Clinical Pearls & Morning Reports
Published June 19, 2019
For the management of acute pain, the use of multiple approaches that do not include opioids and the establishment of acute pain services for postoperative pain management can reduce opioid-related adverse effects and dependence. Read the Review Article here.
Q: Is the capsaicin 8% patch a first-line treatment for postherpetic neuralgia?
A: The capsaicin 8% patch is a second-line treatment for peripheral neuropathic pain such as postherpetic neuralgia and painful polyneuropathy, but there is no evidence of effectiveness in other pain conditions.
Q: Oxcarbazepine and carbamazepine are first-line treatments for what types of neuropathic pain?
A: Oxcarbazepine and carbamazepine are first-line treatments for trigeminal neuralgia, and the rate of success with these agents in treating this disorder has been considered to be good. For other types of neuropathic pain, there is inconclusive evidence for the use of these drugs.
A: Tricyclic antidepressants and serotonin-norepinephrine (noradrenaline) reuptake inhibitors have been used as first-line treatments for neuropathic pain, defined as pain due to a lesion or disease of the peripheral or central somatosensory nervous system. Antidepressants have also been recommended for prophylactic treatment of migraine and tension-type headache. There is some evidence of an analgesic effect of these drugs on pain from fibromyalgia, although it has been suggested that the benefits are outweighed by side effects in most patients. Systematic review of studies involving patients with low back pain suggests no overall effect of antidepressants on pain intensity or function, except for a small effect of duloxetine (a reduction in pain of <1 point on a scale of 0 to 10). The question of whether certain antidepressants have advantages over others is not settled. Amitriptyline is the tricyclic antidepressant with the best-documented analgesic effects, but desipramine, nortriptyline, and imipramine are likely to have less pronounced anticholinergic and sedative side effects and are associated with a lower risk of falls.
A: Several drugs used for the treatment of epilepsy have apparent analgesic properties through their putative effects of lowering neurotransmitter release or reducing neuronal firing. Gabapentin and pregabalin are recommended in guidelines for the treatment of neuropathic pain, and pregabalin has also been shown to be effective in trials for pain from fibromyalgia, with modest adverse events. Not all trials show the superiority of antiepileptic agents over placebo, and a recent trial failed to show an effect of pregabalin in patients with sciatica. Side effects such as sedation and dizziness are common with both gabapentin and pregabalin, and there is increasing evidence of misuse and abuse of these drugs. Pregabalin is approved by the FDA only for neuropathic pain and pain from fibromyalgia; evidence of an effect on pain from other conditions is lacking, and concern has been expressed about increasing off-label use.