View clinical trials related to Hyperalgesia.
Filter by:This study is to investigate the effect of CBD on acute pain in healthy volunteers in a well-established acute pain model.
This study is designed to evaluate the method of assessing the and intensity areas of secondary hyperalgesia induced by High Frequency Stimulation (HFS). Measures of the areas of secondary hyperalgesia will take place on two experimental days separated by a minimum of two weeks. Each experimental day, the areas of secondary hyperalgesia will be assessed three times, starting 30 minutes following HFS. Furthermore, the investigators will assess if anxiety, catastrophization, stress and demographic variables modulate the extend of hyperalgesia.
Pain is defined as an unpleasant sensory and emotional conscious experience, associated with actual or potential tissue damage. Nociception is the sympathetic response to noxious stimuli during unconsciousness. The appearance of different forms of chronic pain results from sensitization of both peripheral and central neural circuits of pain, which involves inflammatory mechanisms both at a systemic level and specifically in the peripheric and central nervous system, as observed through elevation of specific neuroinflammatory mediators, such as MCP-1, IL-1, IL-1b, and IL-10. Clinically, this sensitization expresses as hyperalgesia and allodynia, which increase postoperative pain and morbidity, but also induce permanent modifications in the nociceptive system. These effects may be ameliorated by adequately adjusting intraoperative analgesia through use of nociception/analgesia balance monitors, of which Nociception Level Index (NOL) shows convenient characteristics and promising results from previous studies. Objectives: The goal of our study is to assess the utility of NOL index monitoring against standard care for Fentanyl-based analgesia by measuring postoperative pain, sensorial thresholds and inflammatory markers related to nociception. Hypothesis: The use of NOL index to guide the intraoperative analgesia will produce less postoperative pain, hyperalgesia, allodynia, and neuroinflammation.
To evaluate the effect of oral gabapentin premedication on hyperalgesia in elderly patients undergoing staged bilateral cataract operations under monitored anesthesia care
Nocebo effects are adverse effects induced by patients' expectations. Nocebo effects on pain may underlie several clinical conditions, such as chronic pain. These effects can be learned via classical conditioning mechanisms. In the lab, nocebo effects are commonly studied via conditioning with continuous reinforcement (CRF) during which 100 percent of unconditioned pain stimuli are paired to conditioned stimuli (i.e., the activation of a mock medical device). Partial reinforcement (PRF) provides a more uncertain pairing during conditioning, where less than 100 percent of unconditioned pain stimuli are paired to conditioned stimuli. This method provides a potentially more clinically relevant learning platform to study how nocebo effects on pain are induced. In this study, the efficacy of conditioning with PRF, CRF, and sham-conditioning in inducing nocebo effects on pain will be compared. Furthermore, a counterconditioning method will be compared to an extinction method for the attenuation of nocebo effects on pain. Given the relevance of nocebo effects for patients, it is important to ascertain effective & clinically relevant methods to understand how nocebo effects may be formed and attenuated. This study is conducted by Leiden University.
The majority of migraineurs seeking secondary or tertiary medical care develop cutaneous allodynia during the course of migraine, a sensory abnormality mediated by sensitization of central trigeminovascular neurons in the spinal trigeminal nucleus. Triptan therapy can render allodynic migraineurs pain-free within a narrow window of time (20-120 min) that opens with the onset of pain and closes with the establishment of central sensitization. This calls for the development of drugs that can tackle ongoing central sensitization and render allodynic migraineurs pain-free after the window for triptan therapy has expired. There are two main objectives the investigators seek to achieve from this study: to determine whether oral administration of DFN-15 (solution of a COX2 inhibitor, Celecoxib) terminates migraine attacks when given to allodynic participants 3 hours after attack onset; and to determine whether mechanical and heat allodynia that develop during acute migraine attacks could be reversed by late (> 3hrs after attack onset) treatment with DFN-15. Participants will be recruited from the Headache Center and randomized in a double-blinded fashion to receive either the active drug (DFN-15) or placebo in a ratio of 4:1.The participants will be instructed to return to the clinic during a migraine. At the 'during-migraine' visit, which will begin 3 hours after onset of headache, the investigators will document headache intensity, associated symptoms, and mechanical and heat pain threshold (first) before treatment (at 180 min after onset of headache) and (second) at a 120 min after treatment (5 hours after headache onset). Based on our prior experience studying migraine patients, the investigators plan to screen 100 patients to achieve 50 participants completing the 2 study visits as planned. The active drug group will consist of 80/100 patients and 20/100 patients will receive the placebo. The study will be terminated as soon as the first 40 participants who received the DFN-15 and first 10 patients who received placebo completed visit 2.
The purpose of this study is to investigate pain evoked responses and facilitation of NGF-induced mechanical muscle hyperalgesia over time following an acute exercised-induced ischemic condition in a NGF-sensitized muscle.
Randomized, double-blinded, three arm study in adult patients undergoing first time coronary artery bypass grafting (CABG) surgery with median sternotomy. The investigators will examine the effects of three fentanyl dosing schemes (high-dose bolus, low-dose bolus, continuous dose) on the area of hyperalgesia and allodynia at 24 and 48h as well as on persisting pain at 3, 6, and 12 months. Additionally, the investigators will measure fentanyl concentrations throughout anesthesia.
The purpose of this study is to investigate the sensory-motor cortical excitability response to delayed onset muscle soreness (DOMS) on Extensor Carpi Radialis (ECR) muscle during muscle hyperalgesia provoked by nerve growth factor (NGF).
The purpose of this study is to investigate and determine the time course and distribution on muscle hyperalgesia and muscle pain in a repeated, low dose NGF model. It is hypothesized that low dosages i.m injections of NGF are able to induce mechanical hyperalgesia and muscle soreness in a same manner (effect of duration) as for dosages previously used in NGF studies. Furthermore, it is also speculated if several injections of low dose NGF into the muscle combined are able to course immediate pain sensation and spreading of muscle hypersensitivity.