The topical 5% lidocaine medicated plaster in localized neuropathic pain: a reappraisal of the clinical evidence

Lidocaine patch as noninvasive alternative treatment option in children with anterior cutaneous nerve entrapment syndrome: A retrospective case series

BACKGROUND

Chronic abdominal pain in children is occasionally caused by anterior cutaneous nerve entrapment syndrome (ACNES). Diagnosing and treating this typical peripheral abdominal wall neuropathy is challenging. Management usually starts with minimally invasive tender point injections. Nevertheless, these injections can be burdensome and might even be refused by children or their parents. However, a surgical neurectomy is far more invasive. Treatment with a Lidocaine 5% medicated patch is successfully used in a variety of peripheral neuropathies.

AIMS

This single center retrospective case series aimed to evaluate the effectiveness and tolerability of lidocaine patches in children with ACNES.

METHODS

Children aged under 18 diagnosed with ACNES who were treated with a 10 day lidocaine patch treatment between December 2021 and December 2022 were studied. Patient record files were used to collect treatment outcomes including pain reduction based on NRS and complications.

RESULTS

Twelve of sixteen children (mean age 13 years; F:M ratio 3:1) diagnosed with ACNES started the lidocaine patch treatment. Two patients achieved a pain free status and remained pain free during a 4 and 7 months follow-up. A third child reported a lasting pain reduction, but discontinued treatment due to a temporary local skin rash. Five additional patients reported pain reduction only during application of the patch. The remaining four children experienced no pain relief. No adverse effects were reported.

CONCLUSION

Lidocaine patches provides pain relief in a substantial portion of children with ACNES.

Trigeminal Postherpetic Neuralgia: From Pathophysiology to Treatment

PURPOSE OF REVIEW

Trigeminal postherpetic neuralgia (TG-PHN) is a neuropathic pain condition complicating herpes zoster (HZ) attributed to the trigeminal nerve. It poses significant challenges due to its persistent and debilitating nature. This review explores the clinical characteristics of TG-PHN, analyzes its pathophysiological underpinnings, and addresses existent and potential therapies.

RECENT FINDINGS

TG-PHN is one of the most common and complex PHN locations. It has distinguishing clinical and pathophysiological characteristics, starting with viral triggered injuries to the trigeminal ganglion (TG) and peripheral tissue and involving the ascending and descending brain modulation pathways. Current therapies include vaccines, oral and topical medications, and interventional approaches, like nerve blocks and neurostimulation. This review covers TG-PHN's clinical and physiological components, treatment options, and potential future targets for improved management. By exploring the complexities of this condition, we aim to contribute to developing more effective and targeted therapies for patients suffering from trigeminal PHN.

Therapeutic Strategies for Postherpetic Neuralgia: Mechanisms, Treatments, and Perspectives

PURPOSE OF REVIEW

Postherpetic neuralgia is an annoying pain that mainly affects older people. In order to give patients more options, this review summarizes the pharmacological and interventional treatments for postherpetic neuralgia and updates the research on the efficacy, thereby providing doctors with more treatment options. The adverse effects and effective doses of its various treatments are also presented so that the therapy can be prescribed according to their concrete physical conditions. In a word, this review is dedicated to providing a comprehensive overview of the treatment options for postherpetic neuralgia and offering patients more choices.

RECENT FINDINGS

Combinational therapy is more excellent than monotherapy. The local anesthesia and gabapentin comprised outstanding compatibility. In addition, two therapeutic tools for PHN patients, especially for the intractable ones, electroacupuncture (EA), and osteopathic manipulative treatment (OMT), show their efficacy and become potential options to alleviate pain. In terms of treatment, guidelines recommend patients use tricyclic antidepressants (TCAs), gabapentin, pregabalin, and 5% lidocaine patches as the first-line medications, and gabapentin is investigated most, especially the gabapentin enacarbil (GEn). And drug efficacy can be limited by adverse effects and tolerated doses. Interventional treatments, with their invasiveness and operational difficulty, are usually considered for intractable patients. Combinational therapies may be used when a single therapy cannot achieve the desired effect. Therapies such as OMT and EA have also been proposed to palliate pain in some cases, and future directions of treatment may be investigated in Chinese medicine and acupuncture.

