en Pain and addiction Neurophysiology/Pharmacology Experimental research article Experimental research article <div style="text-align: justify;"><strong>Introduction: </strong>Pain is an unpleasant sensory and emotional experience. Evidence suggests a role for microglia in chronic pain and inhibition of microglia leads to decrease of chronic pain intensity in animal models. Minocycline, a semisynthetic tetracycline derivative, is a selective inhibitor of microglia. Several studies have shown pain intensity improvement by minocycline in animal model of pain, but a few studies showed effectiveness on chronic pain improvement in humans. This prospective, self-controlled clinical trial investigated whether minocycline is effective for chronic pain management. <strong>Methods: </strong>Twenty-two patients, between the ages of 20 and 80 years with radicular lumbar pain with a numerical rating scale >4, who were unresponsive to other medications and had pain duration of >6 weeks were included in the trial. <strong>Results: </strong>Pain intensity, neuropathic pain and life quality scores assessed before and after treatment. All scores showed significant improvement after 2 weeks of treatment: 56%, 74% and 14%, respectively. <strong>Conclusion: </strong>Findings of this study suggest minocycline can effectively improve patients&rsquo; pain scores and quality of life, even in those with long-term duration of chronic pain and warrants further study.</div> Minocycline, Low back radicular pain, Chronic pain. 197 201 http://ppj.phypha.ir/browse.php?a_code=A-10-1320-1&slc_lang=en&sid=1 Sanaz Sha'abani 3200319475328460029448 3200319475328460029448 No Department of Anesthesiology, Saveh University of Medical Sciences, Saveh, Iran Sasan Gazerani s.gazerani@savehums.ac.ir 3200319475328460029449 3200319475328460029449 Yes Department of Physiology, Saveh University of Medical Sciences, Saveh,, Iran Maryam Ragheb 3200319475328460029450 3200319475328460029450 No Nursery School, Saveh University of Medical Sciences, Saveh, Iran Amir-Hossein Mirgalou-Bayat 3200319475328460029451 3200319475328460029451 No Department of Anesthesiology, Saveh University of Medical Sciences, Saveh, Iran Mark Kennet Huntington 3200319475328460029452 3200319475328460029452 No The Center for Family Medicine, University of South Dakota, Sanford School of Medicine, Sioux Falls, South Dakota, USA