Palmitoylethanolamide (PEA) emerged over the years as a promising approach in the management of chronic pain. Despite the fact that the efficacy of micron-size PEA formulations appears to be time-dependent, the optimal timing has not yet been elucidated. This systematic review and meta-analysis aim to estimate the possible advantage of an extended treatment in the relief of chronic pain. The literature search was conducted consulting scientific databases, to identify clinical trials in which micron-size PEA was administered for at least 60 days, and pain assessed by the Visual Analogue Scale (VAS) or Numeric Rating Scale (NRS). Nine studies matched the required criteria, for a total of 742 patients involved. The meta-analysis showed a statistically and clinically significant pain intensity reduction after 60 days of micron-size PEA supplementation, compared to 30 days (1.36 points, p < 0.01). The secondary analysis revealed a weighted NRS/VAS score decrease of 2.08 points within the first month of treatment. These two obtained scores corresponded to a 35.1% pain intensity reduction within the first month, followed by a further 35.4% during the second month. Overall, these results confirm the clinically relevant and time-depended pain-relieving effect of micron-size PEA and therefore the advantage of an extended treatment, especially in patient with incomplete pain management.

Background: Persistent Idiopathic Facial Pain (PIFP), previously named Atypical Facial Pain (AFP) is a poorly understood condition, often diagnosed after several inconclusive investigations. The aim of this retrospective study was to evaluate the demographic and clinical characteristics of patients with PIFP referred to a Facial Pain Center. Methods: Between May 2011 and September 2014, data on 41 PIFP patients were analyzed regarding temporal, topographical and descriptive pain features, including onset, localization, pain descriptors and intensity. Pharmacological pain treatments were also registered. Finally, the presence and type of previous minor oro-surgery procedures in the painful area were investigated. Results: Demographic and clinical characterization were similar to PIFP patients reported in literature. The presence of previous minor oro-surgery procedures in the painful area was reported in most of these patients, in particular endodontic treatments and tooth extractions. Conclusions: This retrospective analysis showed a high prevalence of minor oro-surgery procedures in our population, while its role in PIFP pathophysiology remains unknown. A new classification of PIFP built around the main discriminant factor of presence of these procedures in the painful area could be considered while available data were still insufficient to define specific diagnostic criteria.

Background: Fibromyalgia Syndrome (FMS) is characterized by chronic widespread pain, fatigue, unrefreshing sleep and cognitive dysfunction. Depressive and manic symptoms are often reported in FMS patients’ history. The aim of this study was to evaluate the prevalence of bipolar spectrum symptoms (BSS) and to correlate these with quality of life (QoL) scores and antidepressant treatment. Methods: From October 2017 to July 2018, a battery of QoL questionnaires (FIQ, PSQI and SF-12) was administered to 120 FMS patients after a clinical examination. The MOODS-SR lifetime questionnaire was then remotely administered to the patients included in the study. Results: The presence of depressive and manic lifetime symptoms was found, in line with the results of the available literature. A correlation was found between the history of depressive symptoms and the severity of FIQ and SF-12 scores. Despite a low statistical strength, a trend toward a correlation between a history of manic symptoms and SNRI treatment was detected. Conclusions: The correlation between the MOOD—depressive domains and poor QoL is in line with the available literature. Further studies are needed to corroborate these findings and to elucidate the relationship between manic symptoms and SNRI treatment.