Randomized, Placebo-Controlled, Multicenter Clinical Study on the Efficacy and Safety of Lidocaine Patches in Chinese Patients with Postherpetic Neuralgia

INTRODUCTION

To evaluate the efficacy and safety of lidocaine patches in Chinese patients with postherpetic neuralgia (PHN).

METHODS

Patients were randomized to receive lidocaine patches or placebo every day for 4 weeks. Efficacy endpoints included the decrease of analogue scale score (VAS) value at week 4, 2 and 1 and the percentage of patients that achieved a 30% decrease of VAS value. Safety analyses were conducted as well.

RESULTS

Two hundred forty Chinese patients were randomized. At week 1, lidocaine patch-treated patients had a higher clinical response versus placebo, and at week 4, the mean (SD) decreases of VAS value compared to the baseline were 14.01 (14.35) in the treatment group and 9.36 (12.03) in the placebo group (p = 0.0088). Overall, the safety profile in the treatment group was consistent with that observed in the placebo group [adverse event (AE) incidence rate: 33.33% versus 37.29%, p = 0.5857].

CONCLUSIONS

Lidocaine patches resulted in improved clinical response versus placebo in the treatment of PHN patients and were well tolerated.

Dexmedetomidine Co-Administered with Lidocaine Decreases Nociceptive Responses and Trigeminal Fos Expression without Motor Dysfunction and Hypotension in a Murine Orofacial Formalin Model

Administration of dexmedetomidine significantly induces sedation and anti-nociception in several nociceptive models, but clinical trials are restricted due to adverse side effects, including lethargy, hypotension, and bradycardia. Herein, we investigated whether intraperitoneal inoculation of dexmedetomidine reduced the orofacial nociceptive response and affected motor coordination and blood pressure and examined whether a lower dose of dexmedetomidine in combination with 0.5% lidocaine produced an antinociceptive effect without any adverse side events in a murine model. To perform the experiment, 5% formalin (10 µL) was subcutaneously inoculated into the right upper lip, and the rubbing responses were counted for 45 min. Different doses of dexmedetomidine combined with 0.5% lidocaine were administered 10 and 30 min before formalin injection, respectively. Dexmedetomidine (10 μg/kg) significantly reduced orofacial nociceptive responses during the second phase of the formalin test and decreased the expression of Fos in trigeminal nucleus caudalis (TNC). Besides, a high dose of dexmedetomidine (30 μg/kg) induced lessening physical ability and significantly reduced systolic pressure and heart rate. When 0.5% lidocaine was injected subcutaneously, nociceptive responses were reduced only in the first phase. Interestingly, although a low dose of dexmedetomidine (3 μg/kg) alone did not show an antinociceptive effect, its co-administration with lidocaine significantly reduced the nociceptive response in both phases and decreased TNC Fos expression without motor dysfunction and hypotension. This finding suggests that the combination of a low-dose of systemic dexmedetomidine with lidocaine may be a safe medicinal approach for acute inflammatory pain management in the orofacial region, particularly mucogingival pain.

Localized peripheral neuropathic pain: topical treatment with lidocaine 700 mg medicated plaster in routine clinical practice

Aim: To provide real-world evidence for the effectiveness and tolerability of lidocaine 700 mg medicated plaster (LMP) in localized peripheral neuropathic pain (l-PNP) treatment compared with first-line oral medications (OM). Patients & methods: This was a noninterventional, retrospective 6-month cohort study in patients refractory to at least one recommended OM, using anonymized medical care data from the German Pain eRegistry. Treatment groups were matched by propensity scoring, considering seven predefined confounding factors. The primary effectiveness end point was the absolute change in average pain intensity index from baseline at weeks 4, 12 and 24 of treatment and over the treatment period. Results: A total of 3081 datasets were retained per treatment group. LMP provided superior pain reductions and significantly greater improvements in pain-related impairments of daily living and quality of life with significantly better tolerability (p < 0.001 for all parameters) than OM. Conclusion: These real-world data confirm the effectiveness and good tolerability of LMP for l-PNP treatment under routine medical care.

