Articles: neuralgia.
-
Randomized Controlled Trial Clinical Trial
Effect of adrenergic receptor activation on post-herpetic neuralgia pain and sensory disturbances.
Patients with acute herpes zoster, and to a lesser extent post-herpetic neuralgia (PHN), have been reported to respond to local anesthetic blockade of the sympathetic nervous system. In animal models of nerve injury, local injection of adrenergic agonists after nerve injury, but not before, excites nociceptors. In some patients with chronic neuropathic pain, local application of norepinephrine evokes pain. ⋯ After injection of the adrenergic agonist into PHN skin, both overall PHN pain and allodynia severity were significantly greater than after saline injection, peaking at 10-15 min post-injection. Even when PHN has been present for years, adrenergic receptor stimulation in PHN skin increases pain, most likely through direct activation of C-nociceptors in the painful skin. Increased allodynia is most likely mediated centrally and driven by the increase in C-nociceptor input.
-
J Pain Symptom Manage · Sep 1996
Randomized Controlled Trial Clinical TrialResponse to intravenous lidocaine infusion predicts subsequent response to oral mexiletine: a prospective study.
The local anesthetic sodium-channel blockers lidocaine and mexiletine reduce spontaneous and evoked activity in experimental neuroma models and have been reported to relieve a variety of clinical neuropathic pain conditions. The predictive value of relief from an intravenous lidocaine infusion (IVL) for subsequent relief from a 4-week trial of oral mexiletine was assessed in a prospective study of nine subjects with chronic neuropathic pain of peripheral origin. Subjects received IVL, 2 mg/kg and 5 mg/kg, over 45 min during separate sessions in random order under double-blind conditions. ⋯ Subsequent response to oral mexiletine was significantly correlated with the average response to the two IVL. Mexiletine dose and blood levels were not correlated with pain relief. The results suggest that IVL may be a valuable tool in selecting patients for oral therapy with analogous drugs.
-
Randomized Controlled Trial Clinical Trial
Lidocaine patch: double-blind controlled study of a new treatment method for post-herpetic neuralgia.
Post-herpetic neuralgia (PHN) is a common and often intractable neuropathic pain syndrome predominantly affecting the elderly. Topical local anesthetics have shown promise in both uncontrolled and controlled studies. Thirty-five subjects with established PHN affecting the torso or extremities completed a four-session, random order, double-blind, vehicle-controlled study of the analgesic effects of topically applied 5% lidocaine in the form of a non-woven polyethylene adhesive patch. ⋯ The highest blood lidocaine level measured was 0.1 micrograms/ml, indicating minimal systemic absorption of lidocaine. Patch application was without systemic side effect and well tolerated when applied on allodynic skin for 12 h. This study demonstrates that topical 5% lidocaine in patch form is easy to use and relieves post-herpetic neuralgia.
-
Anesthesia and analgesia · Oct 1995
Randomized Controlled Trial Clinical TrialSystemic adenosine infusion alleviates spontaneous and stimulus evoked pain in patients with peripheral neuropathic pain.
In seven patients with peripheral neuropathic pain, the effect of systemic adenosine infusion on pain symptoms was evaluated in a double-blind, placebo controlled, cross-over study. The study infusions, adenosine (50 micrograms.kg-1.min-1) or placebo, were given intravenously (IV) during 45-60 min at two separate occasions. Before and during infusions, bedside examination of sensibility and quantitative sensory testing (QST), i.e., assessments of perception thresholds for touch, touch-evoked pain, cold, warmth, painful heat, and cold, were performed. ⋯ Pinprick-evoked pain in the neuropathic areas was reduced from 53 +/- 11 to 29 +/- 10 mm (P < 0.05). No other sensory modality was consistently changed during adenosine infusion. In conclusion, the present study demonstrates that adenosine infusion alleviates spontaneous neuropathic pain, tactile allodynia, and pinprick hyperalgesia in patients with peripheral neuropathic disorders, probably by a central mechanism of action.
-
Randomized Controlled Trial Clinical Trial
Double-blind, placebo-controlled study of the application of capsaicin cream in chronic distal painful polyneuropathy.
We have completed a 12-week double-blind, placebo-controlled randomized study on the efficacy of the application of capsaicin (CAPS) cream (0.075%) in the treatment of chronic distal painful polyneuropathy. Forty patients were enrolled and 39 completed the study. The 2 limbs were randomly assigned to CAPS or placebo (PLAC). ⋯ All the safety indices showed no difference between sides. We interpret the early hyperalgesia on the CAPS side as being responsible for the better performance of PLAC at early time points. The large percentage of limbs that improved may be a pronounced PLAC response.