Neurology (64)

Treatment of postherpetic neuralgia: an update. (University of Rochester School of Medicine and Dentistry, Rochester, NY) Drugs 2000;59:1113–1126.
This article provided an update on recent developments in the treatment of postherpetic neuralgia (PHN). In clinical trials, the topical lidocaine patch, gabapentin, and controlled release oxycodone have been shown to provide superior pain relief in patients with PHN when compared with placebo. It has also been demonstrated that the tricyclic antidepressant nortriptyline provides equivalent analgesic benefit when compared with amitriptyline, but is better tolerated. Based on these results, nortriptyline can now be considered the preferred antidepressant for treatment of PHN. The topical lidocaine patch, gabapentin, and controlled release oxycodone all appear to be as effective as tricycline antidepressants in the treatment of patients with PHN, and the results of these recent studies suggest that each of these treatments should be considered early in the course of treatment. Additional controlled trials are needed to compare the efficacy and tolerability of these 4 treatments for patients with PHN.     

Cost-effectiveness of a lidocaine 5% medicated plaster relative to gabapentin for postherpetic neuralgia in the United Kingdom

BACKGROUND: Approximately 50% of elderly patients develop postherpetic neuralgia (PHN) after herpes zoster infection (shingles). A lidocaine 5% medicated plaster marketed in the United Kingdom in January 2007 has been shown to be an effective topical treatment for PHN with minimal risk of systemic adverse effects. OBJECTIVE: This paper assessed the cost-effectiveness of using a lidocaine plaster in place of gabapentin in English primary care practice to treat those PHN patients who had insufficient pain relief with standard analgesics and could not tolerate or had contraindications to tricyclic antidepressants (TCAs). The analysis took the perspective of the National Health Service (NHS). METHODS: The costs and benefits of gabapentin and the lidocaine plaster were calculated over a 6-month time horizon using a Markov model. The model structure allowed for differences in costs, utilities, and transition probabilities between the initial 30-day run-in period and maintenance therapy and also accounted for add-in medications and drugs received by patients who discontinued therapy. Most transition probabilities were based on non-head-to-head clinical trials identified through a systematic review. Data on resource utilization, discontinuation rates, and add-in or switch medications were obtained from a Delphi panel; cost data were from official price tariffs. Published utilities were adjusted for age and were supplemented and validated by the Delphi panel. RESULTS: Six months of therapy with the lidocaine plaster cost pound 549 per patient, compared with pound 718 for gabapentin, and generated 0.05 more quality-adjusted life-years (QALYs). The lidocaine plaster therefore dominated gabapentin (95% CI, dominant- pound 2163/QALY gained). Probabilistic sensitivity analysis showed that there was a 90.15% chance that the lidocaine plaster was both less costly and more effective than gabapentin and a 99.99% chance that it cost < pound 20,000/QALY relative to gabapentin. Extensive deterministic sensitivity analyses confirmed the robustness of the conclusions. CONCLUSION: This study found that the lidocaine 5% medicated plaster was a cost-effective alternative to gabapentin for PHN patients who were intolerant to TCAs and in whom analgesics were ineffective, from the perspective of the NHS.     

