo, and R. Di Perri. "Effects of psychotropic drugs on seizure threshold." Drug Safety 25, no. 2 (2002): 91-110.

Varvel A., E. Vann, E. Wise, D. Philibin, and H. Porter. "Effects of antipsychotic drugs on operant responding after acute and repeated administration." Psychopharmacology (Berlin) 160, no. 2 (2002): 182-191.

ORGANIZATIONS

American Academy of Clinical Toxicology. 777 East Park Drive, PO Box 8820, Harrisburg, PA 17105-8820. Telephone: (717) 558-7750. Fax: (717) 558-7845. Web site: <http://www.clintox.org/index.html>.

American Academy of Family Physicians, 11400 Tomahawk Creek Parkway, Leawood, KS 66211-2672. Telephone:(913) 906-6000. Web site: <http://www.aafp.org/>.

American Medical Association. 515 N. State Street, Chicago, IL 60610. Telephone: (312) 464-5000. Web site: <http://www.ama-assn.org/>.

American Psychiatric Association. 1400 K Street NW, Washington, DC 20005. Telephone: (888) 357-7924. Fax:(202) 682-6850. Web site: <http://www.psych.org/>.

American Society for Clinical Pharmacology and Therapeutics. 528 North Washington Street, Alexandria, VA 22314. Telephone: (703) 836-6981. Fax: (703) 836-5223.

American Society for Pharmacology and Experimental Therapeutics. 9650 Rockville Pike, Bethesda, MD 20814-3995. Telephone: (301) 530-7060. Fax: (301) 530-7061. Web site: <http://www.aspet.org/>.

L. Fleming Fallon, Jr., M.D., Dr.P.H.