Pharmacological Management of Neuropathic Pain: Current Trends and Possible Approaches

Abstract

Context: Neuropathic pain (NP) is a chronic debilitating painful condition with complex pathophysiology and inadequate treatment. Conventional pharmacological approaches and currently available drugs only provide marginal pain relief and cause significant adverse effects. The present manuscript is an attempt to summarize the existing data and possible pharmacological approaches available for NP.Evidence Acquisition: Information was collected from Google Scholar, Cochrane and PubMed databases, Scopus and directory of open access journals. Neuropathic pain, chronic pain, diabetic neuropathy, pathophysiology and current recommendations were the terms used to search the literature. Data from relevant animal and randomized controlled studies were selected to get the up to date information of the currently available pharmacological approaches. A note on future approaches was added based on the recent animal and human studies. Results:The current review made a significant attempt to focus on the mode of action, required dosage, advantages and the side effect profiles of currently available drugs used, or in investigational phases and their possible combinations to manage NP. Efforts are made to cover arise of NP because of diabetes and its management. At the end, authors made an attempt to cover the various therapeutic options that are currently explored for future drug development. Conclusions:The available pharmacological approaches are effective on one or other types of chronic pain. But the inadequate pain relief and limitations with each class of drugs raises the need to develop better therapeutic approaches and also understand the pathology better. The present review may be helpful to researchers intending to focus on newer therapeutic strategies and targets to manage NP.Keywords: Chronic Pain, Antidepressants, Anti-Epileptics, Opioids, Therapeutic Management ContextNeuropathic pain (NP) is a severe debilitating form of pain which originates as a consequence of lesion or disease pertaining to somatosensory system. The term lesion refers to the actual/potential damage of neurons identified via laboratory diagnostic procedure, whereas the term disease refers to the known cause for the lesion. NP is a clinical description which helps to identify the possible underlying causes. Etiology of NP ranges from traumatic nerve damage/compression, diabetes, cancer and its chemotherapy, viral infections such as HIV, alcohol and other toxin exposure, surgical amputations, etc. Furthermore, pain originated from a lesion or disease in central or peripheral somatosensory nervous system leads to the categorization of NP into central NP or peripheral NP, respectively. NP is associated with a wide range of sensory changes as described in Table 1 (1). Currently available drugs provide only marginal pain relief and are associated with various adverse effects.Therefore, understanding the current knowledge about complex pathology of NP and available drugs helps the researchers to rationalize the therapeutic approaches. This also...

Selected pathobiological features and principles of pharmacological pain management

“…13,18,19 Inflammatory pain is best treated with paracetamol, aspirin, or other nonsteroidal anti-inflammatory drugs (NSAIDs) and—when necessary—by opioids; in contrast, chronic pain is typically treated with either tricyclic antidepressants (e.g., amitriptyline) or anticonvulsants (e.g., gabapentin), or a combination of the two. 12,20–23…”

“…13,18,19 Inflammatory pain is best treated with paracetamol, aspirin, or other nonsteroidal anti-inflammatory drugs (NSAIDs) andwhen necessary-by opioids; in contrast, chronic pain is typically treated with either tricyclic antidepressants (e.g., amitriptyline) or anticonvulsants (e.g., gabapentin), or a combination of the two. 12,[20][21][22][23] Pain is a subjective experience. Under similar circumstances, patients with comparable states of general health who experience noxious stimuli of similar intensities will report pain of different degrees of intensity, and each patient may require different treatment to achieve pain relief.…”

The effect of pregabalin and duloxetine treatment on quality of life of breast cancer patients with taxane-induced sensory neuropathy: A randomized clinical trial

“…Pregabalin was received approval from food and drug administration in the treatment of DPN and postherpetic neuralgia (PHN). [ 29 ] The dosage of 150–600 mg daily of pregabalin was tolerable which led to the improvement of pain and sleep difficulties relating to DPN or PHN. [ 30 ] In the present study, we used 75 mg/days of pregabalin in the 1 st week followed by 75 mg twice a day for 5 weeks to improve the drug's tolerability.…”

Analgesic Action by Neuroleptics in Diabetic State

“…This is probably due to improvement of descending monoaminergic inhibitory pathways by blocking serotonin and noradrenalin reuptake centrally. Alpha-adrenergic, muscarinic cholinergic, histaminergic and blockade of calcium and sodium channels are also reported [19].…”