The use of gabapentin for the treatment of postherpetic neuralgia

BACKGROUND: Varicella-zoster virus causes chickenpox and can reemerge later in life to cause herpes zoster or shingles. One of the most common and disabling complications of herpes zoster is postherpetic neuralgia (PHN). OBJECTIVES: This article reviews the current primary literature about the efficacy and tolerability of gabapentin for the treatment of PHN. Gabapentin pharmacokinetics and drug interactions are also reviewed. METHODS: A literature search in the English language was conducted using OVID Web, which contained the following databases: MEDLINE (1966-present), EMBASE (1980-2002), Current Contents/Clinical Medicine (1999-2002), Cochrane Controlled Trials Register (1898-present), Cochrane Database of Systemic Reviews (fourth quarter, 2002), and International Pharmaceutical Abstracts (1970-2002). Search terms used were postherpetic neuralgia; zoster; gabapentin; neuropathic pain; pain; pharmacoeconomic; cost; controlled clinical trial; randomized, controlled trial; postherpetic neuralgia and gabapentin; gabapentin and pain; treatment and postherpetic neuralgia; gabapentin and age; gabapentin and gender; gabapentin and ethnicity; and gabapentin and pharmacokinetics. RESULTS: Gabapentin displays nonlinear absorption kinetics, is minimally protein bound (< 3%), has a high mean (SD) volume of distribution (50.4 [8.0] L), and is excreted via the kidneys as unchanged drug. Two randomized, placebo-controlled, parallel-group, multicenter clinical trials demonstrated the effectiveness of gabapentin at doses of up to 3600 mg/d to significantly reduce pain (P < 0.01 and P < 0.001), improve sleep (P < 0.01), and improve some parameters on the Short Form-McGill Pain Questionnaire (P < 0.05). Dizziness and somnolence were the most common side effects leading to withdrawal from the trials. The recommended dosage in adults is 300 mg at bedtime on day 1,300 mg BID on day 2, and 300 mg TID on day 3, titrating up as needed to 2400 to 3600 mg/d. To reduce adverse events in patients with renal impairment, the dose should be adjusted based on the patient's creatinine clearance. CONCLUSIONS: Gabapentin appears to be effective and well tolerated for the short-term treatment of PHN. However, future controlled studies are needed to determine whether the effectiveness of gabapentin for PHN is maintained for > 2 months, to establish the optimal dose of gabapentin for PHN, and to compare the efficacy of gabapentin with that of other pharmacologic agents used for the treatment of PHN.     

Treatment of postherpetic neuralgia: a review of therapeutic options

Postherpetic neuralgia (PHN) is a disabling consequence of the reactivation of the varicella zoster infection. The observation that patients with PHN experience various types of pain suggests that multiple pathophysiologic mechanisms are involved, which may include the peripheral and central nervous systems. A reasonable initial strategy would involve selecting from among multiple agents that have complementary mechanisms of action and that have been proven effective in controlled clinical trials, such as the lidocaine patch 5%, gabapentin, tricyclic antidepressants, and opioids. Based on initial assessment and ongoing reassessment, sequential trials should be undertaken until adequate pain relief is achieved. This may ultimately lead to therapy with more than one medication. Safety and tolerability are important considerations in choosing initial therapy, particularly in older patients. Physicians can either add another agent to the current regimen or switch to a new type of monotherapy if there is inadequate response to initial therapy. Alternative therapies, (i.e., ketamine, intrathecal corticosteroid injections) have not been adequately studied. Well-designed, multicenter, controlled clinical trials are needed to develop a treatment algorithm that provides an evidence-based, rational approach to treating PHN.     

Herpes zoster and postherpetic neuralgia: prevention and management

The recognizable appearance and the dermatomal distribution of herpes zoster lesions usually enable a clinical diagnosis to be made easily. Herpes zoster and postherpetic neuralgia occur mainly in older patients. The role of the varicella vaccine in preventing herpes zoster is uncertain, but is being studied. There is evidence to support using antiviral therapy and possibly low-dose tricyclic antidepressants to prevent postherpetic neuralgia. There is good evidence that treating herpes zoster with antiviral medication is beneficial, particularly in patients older than 50 years with severe outbreaks. The use of steroids has an unfavorable risk-benefit ratio. In patients who develop postherpetic neuralgia, there is good evidence to support treatment with gabapentin and tricyclic antidepressants. More evidence for treatment with capsaicin cream, lidocaine patch, and opioids is needed. Intrathecal methylprednisolone is an option for patients with persistent pain.     