Application of 5% Lidocaine Adhesive Patch in Painful Surgical Scars: Clinical Trial

Objective  The present paper aims to evaluate the use of a 5% lidocaine patch to treat neuropathic pain after orthopedic procedures in comparison with therapeutic massage over surgical incisions. Methods  This is a prospective, randomized clinical trial with 37 patients who underwent orthopedic surgery from January 2015 to February 2017. The study included subjects aged 13 to 70 years old who underwent foot and ankle orthopedic surgery and presented neuropathic pain or hypersensitivity at the surgical incision site for at least 90 days after the procedure. All patients were assessed for pain (using the visual analog scale [VAS]) and quality of life (with the SF-36 questionnaire) at the beginning of the treatment and after 30, 60, and 90 days. Results  Although the treatment improved pain in both groups, subjects using the lidocaine patch presented greater pain reduction over time. There were no statistically significant differences in the SF-36 questionnaire, with no significant evidence regarding functional capacity, physical aspects, vitality, emotional aspects, social aspects, general health condition, and mental health. The great advantage of the patch was the degree of personal satisfaction of the patients, with statistical relevance, probably due to the easy application and psychological effect of a drug therapy. Conclusion  Lidocaine patches and massages are effective treatment methods for reducing scar tissue pain, with similar outcomes. The patches improved the degree of patient satisfaction. Level of Evidence 1. Prospective randomized clinical trial.

Topical Lidocaine for Chronic Pain Treatment

Topical lidocaine is widely used in current practice for a variety of pain conditions. This literature review shows that its limited absorption and relative lack of systemic adverse events are an attractive analgesic option for a number of vulnerable patients. Topical lidocaine has been approved by health authorities for the treatment of post-herpetic neuralgia in a number of countries, and studies present some degree of evidence of its efficacy and safety in postsurgical pain, diabetic peripheral neuropathy, carpal tunnel syndrome, chronic lower back pain and osteoarthritis. Topical lidocaine may be a great alternative alone or in addition to systemic drugs and non-pharmacological approaches for an optimized pain management and in multimodal analgesia.

Lidocaine 700 mg medicated plaster for postherpetic neuralgia: real-world data from the German Pain e-Registry

Aim: To provide real-world evidence for the effectiveness and tolerability of lidocaine 700 mg medicated plaster (LMP) compared with oral systemic first-line medications (OSM) in postherpetic neuralgia treatment. Patients & methods: Retrospective cohort study in patients refractory to at least one recommended OSM (single drug or a combination of drugs) using anonymized routine medical care data from the German Pain e-Registry. A matched pair approach using propensity score matching was employed. Results: A total of 1711 data sets of postherpetic neuralgia patients were identified per treatment group. The majority (>60%) had experienced pain for more than a year and reported a high burden of pain and reduced quality of life. Six months of LMP treatment provided significantly greater pain reductions, improvements in pain-related impairments and quality of life than OSM treatment (p < 0.001 for all parameters). Drug-related adverse events and treatment discontinuation due to drug-related adverse events also occurred less frequently under LMP treatment (p < 0.001). Conclusion: These real-world data confirm the effectiveness and good tolerability of LMP under routine medical care. The treatment was significantly more effective when compared with first-line oral systemic medications.

Expert consensus of the Chinese Association for the Study of Pain on pain treatment with the transdermal patch

Chronic pain lasting more than 3 mo, or even several years can lead to disability. Treating chronic pain safely and effectively is a critical challenge faced by clinicians. Because administration of analgesics through oral, intravenous or intramuscular routes is not satisfactory, research toward percutaneous delivery has gained interest. The transdermal patch is one such percutaneous delivery system that can deliver drugs through the skin and capillaries at a certain rate to achieve a systemic or local therapeutic effect in the affected area. It has many advantages including ease of administration and hepatic first pass metabolism avoidance as well as controlling drug delivery, which reduces the dose frequency and side effects. If not required, then the patch can be removed from the skin immediately. The scopolamine patch was the first transdermal patch to be approved for the treatment of motion sickness by the Food and Drug Administration in 1979. From then on, the transdermal patch has been widely used to treat many diseases. To date, no guidelines or consensus are available on the use of analgesic drugs through transdermal delivery. The pain branch of the Chinese Medical Association, after meeting and discussing with experts and based on clinical evidence, developed a consensus for promoting and regulating standard use of transdermal patches containing analgesic drugs.

