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SummaryPostherpetic Neuralgia (PHN) is a form of nerve pain that persists after an acute case of shingles. Shingles is an acute viral infection of the peripheral and central nervous system by the Herpes Zoster (HZ) virus, usually affecting a single spinal nerve root. After causing chicken pox in childhood, the HZ virus lies dormant in the dorsal root ganglion cells of the spinal nerves, constantly being suppressed by the immune system. During times of stress (infection, trauma) or immunosuppresion, the virus multiplies being no longer suppressed.Pain is defined as ”unpleasant sensory and emotional experience associated with actual or potential tissue damage”. Painful stimuli activate specific pain receptors which transform pain information into an electrical signal which is conducted, centrally. Considering the different causes and types of pain, as well as its nature and intensity. Management can require an interdisciplinary approach. The elements of this approach include treating the underlying cause of pain, pharmacological and non-pharmacological therapies, and some invasive (surgical) procedures.There are numerous treatment options for postherpetic neuralgia. Overall, the treatment is directed at the palliation of pain and at improving the patient’s quality of life. Even though postherpetic neuralgia is usually self-limiting in that the condition can resolve within one year, approximately 10-20% of patients will have chronic pain that does not resolve, pharmacotherapy of PHN may include multiple modalities such as topical preparations, antidepressants, antiepileptic drugs, opioids and a number of empirical treatments.Tricyclic antidepressants [such as amitriptyline (Elavil) and nortriptyline (Pamelor)] are effective and important players in the pharmacotherapy of PHN. These agents block the reuptake of noradrenaline and serotonin and, thus, may relieve pain by increasing the inhibition of spinal neurons involved in pain perception.Antiepileptic drugs [such as gabapentin (Neurontin) and carbamazepin (Tegretol)] used to treat epilepsy and seizures. In recent years, the antiseizure drug gabapentin has become available and it is widely prescribed for PHN. It has been shown to be effective and safe with few side effects. Also, gabapentin does not interact with any other medication making it a good choice for many patients.Opioids (such as oxycodone, morphine and methadone) have not been well accepted for the management of chronic intractable neuropathic pain, not only because of widespread misconceptions about their safety and efficacy, but also because of patient’s and health care professionals’ fears about issues such as tolerance, physical dependence and addiction.Topical treatment is a good starting point for patients with PHN in whom systemic treatment and its associated adverse events are undesirable or contraindicated.Non-drug therapy such as various types of nerve blocks and other surgical therapies have been applied in the treatment of PHN but none have been documented in a controlled manner to be effective for PHN. Immediate pain reduction may occur following a somatic or sympathetic nerve block.Safe long-term pain control may be provided with the implantation of an intrathecal pump for the administration of a variety of agents (e.g. opioids and local anaesthetics). Also, patients may get pain relief from therapies that stimulate the nerves, such as Transcutaneous Electrical Nerve Stimulation (TENS) which send very small amounts of electrical current to the skin through electrodes that are stuck to the skin.Acupuncture involves the placement and manipulation of needles at various points in the body for the treatment of pain. Fundamental to the practice of classical acupuncture is the concept of qi. The energy flow that connects body structures and systems flows through a network below the skin. This network is a set of pathways or meridians that run longitudinally in and around the body. The meridians emerge at the surface of the body at certain places, known as acupuncture points which are stimulated to balance the circulation of energy.Different acupuncture techniques have been used to treat early cases of herpes and postherpetic neuralgia.
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