HTR2A and autism: Several published reports have suggested the clinical effectiveness of risperidone, and a randomized controlled trial demonstrated the effectiveness of risperidone in the short-term treatment of symptoms of autism in adults [16]. Aripiprazole is also an atypical antipsychotic with potent partial agonism at dopamine D2 receptors in addition to properties as a 5-HT1A agonist and 5-HT2 antagonist [17].