The efficacy and safety profile of capsaicin 8% patch versus 5% Lidocaine patch in patients with diabetic peripheral neuropathic pain: a randomized, placebo-controlled study of south Asian male patients

Aims

Diabetic peripheral neuropathy affects up to 60% of individuals and often leads to foot ulceration and eventual amputation. When oral therapy has failed to achieve pain relief, the first line local treatment is the 5% lidocaine-medicated plaster which provides local relief. Capsaicin 8% patch is considered a promising topical treatment for diabetic peripheral neuropathy. The present study investigated the efficacy, safety and tolerability of capsaicin 8% patch vs 5% lidocaine patch treatments over 24 weeks in South Asian male diabetic patients with established peripheral diabetic neuropathy.

Methods

Analgesic effectiveness was assessed by observing any change in the Numeric Pain Rating Scale (NPRS) score, Brief Pain Inventory (BPI) for painful diabetic peripheral neuropathy (BPI-DPN question 4) and Patient Global Impression of Change (PGIC). All patients received 4% lidocaine gel/cream for 60 min prior to patch application. The trial was probably underpowered, taking into account the smaller than expected number of participants from the calculated 350 sample size required for the whole study. Two hundred ninety-one individuals were divided into three groups based on treatment regimen; Group LL (Lidocaine + Lidocaine), Group LP (Lidocaine + Placebo), Group LC (Lidocaine + Capsaicin). The treatment procedure was conducted once initially and then repeated once at 12 weeks. The patients were followed up on alternate weeks till 24 weeks after the initial treatment.

Results

Group LC experienced a more significant reduction in the average pain intensity (p < 0.05) during the last twenty-four hours. Group LC showed more significant reduction of pain compared to control (p < 0.01), a baseline score of 5.4 ± 1.2 dropped to 3.2 ± 1.5 by week 24 of treatment. The change in mean daily pain intensity was - 2.2 ± 1.5 [95% CI: -2.45, -1.5]. Group LL and LC experienced a significant overall improvement (slightly, much or very much) in the health status during the study. After the second week of the treatment, patient satisfaction scores were 2.1 ± 1.1 in Group LL which increased to 3.2 ± 1.2 by week 24 of treatment. The capsaicin 8% patch appears to be reasonably well tolerated since there were no discontinuations because of serious drug-related treatment emergent adverse event (TEAEs).

Conclusions

The aim of the present study was to assess the efficacy, safety and tolerability of the 8% capsaicin patch in patients with established painful diabetic neuropathy. There was a sustained treatment response to the initial and repeat treatment of the capsaicin 8% patch over the 24 weeks. The study population was very specific so further studies are required to investigate the generalizability of the results for patients experiencing painful diabetic neuropathy. The patch could be considered as an effective long-term treatment option in individuals with painful diabetic neuropathy, particularly those experiencing inadequate pain relief or side effects from systemic therapies.

Effect of an Online Reimbursement Application System on Prescribing of Lidocaine 5% Medicated Plaster in the Republic of Ireland

BACKGROUND

The lidocaine 5% medicated plaster, Versatis^®, has one therapeutic indication listed on the Summary of Product Characteristics-symptomatic relief of post-herpetic neuralgia (PHN) in adults. Increased expenditure on Versatis^® suggests that there is considerable off-label use. To support the appropriate use of Versatis^®, the Health Service Executive's Primary Care Reimbursement Service (PCRS) introduced a reimbursement application system for Versatis^® from 1 September 2017.

OBJECTIVE

The aim of this study was to investigate the effect of introducing a reimbursement application system on Versatis^® prescribing under the General Medical Services (GMS) scheme.

METHODS

This study was carried out using prescription dispensing data from the PCRS pharmacy claims database. We carried out segmented linear regression to assess changes in the Versatis^® prescribing rate per 1000 GMS eligible population, before and after the introduction of the online reimbursement application system.

RESULTS

The results of the segmented regression analysis show that there was a statistically significant level (- 4.91, p < 0.001) and trend change (- 0.69, p < 0.001) in the rate of Versatis^® prescribing post-introduction of the reimbursement application system. In the year prior to the introduction of the system, 2016, the annual GMS expenditure on Versatis^® lidocaine 5% patches was over €27 million, whereas the GMS expenditure in 2018 was reduced to just over €2 million.

