Aripiprazole
Aripiprazole
Purpose
Aripiprazole (brand name Abilify) is a newer generation antipsychotic medication. It was approved by the U.S. Food & Drug Administration (FDA) in 2002 to treat schizophrenia symptoms. The symptoms of schizophrenia include hallucinations, delusions, paranoia, and social withdrawal.
The drug is also FDA–approved as a therapy for people with bipolar disorder who have had episodes of acute mania or mixed episodes of mania and depression , but who have subsequently been stabilized for at least six weeks.
Aripiprazole can be used short-term to treat acute psychotic and manic states and agitation in dementia, as well as long-term to treat chronic psychotic disorders, such as schizophrenia. In the past, these conditions were typically treated with conventional antipsychotic drugs, such as phenothiazine, thioxanthene, and butyrophenone neuroleptics.
Although aripiprazole is primarily indicated for the treatment of adults, some studies have indicated that it also may be effective for children and adolescents with bipolar disorder. In the few studies that have been conducted, the drug was well tolerated in this population; however, researchers say that a lower dose is appropriate in younger patients.
Description
Aripiprazole is part of a class of drugs called atypical antipsychotics. This class, which also includes clozapine, olanzapine, quetiapine, risperidone, and ziprasidone, are called “atypical” because of their relatively lower risk of certain types of adverse side effects compared to traditional antipsychotic drugs.
The exact mechanism by which aripiprazole and other atypical antipsychotic drugs work is unknown. Scientists believe that schizophrenia is caused by an imbalance of dopamine in the brain. Dopamine is a neurotransmitter that affects movement and balance. The theory is that aripiprazole acts as a partial agonist and antagonist, meaning that it binds to dopamine receptors in the brain and partially activates these receptors, while preventing dopamine from binding to them and fully activating them. Conventional antipsychotic drugs, by comparison, act as full antagonists. These drugs completely block dopamine receptors and significantly interfere with dopamine transmission, which can cause severe movement side effects. Aripiprazole also affects another neurotransmitter, serotonin, which is involved in regulating mood, and which is also imbalanced in people with schizophrenia.
Although studies suggest that aripiprazole works well to treat psychotic conditions such as schizophrenia, very little research has been conducted comparing its effectiveness with that of conventional antipsychotic drugs.
Recommended Dosage
Aripiprazole is only available by prescription. It is taken once a day by mouth as either a tablet or an oral solution. The oral solution is designed for older patients who have difficulty swallowing a tablet. Tablets range from 2 mg to 30 mg strengths. The oral solution is available in a 1-mg/mL solution. Aripiprazole can be taken with or without food. Some patients start out on a low dose, and then their doctor increases the dose after approximately two weeks.
Precautions
Women who are pregnant, who intend to become pregnant, or who are nursing should ask their doctor before taking this drug. Aripiprazole may increase the risk for diabetes, and people who develop extreme thirst, frequent urination, or other diabetes symptoms while taking the drug should see a doctor for assessment.
Because of potential interactions, people who are taking aripiprazole should tell their doctor if they have or are taking medications for any of the following conditions:
- Alzheimer’s disease
- Anxiety
- Depression
- Diabetes
- Heart disease or heart failure
- High or low blood pressure
- Human immunodeficiency virus (HIV)
- Irritable bowel disease
- Mental illness
- Parkinson’s disease
- Seizures
- Stroke or mini-stroke
- Surgery
- Ulcers
Because this medication may cause drowsiness and can impair judgment and motor skills, people who take it should take precautions when operating a motor vehicle or machinery. Alcohol can increase the sedative effects, and is not advised for people who are taking aripiprazole. Also, people who take this drug should use caution when exercising, because aripiprazole can affect the body’s ability to regulate temperature, potentially leading to overheating and dehydration.
Side Effects
Aripiprazole and other atypical antipsychotic drugs tend to cause fewer neurological side effects than the older antipsychotic drugs. In particular, they have a lower risk of extrapyramidal symptoms, a group of involuntary muscle movement disorders. However, the drug does have side effects.