Review of current guidelines on the care of postherpetic neuralgia

An unfortunate minority of patients with acute herpes zoster (AHZ) experience pain beyond the typical 4-week duration, and roughly 10% develop the distressing complication of postherpetic neuralgia (PHN), often defined as pain persisting for > 4 months after the onset of the rash. Elderly patients are at increased risk of PHN. The pathophysiology of PHN is complex, likely involving both peripheral and central processes. This complexity may create opportunities for pharmacologic interventions with multiple differing mechanisms of action. Consequently, complementary combinations of pharmacologic agents are frequently more effective than any monotherapy. Current US and international guidelines on the care of patients with PHN are reviewed and interpreted here to facilitate their effective incorporation into the practice of primary care physicians, acknowledging the contrasts that often exist between the clinical trial populations analyzed to craft so-called evidence-based medicine and the individual patients seen in daily practice, many of whom may not have been candidates for those clinical trials. First-line treatments for PHN include tricyclic antidepressants, gabapentin and pregabalin, and the topical lidocaine 5% patch. Opioids, tramadol, capsaicin cream, and the capsaicin 8% patch are recommended as either second- or third-line therapies in different guidelines. Therapies that have demonstrated effectiveness for other types of neuropathic pain are discussed, such as serotonin-norepinephrine reuptake inhibitors, the anticonvulsants carbamazepine and valproic acid, and botulinum toxin. Invasive procedures such as sympathetic blockade, intrathecal steroids, and implantable spinal cord stimulators have been studied for relief of PHN, mainly in patients refractory to noninvasive pharmacologic interventions. The main guidelines considered here are those issued by the American Academy of Neurology for the treatment of postherpetic neuralgia (2004) and general guidelines for the treatment of neuropathic pain issued by the Special Interest Group on Neuropathic Pain of the International Association for the Study of Pain (2007) and the European Federation of Neurological Societies (2010).     

Herpes zoster and postherpetic neuralgia: prevention and management

Herpes zoster (shingles) is diagnosed clinically by recognition of the distinctive, painful vesicular rash appearing in a unilateral, dermatomal distribution. An estimated 1 million cases occur in the United States each year, and increasing age is the primary risk factor. Laboratory testing, including polymerase chain reaction, can confirm atypical cases. Treatment with acyclovir, famciclovir, or valacyclovir decreases the duration of the rash. Adjunct medications, including opioid analgesics, tricyclic antidepressants, or corticosteroids, may relieve the pain associated with acute herpes zoster. There is conflicting evidence that antiviral therapy during the acute phase prevents postherpetic neuralgia. Postherpetic neuralgia in the cutaneous nerve distribution may last from 30 days to more than six months after the lesions have healed. Evidence supports treating postherpetic neuralgia with tricyclic antidepressants, gabapentin, pregabalin, long-acting opioids, or tramadol; moderate evidence supports the use of capsaicin cream or a lidocaine patch as a second-line agent. Immunization to prevent herpes zoster and postherpetic neuralgia is recommended for most adults 60 years and older.     

Double-blind, placebo-controlled trial of lamotrigine in combination with other medications for neuropathic pain

This randomized, double-blind, placebo-controlled study was undertaken to evaluate the efficacy and tolerability of lamotrigine added to gabapentin, a tricyclic antidepressant, or a nonopioid analgesic in patients whose neuropathic pain was inadequately controlled with these medications. Patients with neuropathic pain from diabetic peripheral neuropathy, postherpetic neuralgia, traumatic/surgical nerve injury, incomplete spinal cord injury, trigeminal neuralgia, multiple sclerosis, or HIV-associated peripheral neuropathy, who had a mean weekly pain score > or =4 on an 11-point numerical rating scale, were randomized to receive a flexible dose of lamotrigine 200, 300, or 400mg daily (n=111) or placebo (n=109) for up to 14 weeks (including eight weeks of dose escalation) in addition to their prestudy regimen of gabapentin, a tricyclic antidepressant, or a nonopioid analgesic. No statistically significant difference in the mean change in pain-intensity score from baseline to Week 14 (primary endpoint) was detected between lamotrigine and placebo (P=0.67). Differences between lamotrigine and placebo were not statistically significant for secondary efficacy assessments, including mean changes from baseline in the Short-Form McGill Pain Questionnaire, the Neuropathic Pain Scale, rescue medication use, and the percentages of patients rated as much improved or very much improved at the end of treatment on the Clinician Global Impression of Change scale and the Patient Global Impression of Change scale. Lamotrigine was generally well tolerated. Lamotrigine (up to 400 mg/day) added to gabapentin, a tricyclic antidepressant, or a nonopioid analgesic did not demonstrate efficacy as an adjunctive treatment of neuropathic pain but was generally safe and well tolerated.     

