Herpes zoster is an acute, self-limited disease of infectious origin. It is characterized by grouped vesicular lesions on an erythematous base distributed over several dermatomes as well as single. In some cases the patients can be found to have an identifiable risk factor such as old age, malignancy, irradiation, chemotherapy, immunosuppresive therapy and trauma. The majority of cases are self-limited and resolved completely. However it may have serious complication. We reviewed 369 cases of herpes zoster to determine the distribution of lesions, incidence of postherpetic neuralgia, associated disorders, and the age. 134 cases (36.1%) of 369 cases with herpes zoster were associated with chronic disorders. The complications of herpes zoster were developed in 71 cases (19.2%) and postherpetic neuralgia (PHN) was the most commom complication. The frequency and severity of postherpetic neuralgia were proportional to age. There was a predilection of the involvement in thoracic dermatomes, lumbar dermatomes and ophthalmic division of trigeminal nerve in decreasing order of frequency. The incidence and duration of postherpetic neuralgia are significantly related to age.
Drug Therapy ; Herpes Zoster* ; Humans ; Incidence ; Neuralgia, Postherpetic ; Risk Factors ; Trigeminal Nerve

Neuropathic pain is a common and very prevalent disorder affecting the citizens of both developed and developing countries. The approved and licensed drugs for neuropathic pain are reported to have associated side effects. Traditional plant treatments have been used throughout the world for the treatment of neuropathic pain. Among the many medications and other alternative medicines, several herbs are known to cure and control neuropathic pain with no side effects. The present paper discusses the plants with neuropathic pain and related beneficial effects originating from different parts of world that are of current interest.
Animals ; Humans ; Neuralgia ; drug therapy ; Phytotherapy ; Plant Extracts ; therapeutic use ; Plants, Medicinal ; chemistry

Activation of microglia plays a vital role in the initiation and maintenance of specific neuropathic pain states. By activating microglia in central nervous system, Toll-like receptor 4 (TLR4) can promote the release of proinflammatory cytokines and neuroactive compounds, participate in the initiation and maintenance of neuropathic pain, and trigger the opiate side effects. Therefore, TLR4 may be a potential therapeutic target for neuropathic pain. Inhibition of TLR4 has shown some biological effects in neuropathic pain models and ibudilast (the TLR4 pathway-inhibiting agent) has been approved for for phase 2 clinical trials. This article briefly reviews the structure, function, and mechanism of TLR4 as well as the development of TLR4-targeted drugs.
Humans ; Neuralgia ; drug therapy ; physiopathology ; Toll-Like Receptor 4 ; antagonists & inhibitors ; physiology

OBJECTIVE: To determine the short and mid-term effect of paravertebral adriamycin injection under CT guidance on intractable postherpetic neuralgia (PHN). METHODS: From January 2010 to May 2012, 68 patients with intractable PHN receiving paravertebral adriamycin injection under CT guidance were enrolled. The outcome included the Quality of Life Score (QLS), Visual Analogue Score (VAS) (average, the worst and the least VAS), pain relief rate at the time before and after the injection, and 1 year after discharge. RESULTS: Lower VAS was observed after the injection than that before the injection [(3.5 ± 1.5) vs (7.9 ± 1.3) on average; (2.1 ± 0.9) vs (6.5 ± 1.7) at least and (4.5 ± 1.4) vs (9.2 ± 1.1) at worst, P<0.05]. Lower VAS at 1 year after discharge was found than that before the injection [(2.2 ± 1.8) vs (7.9 ± 1.3) on average; (1.5 ± 0.8) vs (6.5 ± 1.7) at least; (3.2 ± 1.6) vs (9.2 ± 1.1) at worst ] and that after the injection [(3.5 ± 1.5) vs (2.2 ± 1.8) on average; (1.5 ± 0.8) vs (2.1 ± 0.9) at least and (3.2 ± 1.6) vs (4.5 ± 1.4) at worst, P<0.05]. The pain relief rate after the injection was (68 ± 23)%. The pain relief rate at 1 year after discharge (81 ± 22)% was higher than that at discharge (68 ± 23)% (P<0.05). The quality of life evaluation index scale after the injection (daily life, diet, general activities, sleep, work and social activities) was significantly improved than that before the injection [(10.1 ± 2.2) vs (14.2 ± 1.9), P<0.05]. The quality of life evaluation index scale at 1 year after discharge was significantly improved than that before the injection [(7.0 ± 2.1) vs (14.2 ± 1.9)] and that after the injection [(7.0 ± 2.1) vs (10.1 ± 2.2), P<0.05]. No complication was observed when the patients were discharged and 1 year after discharge. CONCLUSION Paravertebral adriamycin injection under CT guidance for intractable PHN can effectively relieve the patient's pain, improve the quality of sleep and life without obvious complications. It is safe and effective for intractable PHN.
Doxorubicin ; administration & dosage ; therapeutic use ; Humans ; Neuralgia, Postherpetic ; drug therapy ; Pain Measurement ; Quality of Life

