Pain
-
Some expert guidelines recommend time-scheduled opioid dosing over pain-contingent dosing for patients receiving chronic opioid therapy (COT). The premise is that time-scheduled dosing results in more stable opioid blood levels and better pain relief, fewer adverse effects, less reinforcement of pain behaviors, and lower addiction risk. We report results of a survey of 1781 patients receiving COT for chronic noncancer pain, in which 967 reported time-scheduled opioid dosing only and 325 reported pain-contingent opioid dosing only. ⋯ Controlled comparative effectiveness research is needed to assess benefits and risks of time-scheduled opioid dosing relative to pain-contingent opioid dosing among COT patients in ambulatory care. Patients with time-scheduled dosing received higher opioid dosage than patients with pain-contingent dosing. Time-scheduled dosing was associated with greater opioid control concerns than pain-contingent dosing.
-
Opioid receptors are major actors in pain control and are broadly distributed throughout the nervous system. A major challenge in pain research is the identification of key opioid receptor populations within nociceptive pathways, which control physiological and pathological pain. In particular, the respective contribution of peripheral vs. central receptors remains unclear, and it has not been addressed by genetic approaches. ⋯ Delta receptors in these neurons tonically inhibit mechanical hypersensitivity in both inflammatory and neuropathic pain, and they are essential to mediate delta opioid analgesia under conditions of persistent pain. This delta receptor population represents a feasible therapeutic target to alleviate chronic pain while avoiding adverse central effects. The conditional knockout of delta-opioid receptor in primary afferent Na(V)1.8 neurons augmented mechanical allodynia in persistent pain models and abolished delta opioid analgesia in these models.
-
The ability to determine precisely the location of sensory stimuli is fundamental to how we interact with the world; indeed, to our survival. Crossing the hands over the body midline impairs this ability to localize tactile stimuli. We hypothesized that crossing the arms would modulate the intensity of pain evoked by noxious stimulation of the hand. ⋯ Besides studies showing relief of phantom limb pain using mirrors, this is the first evidence that impeding the processes by which the brain localises a noxious stimulus can reduce pain, and that this effect reflects modulation of multimodal neural activities. By showing that the neural mechanisms by which pain emerges from nociception represent a possible target for analgesia, we raise the possibility of novel approaches to the treatment of painful clinical conditions. Crossing the arms over the midline impairs multimodal processing of somatosensory stimuli and induces significant analgesia to noxious hand stimulation.
-
Excessive medication intake is a risk factor for the development of medication-overuse headache (MOH), a condition characterized by an increase of headache frequency to a daily or near-daily pattern. As yet, it is largely unknown why some patients overuse medication. In this study, we examined to what extent attitudes about pain medication, especially perceived need and concerns, and problem-solving are related to MOH. ⋯ Results are discussed in terms of how repeated attempts to solve pain may trigger overuse of medication, even in the presence of clear negative consequences. Repeated attempts at solving pain may increase the need for analgesic medication, despite obvious costs. This mechanism might contribute to the problem of medication-overuse headache.