CONCLUSION

In our study, a substantial decrease in the dispensing of Versatis^® was seen after the implementation of a reimbursement application system. Prescribing of Versatis^® should be restricted to patients with a diagnosis of PHN not only to reduce costs, but to ensure evidence-based use of this medication.

Postherpetic Neuralgia: Current Evidence on the Topical Film-Forming Spray with Bupivacaine Hydrochloride and a Review of Available Treatment Strategies

PURPOSE OF REVIEW

This is a comprehensive review of the literature about the use of bupivacaine hydrochloride for the treatment of post-herpetic neuralgia (PHN). It briefly reviews the background, biology, diagnosis and conventional treatment for PHN, and then introduces and compares the recent evidence for the use of topical bupivacaine.

RECENT FINDINGS

PHN is defined by pain lasting 90 days or more after the initial presentation of herpes zoster ("Shingles", HZ) rash and is the most common complication of this disease. A product of re-activation of the Varicella-Zoster virus (VZV), HZ is diagnosed more than 1 million times annually in the United States. Approximately 20% of patients with HZ will experience PHN and will continue to suffer intermittent neuropathic symptoms, including itching and pain, that is sharp, stabbing, throbbing or burning, with the pain localized to the site of their original rash. This long-lasting pain compares with the severity of long-standing rheumatics and osteo-arthritis and is accompanied by severe allodynia causing significant suffering, and a financial burden that is manifested in both healthcare costs and loss of quality-adjusted life years. Prevention of PHN may be achieved with the Zoster vaccine, although there is still a large segment of unvaccinated population. Moreover, the Zoster vaccine is not always effective for prevention. Current treatment includes medical (systemic tricyclic antidepressants, anticonvulsants and opioids, topical lidocaine and capsaicin) and interventional (subcutaneous Botox injections, nerve blocks and nerve stimulation) therapies. These therapies are not always effective, and each carries their own profile of side effects and risks. Moreover, up to 50% of patients with PHN are refractory to management. Recent evidence is emerging to support the use of topical local anesthetics for the treatment of PHN. Two small studies recently found topical lidocaine spray to be effective in treating paroxysmal pain attacks associated with PHN. Bupivacaine is a longer-lasting local anesthetic, and a film-forming formulation allows easy and durable application to the affected skin. Recent studies show that topical film-forming bupivacaine is safe and as effective as lidocaine for the treatment of PHN. PHN is an important though common complication of HZ and can cause long-lasting pain and disability. Current treatment for PNH is limited by efficacy and safety profiles of individual therapies. Recent evidence points to topical local anesthetics as an effective and safe alternative to conventional therapy. Film-forming bupivacaine may offer a durable and safe option for this otherwise difficult to treat syndrome.

Perineural injection of botulinum toxin-A in painful peripheral nerve injury - a case series: pain relief, safety, sensory profile and sample size recommendation

Objectives: Subcutaneous injection of botulinum toxin-A (sBONT-A) is a novel treatment for peripheral neuropathic pain. While its analgesic effects are well documented, this treatment is often not comfortable and fails in patients who show signs of sensory loss but rarely allodynia. There are some case reports about perineural BONT-A injection (pBONT-A) which could be an alternative approach. Here we present a retrospective, open label case series of pBONT-A's efficacy and safety regarding neurological consequences involving changes in somatosensory profiles of both responders and non-responders. Methods: Sixty patients (53 ± 13years, 77% males) with PNI were treated with pBONT-A after a test injection with a local anesthetic, which prompted distinctive pain relief. Quantitative sensory testing (QST; DFNS protocol) and pain intensity were assessed before and ≥7 days post pBONT-A injection. Definition of response: satisfactory pain reduction of ≥30% NRS (numerical rating scale: 0 = no pain, 10 = worst pain) for ≥4 days. Statistics: Paired t-test, Mann-Whitney U-test, χ² test. Results: A temporary weak paresis in one case was clinically verified. The QST -parameters remained unchanged, but patients with more frequent hyperalgesia signs reported less analgesia (p = .04). The pBONT-A injection prompted pain relief by 24.8% (NRS: 6.0 ± 1.7 vs. 4.5 ± 2.1; p < .0001); 57% (n = 34) were responders (NRS: 6.0 ± 1.6 vs. 3.4 ± 1.6, relief of 43.4%; p < .0001). Based on these results, we suggest that future parallel design trials on pBONT-A need to include at least 84 patients. Discussion: Ultrasound-guided pBONT-A injection seems to be a safe treatment leading to a sufficient pain relief for some months without sensory changes. Surprisingly, pBONT-A showed a pronounced analgesic effect also in patients without signs of hyperalgesia.

