A systematic review of atypical antipsychotics in chronic pain management: Olanzapine demonstrates potential in central sensitization, fibromyalgia, and headache/migraine

The previously-described surroundings of ineffective and even dangerous opioid therapies, it is warranted to examine the role of atypical antipsychotics (AAs) in pain management. Therefore, a systematic review conducted by Jimenez XF et al elaborated the efficacy safety, mechanism of action and risk/ benefit of using AAS in chronic pain management.  

Several psychopharmacologic agents are employed as adjunct or primary agents for managing pain. Atypical antipsychotics (AAs) have also been used as adjuncts for managing pain in various ways; although, their efficiency in this capacity is not clear.

All studies exploring AA use were reviewed under a systematic review. Evaluation of three literature databases was done using the word combinations of "pain" and diversity of commonly-prescribed AAs (Iloperidone, Ziprasidone, Olanzapine, Lurasidone, Risperidone, Paliperidone, Quetiapine, Aripiprazole, Clozapine) and picked randomised control trials, case series/reports, and retrospective analyses. A PRISMA diagram was used to represent the study selection method.

Aripiprazole, Risperidone, Ziprasidone, Olanzapine, and Quetiapine are the only AAs with published investigations in pain syndromes. Out of these, Quetiapine and Olanzapine presented the most combined studies. Olanzapine presents preliminary and uniform effectiveness in headache/migraine and fibromyalgia; however, only one investigation was a randomised controlled trial with Level I evidence of effectiveness. Other AAs (Quetiapine involved) fail to illustrate the efficiency in pain syndromes and/or lack strong study patterns.

Few investigations have been directed to assess the analgesic outcomes of AAs. The collective verdicts of multiple studies assessing Olanzapine in pain syndromes recommend a high yet preliminary level of evidence of effectiveness, warranting prospective studies in numerous pain syndrome settings. Pharmacological mechanisms of AA action are developed, and the verdicts of this review are explored. Benefits and risks of using AAs in chronic pain are refined, and investigational suggestions and future objectives are investigated.