Objective To observe the changes of brain function in patients with trigeminal neuralgia after administration of flurbiprofen axetil by using the resting-state functional magnetic resonance imaging(fMRI)and based on the amplitude of low-frequency fluctuation(ALFF). Methods Resting fMRI data of 20 patients with trigeminal neuralgia before and after treatment with flurbiprofen axetil were collected by 1.5T magnetic resonance imaging system.The resting fMRI data were pretreated by Statistical Parametric Mapping and DPABI(a toolbox for Data Processing and Analysis for Brain Imaging)software,and the difference of low-frequency oscillation amplitude of brain spontaneous activity before and after treatment with flurbiprofen axetil was analyzed by ALFF. Results The Visual Analogue Scale of pain intensity after flurbiprofen axetil injection was significantly lower than that before administration,and the pain relieved significantly(P=0.000).The ALFF values of right dorsolateral prefrontal lobe,bilateral medial prefrontal lobe,and right middle cingulate gyrus in patients treated with flurbiprofen axetil at rest were significantly lower than those before administration(P=0.000). Conclusions The analgesic effect of flurbiprofen axetil is exerted on the central system.This agent can inhibit the abnormal brain function caused by chronic pain stimulation and thus reduce pain.However,the specific mechanism needs further investigations.
Brain ; drug effects ; Brain Mapping ; Flurbiprofen ; analogs & derivatives ; pharmacology ; Humans ; Magnetic Resonance Imaging ; Trigeminal Neuralgia ; drug therapy

OBJECTIVETo investigate the effect of L-838,417 on the results of behavioral test in rats with experimentally induced trigeminal neuralgia.

METHODSMale SD rats were randomized into model group (n=34), sham-operated group (n=30) and control group (n=6). Thirty rats with trigeminal neuralgia induced by chronic constriction injury of the infraorbital nerve below the zygomatic bone were randomly divided into 5 equal groups for treatment with 1.0 mg/kg L-838,417 (L1 group), 10.0 mg/kg L-838,417 (L10 group), 5 mg/kg morphine (M group), 3 mg/kg diazepam (D group), or normal saline (NS group). The pain threshold of the tentacles pad to von-Frey filament stimulation was measured in the rats before and at 1, 2, 3, 4, 5 h after the treatments. The sedative effect of L-838,417 was evaluated by recording the position scores and righting reflex scores, and the drug tolerance was also evaluated.

RESULTSNine days after the operation, the pain threshold of the rats in the model group was significantly decreased compared with that before operation and that of the sham group (P<0.01). The threshold of L1 and L10 groups were both significantly increased 1 h after L-838,417 administration (P<0.01). The rats in the NS, L1, and L10 groups did not show unusual posture or righting reflex. In L1 and L10 groups, L838,417 did not show attenuated efficacy after prolonged use (10 days).

CONCLUSIONL-838,417 can effectively improve hyperalgesia in rats with trigeminal neuralgia without causing sedation, motor impairment, or drug tolerance.

Animals ; Fluorobenzenes ; pharmacology ; Hyperalgesia ; drug therapy ; Male ; Pain Measurement ; Pain Threshold ; drug effects ; Rats ; Rats, Sprague-Dawley ; Triazoles ; pharmacology ; Trigeminal Neuralgia ; drug therapy ; physiopathology

Neuropathic cancer pain (NCP) is caused by nerve damage attributable to the cancer per se, and/or treatments including chemotherapy, radiotherapy, and surgery; the prevalence is reported to be as high as 40%. The etiologies of NCP include direct nerve invasion or nerve compression by the cancer, neural toxicity, chemotherapy, and radiotherapy. NCP is subdivided into plexopathy, radiculopathy, and peripheral neuropathies, among several other categories. The clinical characteristics of NCP differ from those of nociceptive pain in terms of both the hypersensitivity symptoms (burning, tingling, and an electrical sensation) and the hyposensitivity symptoms (numbness and muscle weakness). Recovery requires several months to years, even after recovery from injury. Management is complex; NCP does not usually respond to opioids, although treatments may feature both opioids and adjuvant drugs including antidepressants, anticonvulsants, and anti-arrhythmic agents, all of which improve the quality-of-life. This review addresses the pathophysiology, clinical characteristics and management of NCP, and factors rendering pain control difficult.
Analgesics, Opioid ; Anticonvulsants ; Antidepressive Agents ; Drug Therapy ; Hypersensitivity ; Neuralgia ; Nociceptive Pain ; Peripheral Nervous System Diseases ; Prevalence* ; Radiculopathy ; Radiotherapy

