Background: Adult neurogenesis observed both in the subventricular zone (SVZ) and hippocampus may be regulated and modulated by several endogenous factors, xenobiotics and medications. Classical and atypical antipsychotic drugs are able to affect neuronal and glial cell proliferation in the rat brain. The main purpose of this structural study was to determine whether chronic chlorpromazine treatment affects adult neurogenesis in the canonical sites of the rat brain. At present, the clinical application of chlorpromazine is rather limited; however, it may still represent an important model in basic neuropharmacological and toxicological studies. Methods: The number of neural progenitors and immature neurons was enumerated using immunofluorescent detection of Sox2, Musashi1 and doublecortin (DCX) expression within SVZ. Results: Chlorpromazine has a depressive effect on the early phase of adult neurogenesis in the rat subventricular zone (SVZ), as the mean number of Sox-2 immunoexpressing cells decreased following treatment. Conclusion: Collectively, these results may suggest that long-term treatment with chlorpromazine may decrease neurogenic stem/progenitor cell formation in the rat SVZ and may affect rostral migratory stream formation.