Response Profiles to High-concentration Capsaicin Desensitization in Patients With Peripheral Neuropathic...
Peripheral Neuropathic PainProspective multicenter cohort to determine patient profiles (associated factors, including allodynia) with a better response to pain desensitization by capsaicin delivered in the form of a high concentration patch (8%), in a population of patients with peripheral neuropathic pain and followed up in a pain consultation in the Auvergne Rhône Alpes region.
L-menthol as a Topical Counter-irritant to TRPA1-induced Neurogenic Inflammation and Pain
InflammationPruritus1 moreThe aim of this study is to quantitatively characterize the effects of L-menthol as a topical counter-irritant on cutaneous pain and hyperalgesia provoked by topical application of the TRPA1-agonist trans-cinnamaldehyde (CA) in healthy human volunteers.
An fMRI Study in Healthy Volunteers to Investigate the Effects of ABX-1431 on Experimental Hyperalgesia...
PainAn fMRI study in healthy volunteers to investigate the effects of ABX-1431 on experimental hyperalgesia and its neural correlates.
Pain Response to Cannabidiol in Induced Acute Nociceptive Pain, Allodynia and Hyperalgesia By Using...
Pain SensationHyperalgesia1 moreThis study is to investigate the effect of CBD on acute pain in healthy volunteers in a well-established acute pain model.
Analgesic Effect of Oxytocin Receptor Modulation
PainHyperalgesia1 moreCarbetocin is a synthetic analogue of the hormone Oxytocin and is routinely used in obstetric anesthesiology to control uterine bleeding after cesarean section. As an incidental finding, women who received carbetocin had less pain after cesarean section than women who had received Oxytocin. Carbetocin may therefore have an analgesic effect. The present study examines this analgesic effect using different sensory tests, e.g. pressure, heat, cold and electrical pain before and after administration of carbetocin in healthy male volunteers. Any changes in these sensory tests might be indicative of an analgesic property of carbetocin.
Mechanisms of Sleep Disruption Hyperalgesia
Sleep DeprivationPainTwenty percent of Americans suffer from chronic pain. Sleep disturbance is similarly prevalent and among the most common and disabling neurobehavioral problems associated with chronic pain. This research is designed to evaluate the effects of disrupted sleep patterns on mood, inflammation, the perception of pain, and pain relief. This study will help researchers understand the relationship between sleep and pain, and how sleep disturbance might influence chronic pain conditions.
Pain-related Fear as a Facilitator of Nocebo Hyperalgesia
HyperalgesiaChronic Pain Syndrome3 moreNocebo hyperalgesia is characterized by adverse pain outcomes, induced by patients' expectations. In the lab, nocebo effects are commonly studied via classical conditioning, a method that employs pairings of neutral cues/treatments with different pain intensities to install differential pain-related expectations. In such conditioning experiments, participants are typically taught that a (sham) treatment exaggerates their pain, by surreptitiously administering high intensity (e.g. pain) stimuli in combination with this treatment. Verbal suggestions are also often used to inform participants of the supposed adverse effects of such treatments. In nocebo studies, higher pain levels and suggestions that are of more threatening nature may induce fear, thereby adding a crucial element to the experimental manipulation. Since nocebo effects are hypothesized to arise in clinical settings due to a combination of several psychological and cognitive mechanisms, it is important to study the role that factors such as higher pain levels, conditioned pain-related fear, or more threatening verbal suggestions may play in the formation of nocebo hyperalgesia. To date, no studies have focused on the fear-inducing effect that different pain intensities or verbal threat suggestions may have and how this fear, in turn, may strengthen the acquisition of nocebo effects. This study aims to investigate whether higher pain intensity or higher pain-related fear induced via threatening suggestions facilitate the acquisition and hinder subsequent extinction of nocebo hyperalgesia. This study will be conducted at Leiden University.
Effect of High-dose Target-controlled Naloxone Infusion on Pain and Hyperalgesia During a Burn Injury...
Healthy SubjectsIn several rodent studies, it has been demonstrated that very high doses of opioid antagonists (i.e., naloxone 3-10 mg/kg) administered after weeks after recovery from an inflammatory injury may lead to a reinstatement of hyperalgesia and pain behavior. This latent sensitization has recently been demonstrated also to take place in humans. The present study examines if it is possible to foresee individuals who will demonstrate a larger degree of latent sensitization upon challenge with an injury, than others. Using an enriched design high sensitizers (e.g., the upper quartile of individuals developing large areas of secondary hyperalgesia following a mild burn injury) are compared with low sensitizers (lower quartile), regarding the propensity for developing latent sensitization
Fenobam on Heat/Capsaicin Induced Hyperalgesia in Healthy Volunteers
HyperalgesiaAllodyniaOur goal is to demonstrate that healthy volunteers treated with fenobam will develop a significantly reduced area of cutaneous hyperalgesia compared to volunteers treated with placebo, after exposure to the heat/capsaicin model of cutaneous sensitization. Additionally we are going to assess changes in mood/affect and cognitive function of subjects following administration of fenobam and after cutaneous sensitization compared to baseline.
Effects of Milnacipran on Widespread Mechanical and Thermal Hyperalgesia of Fibromyalgia Patients...
FibromyalgiaFibromyalgia syndrome (FM) shares many symptoms common to chronic neuropathic pain, including the characteristic hyperalgesia of the skin (thermal, mechanical) and muscles (mechanical) found in almost all FM patients. Milnacipran, a balance norepinephrine-serotonin re-uptake inhibitor, has been found to reduce pain and improve physical function of FM patients. However, little is known about the pain mechanisms that are affected by this medication. Therefore, the investigator wants to determine the efficacy of milnacipran in reducing pain as well as mechanical and thermal hyperalgesia of FM patients during a randomized, double-blind, placebo controlled trial. Because the investigator expects anti-hyperalgesic effects to coincide or precede with effects on clinical FM pain the proposed duration for this trial is 6 weeks.