Clozapine: A Possible Treatment for Schizophrenia

          The overuse of cannabis during adolescence has been recently linked as a precursor to psychosis later on. The primary brain area affected by cannabis overuse is the hippocampus, associated with memory and learning. It is deduced that the effect of cannabis overuse disorder (or CUD) is the eventual deterioration of this brain area, seen with schizophrenics primarily as delusions. Dr. John Csernansky visited Loyola University Chicago to talk to us about his recent research on this topic. He conducted a study on effects of CUD on normal brains versus the brains of schizophrenic patients. The study was able to conclude that individuals with CUD had brain regions that were deteriorating as a result of heavy drug use in their adolescence, both in the control group and the schizophrenic group. However, the schizophrenic individuals had higher levels of deterioration in multiple brain regions, especially in the hippocampus. Dr. Csernansky and his colleagues concluded that there was a correlation with CUD and significant destruction of brain regions in schizophrenic individuals, indicating that their brains are especially susceptible to any kind of damage.

Hippocampal region decrease in Cannabis user with schizophrenia

          Similarly, there was as study conducted on the treatment of schizophrenia with a certain antipsychotic, Clozapine. The study examined the correlation between Clozapine use and the eventual decrease in alcohol and drug use of schizophrenic patients. Researchers observed over a period of a year whether individuals treated with Clozapine were more successful in their abstinence than individuals treated with another antipsychotic drug, Risperidone. They observed that individuals prescribed the Clozapine treatment were in fact abstinent from alcohol and drug use over that period of time, compared to individuals treated with Risperidone.  The patients on the Risperidone treatment were stopping the treatment for ineffectiveness before the study was completed, compared to the patients on Clozapine, who finished the study in its entirety. Researchers were still unsure of whether Risperidone had any beneficial effects, especially with no patient data as a result of their stopped treatments, however, they were able to obtain statistically significant results on Clozapine benefits in schizophrenic individuals. The effects of Clozapine have been linked to a decrease in overall negative effects of schizophrenia, some of which are anhedonia, flat affect, and lack of social interest. Researchers believe that the use of Clozapine may relieve these negative effects and therefore contribute to more positive emotions in schizophrenic patients, eventually causing a decreased need for substance use. This finding indirectly contributes to stopping the deterioration of the hippocampus, as discussed with Dr. Csernansky’s work, as it relieves schizophrenic patients use of substances, the possible cause of hippocampal damage in these individuals. Though it is most likely not possible to reverse the damage already caused by adolescent CUD, stopping the progression of brain damage is a promising step in helping schizophrenics become healthier and hopefully continue to improve with their condition later on.

Sources:
Green, Alan, Ellen S. Burgess, Ree Dawson, Suzannah V. Zimmet, and Rael D. Strous. "Alcohol and Cannabis Use in Schizophrenia: Effects of Clozapine vs. Risperidone." http://www.sciencedirect.com/. Science Direct, 1 March. 2003
Smit, Filip, Linda Bolier, and Pim Cuijpers. "Cannabis Use and the Risk of Later Schizophrenia: A Review." Society for the Study of Addiction, 25 March. 2004.

Ashtari, Manzar, Brian Avants, and Laura Cyckowski. "Medial Temporal Structures and Memory Functions in Adolescences with Heavy Cannabis Use." www. sciencedirect.com. Science Direct, August. 2011


Photo:

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