Ecstasy is a widely abused psychoactive recreational drug that is known to induce neuroplastic effects. The molecular basis of addiction remains poorly understood, but diverse lines of evidence suggest that neurotrophins (BDNF, NT-3 and NT-4) play a role in the regulation of synaptic plasticity. The present study was designed to evaluate the alteration of NT-4 protein levels and gene expression in the brain stem, cerebellum and cerebral hemisphere of rat brains in the context of ecstasy dependence. Ecstasy addiction was induced by intraperitoneal injection of ecstasy (10 mg/kg) for 5 days. After chronic ecstasy treatment, the NT-4 levels in the abovementioned areas of the brain were determined by ELISA. There was a significant increase in the NT-4 protein concentration in the brain stem, cerebellum and cerebral hemisphere when compared with control group. Additionally, these regions were assayed for the transcription of NT-4 using semi-quantitative RT-PCR normalized to β-actin gene transcription. The results show that chronic administration of ecstasy significantly increased NT-4 gene expression in the abovementioned areas of brain. The current work demonstrates that ecstasy induced-maladaptations may be regulated by NT-4.