Herpes zoster in older adults. (Duke University Medical Center, Durham, NC) Clinical Infectious Diseases. 2001;32:1481–1486.

Herpes zoster (HZ) strikes millions of older adults annually worldwide and disables a substantial number of them via postherpetic neuralgia (PHN). Key aged‐related clinical, epidemiological, and treatment features of zoster and PHN are reviewed in this article. HZ is caused by renewed replication and spread of the varicella‐zoster virus (VZV) in sensory ganglia and afferent peripheral nerves in the setting of age‐related, disease‐related, and drug‐related decline in cellular immunity to VZV. VZV‐induced neuronal destruction and inflammation causes the principal problems of pain, interference with activities in daily living, and reduced quality of life in elderly patients. Recently, attempts to reduce or eliminate HZ pain have been bolstered by the findings of clinical trials that antiviral agents and corticosteroids are effective treatment for HZ and that tricyclic antidepressants, topical lidocaine, gabapentin, and opiates are effective treatment for PHN. Although these advances have helped, PHN remains a difficult condition to prevent and treat in many elderly patients. Comment by Miles Day, M.D. This article reviews the epidemiology clinical features diagnosis and treatment of acute herpes zoster. It also describes the treatment of postherpetic neuralgia. While this is a good review for the primary care physician, the discussion for the treatment for both acute herpes zoster and postherpetic neuralgia do not mention invasive therapy. It is well documented in pain literature that sympathetic blocks with local anesthetic and steroid as well as subcutaneous infiltration of active zoster lesions not only facilitate the healing of acute herpes zoster but also prevents or helps decrease the incidence of postherpetic neuralgia. All patients who present to the primary care physician with acute herpes zoster should have an immediate referral to a pain management physician for invasive therapy. The treatment of postherpetic neuralgia is a challenging experience both for the patient and the physician. While the treatments that have been discussed in this article are important, other treatments are also available. Regional nerve blocks including intercostal nerve blocks, root sleeve injections, and sympathetic blocks have been used in the past to treat postherpetic neuralgia. If these blocks are helpful, one can proceed with doing crynourlysis of the affected nerves or also radio‐frequency lesioning. Spinal cord stimulation has also been used for those patients who are refractory to noninvasive and invasive therapy. While intrathecal methylprednisolone was shown to be effective in the study quoted in this article one must be cautious not to do multiple intrathecal steroid injections in these patients. Multilple intrathecal steroid injections can lead to archnoiditis secondary to the accumulation of the steroid on the nerve roots and in turn causing worsening pain.     

Factors influencing the features of postherpetic neuralgia and outcome when treated with tricyclics.

This paper retrospectively reviews features of postherpetic neuralgia (PHN) in up to 279 personal patients in relation to treatment outcome when treated with tricyclic antidepressants (TCAs). Factors affecting characteristics of PHN: (i) Patients with allodynia (89%) and/or burning pain (56%) have a much higher visual analogue pain intensity score than those without; (ii) Acyclovir (ACV) given for acute shingles (HZ) does not reduce the incidence of subsequent PHN, but reduces the pain intensity in PHN patients with allodynia; (iii) ACV given for acute HZ reduces the incidence of burning pain in subsequent PHN, but not of allodynia; (iv) ACV given for acute HZ reduces the incidence of clinically detectable sensory deficit in subsequent PHN. Factors affecting outcome of TCA-treated PHN: (i) The point in time at which TCA treatment is commenced is by far the most critical factor: started between 3 and 12 months after acute HZ onset, more than two-thirds obtain pain relief (NNT=1.8); between 13 and 24 months, two-fifths (41%) (NNT=3.6); and more than two years, one-third (NNT=8.3). Background and paroxysmal pain disappear earlier and are more susceptible of relief than allodynia. (ii) Twice as many (86%) of PHN patients without allodynia obtain pain relief with TCA treatment than those with (42%); (iii) the use of ACV for acute HZ more than halves the time-to-relief of PHN patients by TCAs; (iv) PHN patients with burning pain are significantly less likely to obtain pain relief with TCAs than those without (p<0.0001).     