Chronic low back pain (CLBP) due to osteoarthritis represents a therapeutic challenge worldwide. Opioids are extensively used to treat such pain, but the development of tolerance, i.e., less susceptibility to the effects of the opioid, which can result in a need for higher doses to achieve the same analgesic effect, may limit their use. Animal models suggest that ultra-low doses of opioid antagonists combined with opioid agonists can decrease or block the development of opioid tolerance. In this retrospective study, we tested this hypothesis in humans. In 2019, 53 patients suffering from CLBP were treated with either Oxycodone and Naloxone Prolonged Release (27 patients, OXN patients) or Oxycodone Controlled Release (26 patients, OXY patients). The follow-up period lasted 2 years, during which 10 patients discontinued the treatment, 5 out of each group. The remaining 43 patients reached and maintained the targeted pain relief, but at 18 and 24 months, the OXY patients showed a significantly higher oxycodone consumption than OXN patients to reach the same level of pain relief. No cases of respiratory depression or opioid abuse were reported. There were no significant differences in the incidence of adverse effects between the two treatments, except for constipation, more common in OXY patients. From our results, we can affirm that a long-term opioid treatment with oxycodone-naloxone combination, when compared with oxycodone only, may significantly hinder the development of opioid tolerance. We were also able to confirm, in our cohort, the well known positive effect of naloxone in terms of opioid-induced bowel dysfunction incidence reduction.

Fibromyalgia syndrome (FMS) is a chronic condition characterized by widespread musculoskeletal pain, fatigue, cognitive impairments, and sleep disturbances. Although traditionally considered psychogenic, recent research supports a multifactorial etiology involving central nervous system (CNS) dysregulation and significant immune involvement. This narrative review synthesizes current evidence regarding the role of immune mechanisms in FMS, with comparative insights into chronic fatigue syndrome/myalgic encephalomyelitis (CFS/ME) and irritable bowel syndrome (IBS)—previously grouped under functional somatic syndromes (FSS). In FMS, immune dysregulation is evidenced by elevated levels of pro-inflammatory cytokines (e.g., IL-6, IL-8, TNF-α) and decreased anti-inflammatory mediators such as IL-10, contributing to symptomatology including pain amplification and fatigue. Neuroinflammation, as indicated by microglial activation in pain-processing CNS regions, further supports the role of immune signaling in central sensitization. Other contributing factors include oxidative stress, mitochondrial dysfunction, and immune cell alterations, particularly involving regulatory T cells and natural killer (NK) cells. Compared to FMS, CFS/ME exhibits greater systemic immune activation and more severe mitochondrial impairment, correlating with profound fatigue and cognitive decline. IBS, on the other hand, shows immune activation localized to the gastrointestinal tract, emphasizing the gut-brain axis. These findings highlight both shared and syndrome-specific immune features. To better reflect their systemic and immunological complexity, this review refers to these conditions collectively as chronic multisystem immune-related disorders (CMIRDs). The evidence supports the development of biomarker-based diagnostics and personalized immunomodulatory therapies. A multidisciplinary approach that integrates immunology and neurology is essential to improve outcomes for patients with FMS and related disorders.

Background and Objectives: Fibromyalgia syndrome (FMS) is a multifaceted disease with a strong preference for the female sex. It is characterised by chronic widespread pain, sleep–wake disorders, fatigue, cognitive disturbances, and several other somatic symptoms. Materials and Methods: In this prospective observational study, we analysed data regarding 302 patients who were referred to our pain centre for a first clinical assessment evaluation and were then inspected for the physician-based 2016 revision of the ACR diagnostic criteria for FMS, regardless of the final diagnosis previously made by the pain therapist. Results: Among the 280 patients who adhered to the 2016 ACR questionnaire, 20.3% displayed positive criteria for FMS diagnosis. The level of agreement between the FMS discharge diagnosis made by the pain clinician and the ACR 2016 criteria-positivity was moderate (kappa = 0.599, with moderate agreement set at a kappa value of 0.6). Only four patients (1.7%) diagnosed as suffering from FMS at discharge did not satisfy the minimal 2016 ACR diagnostic criteria. Conclusions: This prospective observational study confirmed the diagnostic challenge with FMS, as demonstrated by the moderate grade of agreement between the FMS diagnosis at discharge and the positivity for 2016 ACR criteria. In our opinion, the use of widely accepted diagnostic guidelines should be implemented in clinical scenarios and should become a common language among clinicians who evaluate and treat patients reporting widespread pain and FMS-suggestive symptoms. Further methodologically stronger studies will be necessary to validate our observation.