Postherpetic Neuralgia

The goal of this clinical trial is to assess the efficacy and safety of Y-4 in patients with postherpetic neuralgia(PHN). The main questions it aims to answer are: The efficacy and safety of Y-4 to treat PHN compared with pregabalin. Researchers will analyze data from different groups, includes Y-4 group and pregabalin group , to see efficacy of Y-4 and If drug Y-4 is safe and tolerate in the patients with PHN. Participants will : * Take Y-4 (1w titration period: 75 mg pregabalin +18.75 mg riluzole, 12w fixed dose period: 150 mg pregabalin +37.5 mg riluzole, 1w drug withdraw period: 1w titration period: 75 mg pregabalin +18.75 mg riluzole) or pregabalin(75 mg for 1w titration period , 150 mg for 12w fixed dose period ,75 mg for 1w drug withdraw period) twice a day for 14 weeks after run-in period (placebo) lasting for 1 week. * Visit the hospital according to the follow-up schedule agreed upon with your doctor. contact the research staff as soon as possible to reschedule when unable to attend the scheduled study visit. * Use investigational products as directed by the doctor and undergo the related treatment. * Inform their investigators of any changes in their health, including any side effects or symptoms, whether or not they believe these changes are related to the trial medication, as well as any new medications they are using or wish to use, or any changes in the dosage of medications they have already taking. * Use reliable contraceptive methods , such as abstinence, intrauterine devices, double barrier methods (e.g., condom with spermicide or condom with a diaphragm containing spermicide), contraceptive implants, or oral contraceptives (except if the partner is infertile) during the study period and within one month after the study is completed. * Must inform investigators immediately if they or their partner become pregnant during the study. * Be sure to inform other doctors being consultant that you are participating in this clinical study. * Restrict medication use and treatment during the study.

This is a prospective, single-arm, open-label, pilot clinical study to evaluate the efficacy and safety of topical 10% high-concentration 35 kDa hyaluronan (HA35) gel in subjects with herpes zoster-associated pain (ZAP). Eligible participants will receive a single topical application of the study gel. The primary objective is to assess rapid pain reduction within 2 minutes and 24hours after application. Secondary objectives include evaluation of analgesic duration, local tolerability, erythema improvement, and overall safety throughout the observation period. This is a minimal-risk, non-pharmacological supportive care intervention.

Postherpetic neuralgia (PHN) is the most common complication of herpes zoster (HZ) and represents a major clinical challenge due to its chronicity and impact on quality of life. Current treatments for acute HZ pain have limited efficacy in preventing PHN, highlighting the need for effective preventive strategies targeting early pathophysiological mechanisms. Venlafaxine as a plausible and clinically relevant candidate for early intervention to prevent the transition from acute HZ pain to PHN.

This observational study aims to compare the effectiveness of ultrasound-guided erector spinae plane (ESP) block and transcutaneous radiofrequency (RF) treatment in patients with postherpetic neuralgia. Pain intensity and neuropathic pain characteristics will be evaluated using the Visual Analog Scale (VAS) and the Self-Leeds Assessment of Neuropathic Symptoms and Signs (S-LANSS) score.

Postherpetic neuralgia (PHN) is a chronic pain syndrome that may be resistant to treatment and can lead to physical and social disability as well as psychological disturbances, persisting for years in some patients. Varicella zoster virus remains latent in the sensory neurons of individuals who have previously had chickenpox. Reactivation of the latent virus results in herpes zoster. Herpes zoster typically begins with dermatomal pain, followed within a few days by the development of characteristic dermatomal skin rashes. These cutaneous lesions usually resolve within 2-4 weeks; however, pain may persist even after the rash has healed. There is variability in the literature regarding the definition of PHN. The development of PHN is associated with increased central neuronal sensitization, reduced inhibitory neuronal function, inflammation and nerve injury in the peripheral nervous system, and abnormal neural transmission following nerve damage. PHN is the most common complication of herpes zoster and occurs in approximately 9-19% of affected patients. Its incidence increases with age, occurring in about 2% of patients under 50 years of age, approximately 20% of those over 50 years, and nearly 35% of patients over 80 years of age. Various treatment options are available for the management of PHN-related pain, including pharmacological and interventional approaches. Systemic agents include tricyclic antidepressants, calcium channel alpha-2-delta ligands, serotonin-norepinephrine reuptake inhibitors, and opioids, while topical treatments include lidocaine and capsaicin. Interventional treatment options for PHN include epidural and intrathecal injections, sympathetic nerve blocks, erector spinae plane block, subcutaneous injections, and spinal cord stimulation.

