This article will investigate its uses, modes of action, side effects and precautions.
- What is aripiprazole?
- When is aripiprazole used?
- How does aripiprazole work?
- Side effects of aripiprazole
- Important warnings for aripiprazole
- Current research into aripiprazole
Here are some key points about aripiprazole. More detail and supporting information is in the main article.
- Aripiprazole is classed as an atypical antipsychotic.
- The drug is used for a number of conditions, most commonly schizophrenia.
- The exact mode of action for aripiprazole is still unclear.
- Aripiprazole can be useful in the treatment of certain autistic symptoms.
- Side effects can include aching limbs, dizziness and seizures.
- Aripiprazole was first approved for use in schizophrenia in 2002.
- In rare cases, it can cause neuroleptic malignant syndrome.
- Aripiprazole is being investigated for a potential role in the treatment of cocaine addiction.
What is aripiprazole?
Aripiprazole is an antipsychotic that works at a number of receptors and transporters.
Aripiprazole is classed as an atypical (second-generation) antipsychotic. It works at a large number of sites, including receptors and transporters.
Its chemical name is C23H27Cl2N3O2
The drug mediates its action by either blocking receptors (antagonist) or by binding to them and inducing an opposite response to receptor's normal role (inverse agonist).
Aripiprazole exerts its impact via various receptors including multiple subtypes of serotonin, dopamine, adrenergic, muscarinic acetylcholine and histamine receptors. It also works on serotonin, norepinephrine and dopamine transporter proteins.
The drug was first approved by the US Food and Drug Administration (FDA) for use in schizophrenia in 2002.
When is aripiprazole used?
Aripiprazole is used predominantly for the treatment of schizophrenia and bipolar disorder but can also be used as an add-on treatment for major depressive disorder, tic disorders, obsessive-compulsive disorders and irritability associated with autism.2
Schizophrenia was the first illness to be targeted by aripiprazole. The decision by the FDA to approve its use was based on clinical trials that showed aripiprazole's ability to lessen psychotic episodes and reduce relapses when compared to a placebo.
The current consensus of scientific opinion is that aripiprazole's effect is comparable to a number of other typical and atypical antipsychotics. It has fewer side effects than some, but more than others.3 Aripiprazole is considered a middle-range antipsychotic regarding its effectiveness.4
Aripiprazole can be effective in treating the acute manic episodes of bipolar disorder in adults, adolescents and children.
However, its effect is only useful for the manic phases with little or no effect on the depressive phases. For this reason, aripiprazole is often used in conjunction with mood stabilizers. This dual approach is effective, but increases the risk of movement disorders (extrapyramidal symptoms).5
Some patients are prescribed aripiprazole in conjunction with antidepressants, however, as above, this increases the risk of movement disorders; there is also an additional risk of weight gain.
Aripiprazole can be useful in reducing some aspects of autistic behavior. Studies show that it can reduce irritability, hyperactivity and repetitive movements (stereotypy) in autistic children and youths.
The side effects include weight gain, drooling, tremors and sleepiness.
There is some evidence that low doses of aripiprazole can yield positive results in obsessive-compulsive disorders (OCD) that are resistant to selective serotonin reuptake inhibitors (SSRI) alone.6
How does aripiprazole work?
As with other atypical antipsychotics, the exact method of action for aripiprazole is not known. The design of the drug was based on the dopamine hypothesis.
The dopamine hypothesis predicts that dopamine hyperactivity in the mesolimbic pathways of the brain (also known as reward pathways) causes delusions, hallucinations and disorganized thoughts.
Dopamine inactivity in the mesocortical pathways (involved in cognitive control, motivation and emotional response) and the prefrontal cortex (an area implicated in planning complex cognitive behavior and moderating social behavior) leads to an impairment in linguistic ability, an inability to experience pleasure and autism.7
Aripiprazole's effects at dopamine receptors are thought to decrease dopamine production and stabilize the dopamine system.8
On the next page, we look at the side effects for aripiprazole, related warnings and current research.