In summary, the statistical analysis revealed the following: (a) a significant concentration decrease in pro-inflammatory cytokines IL-6 (p = 0.012), IL-12 (p = 0.049) and anti-inflammatory IL-10 (p = 0.012) post-ECT vs. pre-ECT; (b) no significant change in IL-5 and TGF-β1 concentration post-ECT vs. pre-ECT; (c) a significant decrease (p < 0.001) in schizophrenia symptoms (a significant decrease in all subscales: positive, negative, general PANSS) and total PANSS score led by ECT; (d) a negative correlation between TGF-β1 and PANSS positive symptoms (r = −0.790, p = 0.05) post-ECT. Here, IL6 is linked to schizophrenia.