Pharmacotherapy is the cornerstone of Postherpetic Neuralgia (PHN) management. First-line treatments for PHN include antiviral agents (e.g., acyclovir, valacyclovir, famciclovir, and brivudine), centrally acting antiepileptic drugs (pregabalin and gabapentin), antidepressants (duloxetine and venlafaxine), and peripherally acting sodium-channel blockers (lidocaine patches). In recent years, substantial progress has been made in the prevention and treatment of PHN, including early and active antiviral therapy (acyclovir, valacyclovir, famciclovir, brivudine, etc.), analgesic therapy (calcium-channel modulators such as pregabalin and gabapentin; tricyclic antidepressants such as amitriptyline; and opioid analgesics), interventional procedures (e.g., radiofrequency modulation and spinal cord stimulation), and vaccination. Nevertheless, clinical outcomes remain unsatisfactory, with the incidence of refractory PHN still exceeding 50%. Adverse effects associated with certain first- and second-line medications (such as antidepressants and anticonvulsants), as well as the potential risk of opioid dependence, markedly reduce treatment adherence. This situation has compelled clinicians to continually seek new and effective therapeutic approaches for PHN. Non-invasive transcranial stimulation, as an emerging noninvasive neuromodulation technique, enables targeted modulation of deep brain structures. Animal studies have demonstrated that it can noninvasively regulate neuronal firing in deep regions and induce long-term plasticity, while offering relatively high spatial selectivity and tissue penetration. These features suggest broad clinical potential in chronic pain and affective disorders.

This trial is investigating the acceptability and efficacy of PFM-guided cortical stimulation for the treatment of central neuropathic pain.

The goal of this clinical trial is to evaluate safety and efficacy of percutaneous peripheral nerve stimulation in patients with peripheral neuropathic pain. The main questions it aims to answer are: 1. The efficacy of percutaneous peripheral nerve stimulation in patients with peripheral neuropathic pain 2. The safety of percutaneous peripheral nerve stimulation in patients with peripheral neuropathic pain Participants are going to undergo procedure that implant peripheral nerve stimulation electrode produced by Jiangsu CED Medtech Co., Ltd. Then the subjects, whose VAS scores decrease more 30% than baseline level, are classified into two groups randomly. One of the group receiving active stimulation called trial group and another receiving placebo stimulation called control group. All subjects are required to make their own subjects' pain diary to record VSA score before and after implantation until at the end of follow-up. Also, participants are asked to report use of analgesic medications, number of awakenings and adverse events. Researchers will compare pain scores between the two groups to see if peripheral nerve stimulation is effective to patients with peripheral neuropathic pain.

To investigate the effectiveness of ultra-Sound guided Erector spinae block (ESB) with Betamethasone as an adjuvant to standard medical protocol in the management of truncal chronic post herpetic neuralgia.

To assess the 1-week effects and safety of esketamine in combination with pregabalin and duloxetine to relieve pain in patients with postherpetic Neuralgia(PHN).

This trial's primary objective is to compare the analgesic efficacy of esketamine in combination with pulsed radiofrequency (PRF) of dorsal root ganglion(DRG) against that of PRF monotherapy in patients with postherpetic neuralgia(PHN).

Based on the inclusion and exclusion criteria, patients with head and face PHN who met the requirements were selected as trial subjects, and the efficacy was clarified in a randomized controlled design trial. The visual analog score VAS was used as the primary evaluation index, and the depression self-assessment scale score , Hamilton depression scale, Pittsburgh sleep quality index scale, and quality of life evaluation scale (SF-36) were used as the secondary evaluation indexes, and oral pregabalin was used as the control group, and the subjects in the pregabalin and the plexus superficial stabbing combined with electroacupuncture groups were observed respectively at the time of Before treatment, immediately after the first treatment, after 2 days of treatment, after 2 weeks of treatment, after 4 weeks of treatment, after 1 month of follow-up after the end of treatment and after 2 months of follow-up after the end of treatment.