Is treatment of postherpetic neuralgia in the community consistent with evidence-based recommendations?

Few studies have examined the extent to which treatment of patients with neuropathic pain in the community is consistent with evidence-based treatment recommendations. U.S. health care claims were used to identify patients who received a diagnosis of postherpetic neuralgia (PHN). The initial pharmacologic treatments and changes to these treatment regimens were categorized according to the International Association for the Study of Pain Neuropathic Pain Special Interest Group recommendations for first-, second-, and third-line treatment of neuropathic pain. The results indicated that the treatment of PHN was only partially consistent with these treatment recommendations. Of the patients diagnosed with PHN who were not already on a specified treatment, 70% began treatment with either a first-, second-, or third-line treatment or a not-recommended treatment, and 30% did not begin treatment with any of these medications. Only one-quarter of patients began treatment with a first-line medication, the same percentage that began treatment with either a third-line medication or a not-recommended treatment. There was a wide range of initial treatment durations, but the means and medians suggest that patients and clinicians often decide to change the initial treatment within 2 months, either by discontinuing it, replacing it with a new medication, or adding a new medication. Although there were generally shorter treatment durations with opioid analgesics and tramadol, these medications were more frequently used in beginning treatment than the other treatments. The results suggest that a considerable number of patients with PHN in the community are not receiving evidence-based treatment.     

Desipramine relieves postherpetic neuralgia

Desipramine has the least anticholinergic and sedative effects of the first generation tricyclic antidepressant agents, but its pain-relieving potential has received little study. Other antidepressant agents--notably amitriptyline--are known to ameliorate postherpetic neuralgia, but those agents are often toxic. In a randomized double-blind crossover design, we gave 26 postherpetic neuralgia patients 6 weeks of treatment with desipramine (mean dose, 167 mg/day) and placebo. Nineteen patients completed both treatments; 12 reported at least moderate relief with desipramine and two reported relief with placebo. Pain relief with desipramine was statistically significant from weeks 3 to 6. Psychiatric interview at entry into the study produced a diagnosis of depression for 4 patients; pain relief was similar in depressed and nondepressed patients and was statistically significant in the nondepressed group alone. We conclude that desipramine administration relieves postherpetic neuralgia and that pain relief is not mediated by mood elevation. Blockade of norepinephrine reuptake, an action shared by desipramine, amitriptyline, and other antidepressant agents that have relieved neuropathic pain, may be involved in relief of postherpetic neuralgia.     

Post-herpetic neuralgia: the relation of pain complaint, sensory disturbance, and skin temperature

Twelve otherwise healthy patients with longstanding postherpetic neuralgia (PHN) were prospectively studied using clinical examination, infrared thermography and response to local anesthetic skin infiltration. All had at least 2 of 3 possible components to their PHN pain: continuous, neuralgic, or allodynic. In patients with allodynia, maximal reported pain and the location of maximal allodynia on sensory examination were largely overlapping and were often warm thermographically. Areas of dense sensory loss and skin scarring without allodynia were usually cool thermographically. Local anesthetic skin infiltration produced substantial pain relief in all 9 patients (essentially complete relief in 7) with allodynia: the 3 patients with predominantly continuous pain were not relieved. In 7 of 8 skin infiltration responders, the same dose of lidocaine i.m. in the deltoid muscle also produced significant, though less complete pain relief. These results suggest that PHN patients can be divided into at least 2 clinical groups: those with predominantly continuous pain localized to a region of significant sensory loss and those in whom allodynia is the most prominent sensory disturbance. The latter group has pain localized to areas with relatively preserved sensation. The differences in clinical features and response to lidocaine suggest that there are at least 2 different mechanisms contributing to the pain of PHN.     

