Pain Management of Herpes Zoster

Abstract

Herpes zoster HZ is a disease triggered by the reactivation of latent varicella zoster virus VZV in spinal or cranial sensory ganglia, and is characterized by a painful vesicular eruption in the affected dermatome. Postherpetic neuralgia PHN is a chronic, neuropathic pain that can persist long beyond resolution of visible cutaneous manifestations which is often resistant to current analgesic treatments. The lifetime prevalence of herpes zoster is approximately -% and about -% of these patients develop PHN depending on its definition. Clinical experience has shown that PHN often develops in cases of inadequate initial pain management resulting in increased pain intensity. This review provides an overview of the treatment options for HZ and PHN, focusing on the therapeutic modalities of pain management. The primary objectives of management of HZ are to inhibit viral replication, relieve pain, and prevent associated complications, such as PHN. General treatments for acute HZ are combination of antiviral therapy with a short course of corticosteroids at the onset of the disease in conjunction with an effective control of acute pain, including nonsteroidal anti-inflammatory drugs, acetaminophen, opioids, and anticonvulsants such as gabapentin or pregabalin. Treatment of PHN is often resistant to the current pharmacologic methods. Therefore, a multimodal analgesic treatment regimen including topical lidocaine and capsaicin, systemic therapies, and the interventional treatments is necessary to alleviate pain and its effect on quality of life. As the incidence of HZ increases with age, the number of patients with HZ and PHN may increase in the future considering the gradual aging of the general population. Appropriate management of HZ can reduce the duration and intensity of pain from HZ, and prevent the development of PHN. In addition, prophylactic zoster vaccination can prevent or reduce the incidence of HZ and PHN. Further efforts are needed to minimize pain of the patients suffering from HZ and PHN as it affects the quality of life in the aspect of both physical and psychological impairments. . IntroductionHerpes zoster HZ is caused by reactivation of latent varicella zoster virus VZV in sensory dorsal root ganglion cells, and is characterized by a painful, unilateral vesicular skin eruption in the affected dermatome. The lifetime risk of HZ is approximately -% [ -]. The incidence of herpes zoster is . -. per person-years in all ages and -per personyears in persons over years of age in European and North American, according to studies [ -]. Classically, the skin eruption is preceded by one to several days of stabbing, episodic or continuous pain in the affected area, although the pain may develop simultaneously or even following the skin eruption. Herpes zoster-associated pain tends to resolve over time, but approximately -% of herpes zoster patients develop post-herpetic neuralgia PHN that can persist several years beyond resolution of visible cutaneous eruptions. The frequency of PHN has been reported to ...

Trigeminal Herpes Zoster: A Brief Review

“…It has a bioavailability of 15 -30% and a half-life of three hours. When given within 72 hours of rash, it decreases pain and promotes healing, but the intensity of postherpetic neuralgia is not reduced (3,22). The drug is well tolerated orally, but some cases of headache, nausea, malaise, and CNS effects have been reported, whereas rashes, sweating, hypotension, and emesis when given intravenously (21).…”

“…A maximum of three patches can be applied for 12 hours a day over the affected area, and its efficacy is noted after 7 -10 days of treatment (23,24). Capsaicin, an alkaloid and an active neuropeptide agent derived from hot chili peppers, can be applied at concentrations of 0.025 and 0.075% as a topical agent (22,23). Also, PHN, a typical complication of HZ, can be managed systemically by three classes of medication: Anticonvulsants, antidepressants, and opioid analgesics.…”

“…In contrast, pregabalin, a potent gabapentinoid and structural analog of GABA is an ion channel modulator with rapid analgesic actions and fewer side effects. Depending on effectiveness and tolerability, pregabalin can be given 100 -150 mg per day as a starting dose as a starting dose to a maximum of 600 mg per day (22). Tricyclic antidepressants like amitriptyline, nortriptyline, and desipramine inhibit spiral neurons involved in nociceptive perception by blocking the neuronal uptake of noradrenaline and serotonin (22).…”

“…Opioid analgesics also alleviate the PHN pain by binding to opioid receptors such as µ, K, δ, and nociceptors present in the central and peripheral nervous system but cannot be used as the first-line treatment due to tolerance and concerns related to its misuse. Opioids have specific side effects like cardiorespiratory dysfunction, sedation, nausea/vomiting, histamine release, and constipation as significant side effects in elderly patients (22). Non-pharmacological pain management methods like nerve blocks, TENS, and botulinum toxin can be used in patients not relieved from pharmacological approaches.…”

“…Non-pharmacological pain management methods like nerve blocks, TENS, and botulinum toxin can be used in patients not relieved from pharmacological approaches. Sympathetic nerve blocks can be used in treating patients with acute HZ (22,24). Besides, TENS is an adjunctive therapy that transiently relieves pain utilizing electric currents produced by a device to stimulate nerves at a vigorous intensity (22,24).…”