Previous research has demonstrated that patients treated with the second-generation antipsychotic olanzapine (OLA) have metabolic dysfunctions and insulin resistance. Researchers from Instituto de Investigaciones Biomedicas “Alberto Sols” and collaborators investigated the impact of intraperitoneal (i.p.) OLA treatment on peripheral insulin sensitivity as well as potential effects of inhibiting the protein tyrosine phosphatase 1B (PTP1B), a negative regulator of insulin signaling.