Cost-effectiveness of pregabalin for the management of neuropathic pain associated with diabetic peripheral neuropathy and postherpetic neuralgia: a Canadian perspective

BACKGROUND: Neuropathic pain (NeP) is a chronic condition that occurs frequently with diabetes and herpes zoster infection. In addition to potentially lasting many years, the relationship between chronic pain, anxiety/depression, and sleep, also referred to as the triad of pain, causes functional impairment in many areas of life. OBJECTIVE: The aim of this study was to examine the 12-week cost-effectiveness of 2 treatments of NeP, pregabalin versus gabapentin, in managing diabetic peripheral neuropathy (DPN) and postherpetic neuralgia (PHN) in a Canadian setting. METHODS: A stochastic simulation model evaluating NeP treatment was adapted to the Canadian setting. Using data from clinical trials of pregabalin (150-600 mg/d) and gabapentin (900-3600 mg/d), the model simulated 12-week treatment outcomes for patients with DPN or PHN. Resource utilization was identified through an Internet-based survey among 80 Canadian physicians. Utility values (as measured using the EuroQol EQ-5D) were obtained from 126 NeP patients participating in a cross-sectional study conducted at Canadian primary care sites. The economic analysis was expressed as incremental cost per quality-adjusted life year (QALY) gained and as incremental cost per day with no or mild pain. Model sensitivity to changes in key parameters was assessed. RESULTS: Following 12-week treatment, compared with gabapentin, pregabalin was projected to result in 6 and 9 additional days with no or mild pain for patients with DPN and PHN, respectively. Pregabalin therapy was estimated to provide an additional 0.0047 QALY and 0.0086 QALY over gabapentin administration, for DPN and PHN, respectively. Mean (SE) direct costs per DPN patient were estimated as 837.53 Can dollars (37.31 dollars) (2004 dollars) with gabapentin and 818.49 dollars (36.50 dollars) with pregabalin, and per PHN patient as 720.61 dollars (33.70 dollars) with gabapentin and 667.07 dollars (25.33 dollars) with pregabalin. Model findings were sensitive to variation in the dose and corresponding cost of the comparator, but not in other parameters. CONCLUSION: Based on the results of this analysis, in the treatment of NeP associated with DPN or PHN, pregabalin was a dominant or cost-effective treatment strategy compared with gabapentin.     

阿片类药物在慢性非癌性疼痛中的应用

目的:回顾性分析卡马西平和加巴喷丁治疗原发性三叉神经痛、带状疱疹以及带状疱疹后遗神经痛的疗效、安全性和不良反应。方法:102位患者进入本研究,比较卡马西平或加巴喷丁治疗前后患者疼痛强度的改变和对睡眠影响的改善;依据药物分类,比较两种药物的副作用和不良反应。结果:卡马西平治疗原发性三叉神经痛起效较加巴喷丁快,二者长期疗效相当;加巴喷丁治疗带状疱疹和带状疱疹后神经痛的疗效优于卡马西平;疗效随治疗时间的延长而增加。卡马西平的副作用和不良反应事件发生率较加巴喷丁高。结论:抗癫痫药物卡马西平和加巴喷丁是治疗神经病理性疼痛的有效药物,可以改善患者的睡眠,但副作用和不良反应发生率高。     

加巴喷丁治疗带状疱疹后遗神经痛的临床研究

目的探讨加巴喷丁治疗带状疱疹后遗神经痛的临床效果与安全性。方法带状疱疹后遗神经痛患者32例,随机分为2组,每组16例,均给常规药物治疗。在此基础上加巴喷丁组给予加巴喷丁,剂量自300-900 mg,最大增至1 200 mg/d,分3次口服;卡马西平组服用卡马西平100-300 mg/次,3次/d,剂量1 200 mg/d。2组疗程均为4周,分别于治疗前及治疗后1、2、4周采用视觉模拟评分（VAS）进行疼痛评估,评定治疗效果,同时观察患者的不良反应。结果2组患者VAS评分及疗效比较差异无统计学意义（P〉0.05）,但加巴喷丁组不良反应作用较少且轻微。结论带状疱疹后遗神经痛应用加巴喷丁治疗安全有效。     

Use of gabapentin for postherpetic neuralgia: results of two randomized, placebo-controlled studies