The use of 5% lidocaine medicated plaster for acute postoperative pain after gynecological surgery: A pilot randomized controlled feasibility trial

OBJECTIVES

To examine the feasibility and potential efficacy of 5% lidocaine medicated plaster for acute postoperative pain in a parallel, blinded, randomized controlled pilot trial.

METHODS

Twenty-eight women undergoing elective gynecological surgery with midline incisions were randomly allocated 5% lidocaine medicated patch (Lignopad) or placebo plasters. Postoperative pain at rest and on movement at 24 hours were the primary study endpoints, with secondary endpoints of postoperative pain within the first 48 hours, cumulative morphine consumption (mg), predicted peak flow rate (PFR) (%) and adverse effects. We assessed pain scores at rest and on movement using the visual analogue scale (0-100).

RESULTS

The lidocaine patch group had lower postoperative pain scores at rest at 24 hours (mean difference [MD] -15.1, 95% confidence interval [95% CI] -28.3 to -2.0; P = .024) but not on movement at 24 hours (MD -6.4, 95% CI -22.7 to 9.9; P = .445). Compared to placebo, lidocaine may slightly lower cumulative morphine consumption (mg) over time (MD -3.4, 95% CI -6.9 to 0.2; group*time interaction P = .065). The difference in improvement in the PFR over time after surgery between groups appeared small (group*time P = .0980). No adverse effects occurred.

CONCLUSIONS

Lidocaine patch may provide a clinically important reduction in postoperative pain intensity. A larger trial to confirm the efficacy and safety of lidocaine patch is feasible after modifying the inclusion criteria and collecting patient-centered outcomes, such as quality of recovery and patient satisfaction.

Evaluation of the Population Pharmacokinetic Properties of Lidocaine and its Metabolites After Long-Term Multiple Applications of a Lidocaine Plaster in Post-Herpetic Neuralgia Patients

Background and Objectives

Lidocaine 5% medicated plaster is the first lidocaine containing product for chronic use. As no previous investigations have been conducted to evaluate the population pharmacokinetics of long-term exposure to lidocaine 5% medicated plasters, further insights into the evaluation of the pharmacokinetic properties of lidocaine and its metabolites were needed for the assessment of its safety.

Methods

The population pharmacokinetic properties of lidocaine and its metabolites were evaluated after multiple applications of lidocaine 5% medicated plasters based on data collected for up to 14.5 months from two phase III clinical trials (up to 2.5 months in the first trial, and up to 12 months in a follow-up trial) in post-herpetic neuralgia patients. Modeling was performed using nonlinear mixed effects as implemented in NONMEM^® (nonlinear mixed-effect modeling) v.5. A stepwise forward inclusion and backward elimination procedure were used for covariate model building.

Results

The model provides reliable estimates of the pharmacokinetic behavior of lidocaine after medicated plaster application. It was validated using simulations and showed adequate predictive properties. Apparent Clearance was estimated to be 48 L/h after application of two or fewer plasters, whereas its value increased to 67 L/h after application of three plasters. Model-based simulations predicted no accumulation of lidocaine or any of its metabolites after long-term exposure of three simultaneous plasters up to 1 year. The variability explained by adding covariates into the model for the long-term exposures of lidocaine following one plaster or three simultaneous plaster applications was found to be very small with respect to the overall between-subject variability.

Conclusions

In conclusion, exposure to lidocaine after the application of the lidocaine medicated plaster was found to be primarily affected by the number of plasters simultaneously applied, i.e., it increased with the number of applied patches, but less than proportionally. No clinically relevant effect of other covariates was found to affect the exposure to lidocaine or its metabolites. As no accumulation was predicted by the model, long-term exposure to lidocaine and its metabolites is not expected to lead to any safety concerns in post-herpetic neuralgia patients.

