Olanzapine is associated with the highest placental exposure of any atypical antipsychotic. Paliperidone is the primary active metabolite of the older antipsychotic risperidone. The use of the antipsychotic agent clozapine is associated with neutropenia. The antipsychotic haloperidol may also be used. Olanzapine, another sedating second-generation antipsychotic, has also been abused for similar reasons. The most commonly second-generation antipsychotic implicated in abuse is quetiapine. The mode of action of olanzapine's antipsychotic activity is unknown. Sertindole appears effective as an antipsychotic in schizophrenia. Tardive dyskinesia may abate during withdrawal from the antipsychotic agent, or it may persist. The drug is also commonly used to treat extrapyramidal side effects occurring during antipsychotic treatment. Akathisia is frequently associated with the use of dopamine receptor antagonist antipsychotic drugs. Trifluoperazine is an effective antipsychotic for people with schizophrenia. Benzatropine is used to reduce extrapyramidal side effects of antipsychotic treatment. As noted, side effects are associated with antipsychotic medication. Treatment is generally therapy, often with support of antipsychotic medication.