BACKGROUND: Postherpetic neuralgia (PHN), which affects up to 70% of elderly persons with herpes zoster, can have debilitating effects, including physical and social disability and significant psychological distress. A variety of agents have been used, either singly or in combination, to control PHN, including topical and oral analgesics, antidepressants, and antiepileptic drugs (AEDs). However, PHN often proves refractory to these therapies. OBJECTIVE: This article reviews available data on the use of the newer AED gabapentin for the control of PHN. METHODS: A MEDLINE search was undertaken to identify all randomized, placebo-controlled trials on the use of gabapentin in PHN. The search terms were gabapentin and postherpetic neuralgia. RESULTS: The literature search identified 2 published studies of the efficacy of gabapentin in a total of 563 patients with PHN that had persisted for at least 3 months after the healing of herpes zoster rash. The studies employed multiple outcome measures, including visual analog and Likert scales for pain intensity, and quality-of-life and functional measures that included the Medical Outcomes Study 36-item Short Form Health Survey (SF-36) and the Profile of Mood States. At maximum target dosages of 1800 to 3600 mg/d, gabapentin produced significant reductions in mean daily pain scores compared with placebo on both visual analog(P < 0.001) and Likert scales (P < 0.01). Improvements were also seen on the SF-36 subscales for physical functioning, bodily pain, vitality, and mental health(P < 0.01). CONCLUSION: Gabapentin may provide benefits in terms of alleviation of pain and overall quality of life in patients with chronic PHN.     

普瑞巴林或加巴喷丁药物联合神经阻滞治疗带状疱疹后神经痛的疗效比较

【目的】对比分析普瑞巴林联合神经阻滞和加巴喷丁联合神经阻滞治疗带状疱疹（HZ）后神经痛（PHN）的疗效和安全性。【方法】收集PHN患者100例,按照治疗方法分为两组,每组50例,A组采用口服普瑞巴林联合神经阻滞治疗,B组采用加巴喷丁联合神经阻滞治疗,共治疗3周。用视觉模拟评分（visual an-alogue scale,VAS）和24 h睡眠时间来评价治疗效果,同时观察两组并发症及药物不良反应。【结果】在3周住院期间,两组患者治疗后各时点与治疗前相比疼痛评分随时间下降,睡眠时间均增加（P ＜0．05）;A组的VAS评分下降大于B组,24 h睡眠时间增加大于B组（P＜0．05）;两组未出现并发症及严重的药物副作用。【结论】普瑞巴林联合神经阻滞及加巴喷丁联合神经阻滞治疗 PHN,均可迅速缓解疼痛,改善睡眠质量,但前者疗效优于后者。     

Post-herpetic Neuralgia: a Review

Post-herpetic neuralgia (PHN) is a chronic neuropathic pain condition that persists 3 months or more following an outbreak of shingles. Shingles, also known as acute herpes zoster, is associated with the reactivation of the dormant varicella zoster virus in an individual who has experienced chicken pox. PHN is associated with persistent and often refractory neuropathic pain. Patients may experience multiple types of pain including a constant deep, aching, or burning pain; a paroxysmal, lancinating pain; hyperalgesia (painful stimuli are more painful than expected); and allodynia (pain associated with typically non-painful stimuli). The pharmacological treatment of PHN may include a variety of medications including alpha-2 delta ligands (gabapentin and pregabalin), other anticonvulsants (carbamazepine), tricyclic antidepressants (amitriptyline, nortriptyline, doxepin), topical analgesics (5 % lidocaine patch, capsaicin) tramadol, or other opioids. The considerable side effect profiles of the commonly used oral medications often limit their practical use, and a combination of both topical and systemic agents may be required for optimal outcomes. Physicians and other treatment providers must tailor treatment based on the response of individual patients.     

Sympathetic nerve blocks in mandibular herpes zoster and postherpetic neuralgia

Sympathetic blocks have been indicated for the diagnosis and treatment of painful neuropathic conditions, such as herpes zoster (HZ) and postherpetic neuralgia (PHN). The purpose of this article is to report a case of mandibular HZ and PHN in an HIV-positive patient, and discuss the efficacy of sympathetic nerve blocks for pain relief and prevention of PHN.