Lidocaine 5%-medicated plaster (Versatis) for localised neuropathic pain: results of a multicentre evaluation of use in children and adolescents

The Lidocaine 5% plaster is licensed for the symptomatic relief of neuropathic pain associated with post-herpetic neuralgia in adult patients over 18 years of age. Studies in adults also demonstrate efficacy of Lidocaine 5% plasters in other neuropathic pain conditions. Case reports and experience suggested efficacy of Lidocaine 5% plasters in children and adolescents with localised neuropathic pain. Initiated by the Pain in Children Special Interest Group (PICSIG) of the British Pain Society, a 3-year prospective multicentre service evaluation was undertaken to document the usage and efficacy of the Lidocaine 5% plaster in paediatric patients being managed by paediatric pain teams in the United Kingdom. Five paediatric pain teams provided anonymised data pre-treatment and 3-6 months after commencing Lidocaine 5% plaster. Changes in pain score, function, sleep and continuing use were evaluated. Data were obtained for 115 patients; age range 5-18 years (mean: 12 years). Diagnosis and site of application varied. Benefit from use of a Lidocaine 5% plaster in an individual was deemed if two or more of the following were reported: reduction in pain score, functional improvement, sleep improvement and continuing use of Lidocaine 5% plaster. Benefit was recorded for 79 patients (69%); 32 patients were recorded as receiving no benefit and data were unavailable for 4 patients, and 7 patients reported minor skin reactions. This prospective service evaluation supports the efficacy of the Lidocaine 5% plaster in children and adolescents with localised neuropathic pain and confirms tolerability and safety. It is the opinion of the PICSIG of the British Pain Society that the Lidocaine 5% plaster should be considered early in the multidisciplinary management of localised neuropathic pain in children and adolescents.

Post-herpetic neuralgia - a review of current management and future directions

Post-herpetic neuralgia (PHN) is common and treatment is often suboptimal with less than half of patients achieving adequate 50% pain relief. As an area of unmet clinical need and as an archetype of neuropathic pain, it deserves the attention of clinicians and researchers. Areas covered: This review summarises the epidemiology, pathophysiology, risk factors and clinical features of varicella infection. It describes the current and possible future management strategies for preventing varicella infection and reactivation and for treating PHN. Expert opinion: A highly successful Varicella Zoster (VZV) vaccine has not been universally adopted due to fears that it may increase Herpes Zoster (HZ) incidence - and thus PHN - in older, unvaccinated generations. This is a controversial theory but advances in the efficacy of vaccines against HZ may allay these fears and encourage more widespread adoption of the VZV vaccine. Treatment of PHN, as for any neuropathic pain, must be multidisciplinary and multimodal. Advances in sensory phenotyping technology and genomics may allow more individualised treatment. Traditional research methodologies are ill-suited to assess the kind of complex interventions that are necessary to achieve better clinical outcomes in this challenging field.

Localized neuropathic pain: an expert consensus on local treatments

BACKGROUND

Pain localization is one of the hallmarks for the choice of first-line treatment in neuropathic pain. This literature review has been conducted to provide an overview of the current knowledge regarding the etiology and pathophysiology of localized neuropathic pain (LNP), its assessment and the existing topical pharmacological treatments.

MATERIALS AND METHODS

Literature review was performed using Medline from 2010 to December 2016, and all studies involving LNP and treatments were examined. A multidisciplinary expert panel of five pain specialists in this article reports a consensus on topical approaches that may be recommended to alleviate LNP and on their advantages in clinical practice.

RESULTS

Successive international recommendations have included topical 5% lidocaine and 8% capsaicin for LNP treatment. The expert panel considers that these compounds can be a first-line treatment for LNP, especially in elderly patients and patients with comorbidities and polypharmacy. Regulatory LNP indications should cover the whole range of LNP and not be restricted to specific etiologies or sites. Precautions for the use of plasters must be followed cautiously.

CONCLUSION

Although there is a real need for more randomized controlled trials for both drugs, publications clearly demonstrate excellent risk/benefit ratios, safety, tolerance and continued efficacy throughout long-term treatment. A major advantage of both plasters is that they have proven efficacy and may reduce the risk of adverse events such as cognitive impairment, confusion, somnolence, dizziness and constipation that are often associated with systemic neuropathic pain treatment and reduce the quality of life. Topical modalities also may be used in combination with other drugs and analgesics with limited drug-drug interactions.