The most common side effects with aripiprazole are:
- anxiety
- constipation
KEY TERMS
Atypical antipsychotic —A class of newer-generation antipsychotic medications that are used to treat schizophrenia and other psychotic disorders.
Bipolar disorder —A brain disorder that causes extreme emotional shifts, or mood swings.
Delusions —A condition in which a person experiences beliefs that are untrue.
Dementia—A loss of mental ability, often occurring with age, that can interfere with a person’s ability to think clearly and function independently.
Dopamine —A chemical messenger in the brain that regulates movement and balance.
Extrapyramidal —Related to the motor system in the brain. Extrapyramidal symptoms affect movement and coordination.
Hallucinations —Seeing, hearing, feeling, smelling, or tasting things that do not exist.
Mania —A mood disorder in which a person may become impulsive or irritable, and may exercise extremely poor judgment.
Neuroleptic malignant syndrome —A rare response to certain antipsychotic drugs, which can raise the body temperature to potentially life-threatening levels.
Serotonin —A chemical messenger in the brain that affects mood and emotion.
Paranoia —Condition in which a person has an irrational suspicion about another person or situation.
Partial agonist —A substance that partially activates a receptor in the brain, while blocking the neurotransmitter for that receptor from binding to it.
Schizophrenia —A mental disorder in which a person experiences hallucinations and delusions, and displays unusual behavior.
- difficulty sleeping
- dizziness
- drowsiness
- headache
- nausea
- nervousness
- numbness
- tremor
- vomiting
- weight gain
This drug can increase the risk for a rare condition called neuroleptic malignant syndrome (NML). This condition, which is sometimes caused by drugs that interfere with the dopamine pathway, can raise body temperatures to potentially life-threatening levels.
Aripiprazole is not approved for the treatment of psychosis in elderly patients with dementia. The FDA in 2005 released a public health advisory warning patients and doctors against using aripiprazole and other atypical antipsychotics off-label. In studies, these drugs significantly increased the risk of death in older patients with dementia compared to placebo. Most of the deaths were associated with heart failure or infections such as pneumonia. Atypical antipsychotics also have been associated with an increased risk for stroke in elderly patients with dementia-related psychosis.
Interactions
Aripiprazole can have potentially dangerous interactions with the following drugs:
- famotidine
- valproate
- lithium
- dextromethorphan
- warfarin
- omeprazole
- lorazepam
Resources
BOOKS
Beers, Mark H. The Merck Manual of Medical Information: 2nd Home Edition. New York, NY: Pocket, 2004.
Mondimore, Francis Mark. Bipolar Disorder: A Guide for Patients and Families, 2nd edition. Baltimore, MD: The Johns Hopkins University Press, 2006.
Stahl, Stephen M. Essential Psychopharmacology: The Prescriber’s Guide: Antipsychotics and Mood Stabilizers. New York, NY: Cambridge University Press, 2006.
Torrey, E. Fuller. Surviving Schizophrenia: A Manual for Families, Patients, and Providers. 5th edition. New York, NY: Harper Collins Publishers, 2006.
ORGANIZATIONS
American Psychiatric Association. 1000 Wilson Boulevard, Suite 1825, Arlington, VA 22209-3901. Telephone: (703) 907-7300. <http://www.psych.org/>.
National Alliance on Mental Illness. 2107 Wilson Blvd., Suite 300, Arlington, VA 22201-3042. Telephone: (800) 950-6264. <http://www.nami.org>.
National Institute of Mental Health. 6001 Executive Boulevard, Room 8184, MSC 9663 Bethesda, MD 20892-9663. Telephone: (866)615-6464. <http://www.nimh.nih.gov/>.
The Mental Health Research Association. 60 Cutter Mill Road, Suite 404, Great Neck, NY 11021. Telephone: (800) 829-8289. <narsad.org>.
Stephanie N. Watson