Trigeminal neuralgia (TN) is a kind of recurrent transient and severe pain that is limited to the trigeminal nerve in one or more branches. The clinical incidence of TN is high, which seriously affects the quality of life of the patients and is difficult to cure. The present study investigated the effects of tetramethylpyrazine (TMP) on TN induced by chronic constriction injury of the infraorbital nerve (ION-CCI) in rats. Adult male Sprague-Dawley rats were randomly assigned to four groups: sham, sham treated with TMP (Sham+TMP), TN model (TN), and TN treated with TMP (TN+TMP). The rat TN model was established by ION-CCI and TMP (50 mg/kg) was injected intraperitoneally once a day for 2 weeks after operation. The mechanical response threshold was tested by the electronic von Frey filaments. The expression of CGRP in the trigeminal ganglia (TGs) of rats on the operative side was detected by RT-PCR, immunohistochemical staining and Western blot. In 15 days after operation, TN group showed a robust decrease in mechanical response threshold as compared with sham group. From day 9 to day 15 after operation, TMP treatment significantly suppressed the TN-induced mechanical hyperalgesia (P < 0.05). On day 15 after operation, RT-PCR, immunohistochemical staining and Western blot analysis showed an obvious increase in expression level of CGRP in TGs of TN group compared with sham group, which was downregulated by TMP treatment (P < 0.05). These results suggested that TMP might have a therapeutic potential for the treatment of TN through regulating CGRP expression in the TGs.
Animals ; Constriction ; Hyperalgesia ; drug therapy ; Male ; Pyrazines ; pharmacology ; Random Allocation ; Rats ; Rats, Sprague-Dawley ; Trigeminal Ganglion ; physiopathology ; Trigeminal Neuralgia ; drug therapy

OBJECTIVE: To investigate the mechanisms underlying elemene-induced analgesia in rats with spared nerve injury (SNI). METHODS: Sixty-five rats were equally divided into 5 groups using a random number table: naive group, sham group, SNI group, SNI + elemene (40 mg·kg RESULTS: The SNI rat model exhibited a significant decrease in paw withdrawal threshold and exploratory behaviour in the EPM (P<0.05). Consecutive administration of elemene alleviated SNI-induced mechanical allodynia and anxiety in rats (P<0.05). Immunohistochemical data showed that elemene decreased SNI-induced upregulation of NDRG2 within the SDH (P<0.05). Double immunofluorescent staining data further showed that elemene decreased SNI-induced upregulation of the number of GFAP immunoreactive (-ir), NDRG-ir, and GFAP/NDRG2 double-labelled cells within the SDH (P<0.05). Immunoblotting data showed that elemene decreased SNI-induced upregulation of GFAP and NDRG2 within the SDH (P<0.05). CONCLUSION Elemene possibly alleviated neuropathic pain by downregulating the expression of NDRG2 in spinal astrocytes in a rat model of SNI.
Animals ; Astrocytes ; Disease Models, Animal ; Emulsions ; Hyperalgesia/drug therapy* ; Nerve Tissue Proteins ; Neuralgia/drug therapy* ; Rats ; Rats, Sprague-Dawley ; Sesquiterpenes ; Spinal Cord ; Spinal Cord Dorsal Horn

OBJECTIVE: To investigate the effect of escin in relieving chemotherapy-induced peripheral neuropathic pain in rats and explore and the underlying mechanism. METHODS: Eighteen SD rats were randomly divided into 3 groups ( RESULTS: The rats in both the escin preconditioning group and escin postconditioning group showed obviously increased thresholds of mechanical allodynia and thermal hyperalgesia as compared with those in the control group ( CONCLUSIONS Escin can alleviate chemotherapy-induced peripheral neuropathic pain in rats possibly by upregulating the expressions of autophagy-related proteins in the spinal cord.
Animals ; Antineoplastic Agents/therapeutic use* ; Autophagy ; Escin/therapeutic use* ; Hyperalgesia/drug therapy* ; Mice ; Neuralgia/drug therapy* ; Rats ; Rats, Sprague-Dawley ; Spinal Cord