Topical Treatments for Localized Neuropathic Pain

Purpose of Review

Topical therapeutic approaches in localized neuropathic pain (LNP) syndromes are increasingly used by both specialists and general practitioners, with a potentially promising effect on pain reduction. In this narrative review, we describe the available compounds for topical use in LNP syndromes and address their potential efficacy according to the literature.

Recent Findings

Local anaesthetics (e.g., lidocaine, bupivacaine and mepivacaine), as well as general anaesthetic agents (e.g., ketamine), muscle relaxants (e.g., baclofen), capsaicin, anti-inflammatory drugs (e.g., diclofenac), salicylates, antidepressants (e.g., amitriptyline and doxepin), α2 adrenergic agents (e.g., clonidine), or even a combination of them have been tested in various applications for the treatment of LNP. Few of them have reached a sufficient level of evidence to support systematic use as treatment options.

Summary

Relatively few systemic side effects or drug–drug interactions and satisfactory efficacy seem to be the benefits of topical treatments. More well-organized and tailored studies are necessary for the further conceptualization of topical treatments for LNP.

Lidocaine 5% medicated plaster for localized neuropathic pain in thoracic surgical patients

CONTEXT

Neuropathic pain is a common and distressing symptom in thoracic surgical patients. When it consistently presents with measurable sensory changes in a circumscribed area, neuropathic pain can be diagnosed as localized neuropathic pain (LNP).

OBJECTIVE

The purpose of this study was to report the efficacy of lidocaine 5% medicated plaster (Lido5%P) in the treatment of LNP in thoracic surgical patients.

METHODS

We retrospectively reviewed the records of sixteen cancer and noncancer thoracic patients treated with Lido5%P for LNP. Patients had been assessed before and during treatment with standardized forms and questionnaires for pain intensity, sleep quality, drug dosages and adverse events.

RESULTS

Treatment with Lido5%P yielded a significant and lasting improvement in pain symptomatology. In oncological patients as an add-on therapy, Lido5%P improved pain intensity and sleep quality, and delayed opioid dose escalation. In non-oncological patients as monotherapy or in association with antineuropathic drugs, Lido5%P attenuated LNP. No local or systemic adverse events were recorded.

CONCLUSIONS

Lido5%P was effective in relieving thoracic LNP, and was well tolerated.

The 5% Lidocaine-Medicated Plaster: Its Inclusion in International Treatment Guidelines for Treating Localized Neuropathic Pain, and Clinical Evidence Supporting its Use

When peripheral neuropathic pain affects a specific, clearly demarcated area of the body, it may be described as localized neuropathic pain (LNP). Examples include postherpetic neuralgia and painful diabetic neuropathy, as well as post-surgical and post-traumatic pain. These conditions may respond to topical treatment, i.e., pharmaceutical agents acting locally on the peripheral nervous system, and the topical route offers advantages over systemic administration. Notably, only a small fraction of the dose reaches the systemic circulation, thereby reducing the risk of systemic adverse effects, drug–drug interactions and overdose. From the patient’s perspective, the analgesic agent is easily applied to the most painful area(s). The 5% lidocaine-medicated plaster has been used for several years to treat LNP and is registered in approximately 50 countries. Many clinical guidelines recommend this treatment modality as a first-line option for treating LNP, particularly in frail and/or elderly patients and those receiving multiple medications, because the benefit-to-risk ratios are far better than those of systemic analgesics. However, some guidelines make only a weak recommendation for its use. This paper considers the positioning of the 5% lidocaine-medicated plaster in international treatment guidelines and how they may be influenced by the specific criteria used in developing them, such as the methodology employed by randomized, placebo-controlled trials. It then examines the body of evidence supporting use of the plaster in some prevalent LNP conditions. Common themes that emerge from clinical studies are: (1) the excellent tolerability and safety of the plaster, which can increase patients’ adherence to treatment, (2) continued efficacy over long-term treatment, and (3) significant reduction in the size of the painful area. On this basis, it is felt that the 5% lidocaine-medicated plaster should be more strongly recommended for treating LNP, either as one component of a multimodal approach or as monotherapy.