Tehran University of Medical Sciences Acta Medica Iranica 0044-6025 58 5 2020 08 10 194 198 Abolfazl Ghoreishi Department of Psychiatry, Social Determinants of Health Research Center, Metabolic Research Center, Zanjan University of Medical Sciences, Zanjan, Iran Saeed Granpy Department of Psychiatry, Zanjan University of Medical Sciences, Zanjan, Iran. Alireza Armani Department of Psychiatry, Zanjan University of Medical Sciences, Zanjan, Iran. 2019 12 02 2020 04 27 This study was conducted to compare the neurocognitive changes in an episode of primary psychosis in a group treated with minocycline and control. In this randomized controlled clinical trial, 40 patients with schizophrenia were randomized into two groups and underwent eight weeks of treatment with either minocycline (100 mg twice per day) or placebo in addition to routine treatment. Patients were evaluated using the Wechsler Adult Intelligence Scale (WAIS), Positive and Negative Syndrome Scale (PANSS), and Wisconsin Card Sorting Test (WCST) at baseline and at weeks 4 and 8. General linear model repeated measures showed a significant effect for time treatment interaction on the scores of WAIS, PANSS, and WCST of patients in the minocycline group (P>0.05). Regardless of the type of intervention, there was a remarkable difference between the mean scores of WAIS, PANSS, and WCST measured on three stages. Minocycline seems to be a safe and effective adjuvant in the management of patients with schizophrenia. https://acta.tums.ac.ir/index.php/acta/article/view/8203 https://acta.tums.ac.ir/index.php/acta/article/download/8203/5398