Trichotillomania Associated With Aripiprazole: A Case Report
Aripiprazole, a novel antipsychotic agent, is the first dopamine D2/D3 receptor partial agonist. Besides its partial agonist effect on dopaminergic receptors, it also has partial agonist properties at 5-HT1A and 5-HT7 serotonin receptors. It has a higher affinity for D2 receptors than for 5-HT1A receptors. Its partial agonist effect may cause hyperactivity of the dopaminergic pathways. There is a circuitry starting from dorsal striatum, extending to thalamus and then to orbitofrontal cortex before finally inserting back into dorsal striatum. It is suppressed by the orbitofrontal cortex. For this circuitry, if orbitofrontal cortex does not suppress adequately, compulsive behavior may result. Impulsivity converts compulsivity because of the dysregulation of ventral stimulation or the lack of dorsal inhibition. Modulation of neurotransmission by dopaminergic system from the ventral tegmental area to Nuc. Accumbens (Nac), named mesolimbic dopaminergic pathway, has been studied repeatedly.1 This pathway plays a significant role in emotional behaviors. Hypoactivity of this pathway causes negative and cognitive symptoms of schizophrenia. The activation of D2-like receptors in the NAc supprresses dorsal inhibition. D3 receptor is a part of the D2-like receptor family and is predominantly concentrated in the nucleus accumbens and olfactory tubercle. These nuclei are related to motivation, reward, and cognitive functions. D3 receptor are also autoreceptor reducing the dopamine production and release. So aripiprazole- D2/D3 partial agonist may exacerbate positive symptoms of schizophrenia, but it may improve both negative symptoms and extrapyramidal side effects.2
Although studies have examined the association between aripiprazole and impulse control disorders or obsessive-compulsive symptoms,3–8 the association of trichotillomania with atypical antipsychotic agents is not widely studied. A possible association between trichotillomania and atypical antipsychotics, such as olanzapine, risperidone, quetiapine, and clozapine has been reported,9 and the literature contains a few case reports of trichotillomania associated with dopaminergic agents like stimulants.10–13
There is evidence that aripiprazole is used for the treatment of trichotillomania, but in the present case report, we aimed to present an adolescent male patient who was diagnosed with trichotillomania during his treatment with aripiprazole.