Treatment of patients with neuropathic pain and provision of drug information by clinical pharmacists

Abstract Patient's satisfaction with healthcare services has an influence on pain management, which can be improved by patient education. Therefore, this study was aimed at identifying primary care health service opportunities in the treatment of neuropathic pain and assessing patients' satisfaction with the provision of drug information by clinical pharmacists. This was a cross- sectional, prospective study conducted at a pain unit during March-May 2017. Patients aged >18 years; diagnosed with neuropathic pain; and who used amitriptyline, gabapentin, pregabalin, or duloxetine were included. They were verbally informed about drug treatment by a clinical pharmacist, and their satisfaction was evaluated after 1 month. In all, 90 patients were included. The median duration for which the patients experienced pain until hospital admission was 3.6 years; furthermore, this duration was longer among women (p < 0.05). However, the median time to seeking advice from doctors was 3 months. The patients (15.6%) were less likely to admit pain unit initially and 46.7% had visited different units before being admitted to a pain unit. More than 95% of the patients indicated that they had received information from a pharmacist at a clinic and were satisfied with the provision of information (median duration, 8.5 min). Thus, the involvement of pharmacists in multidisciplinary pain management may help improve health- related outcomes at hospitals and/or in community care settings

A two-case report of successful treatment with pregabalin for refractory chemotherapy-induced hiccups

<b>Purpose</b>: Hiccups are a symptom that often appear in lung cancer patients during medical treatment. Although various drugs and non-pharmacologic therapies are used to treat them, they often are not effective. We report 2 cases of successful treatment for refractory hiccups due to chemotherapy for lung cancer using pregabalin. <b>Case report</b>: Both patients had advanced squamous lung cancer. That in case 1 was treated using chemotherapy with carboplatin and paclitaxel, while the case 2 received nedaplatin and irinotecan. Hiccups occurred and became exacerbated during chemotherapy in both, and were considered to be induced by the anticancer drugs. Separate treatments with metoclopramide, chlorpromazine, and gabapentin did not have any effect, whereas immediate improvement was seen after taking pregabalin in both cases. <b>Conclusion</b>: Pregabalin, often used as an adjuvant analgesic, controls excessive neuronal excitement. In the present cases, effective relief of refractory hiccups was seen.

Successful elimination of intractable lower limb neuropathic pain by pelvic tumor invasion using ultrasound-guided sciatic nerve block

We report a case whose left lower limb neuropathic pain accompanied by pelvic tumor invasion was remarkably eliminated by ultrasound-guided sciatic nerve block. <b>Case report</b>: The subject was a sixty year old male. Pharmacological therapy was given according to the WHO analgesic ladder, but his left lower limb pain failed to respond to drugs. His intractable lower limb neuropathic pain was alleviated by ultrasound-guided sciatic nerve block. Drug delivery can be achieved with a percutaneous catheter and a disposable infusion pump. Infusions were run at 5mlh<SUP>-1</SUP> with 0.1% ropivacaine. <b>Conclusion</b>: Neuropahic pain is sometimes hard to be controlled only by opioids or adjuvant analgesics, but there is a possibility of providing pain relief by combination use with nerve blocks. Interventional techniques can be highly effective but also have the potentiality to produce significant adverse effects. Many patients have factors which would be considered a near absolute contra-indication to the use of nerve blocks such as immuno-compromise or impairment of coagulation. Skillful application of peripheral neural blockade with ultrasound imaging broadens the options for providing optimal pain management. Palliat Care Res 2011; 6(1): 313-315

Effectiveness and long term safety of gabapentin in the management of neuropathic pain of terminally-ill cancer patients

<b>Purpose</b>: This study is aimed at the evaluation of the effectiveness and safety of gabapentin for the management of cancer-related neuropathic pain in terminally-ill cancer patients. <b>Methods</b>: We investigated terminally-ill cancer patients prescribed gabapentin for the management of cancer-related neuropathic pain, from November 200X to October 200X+2. We assessed average daily pain on the numerical rating scale (NRS) before administration, after one week, and while on a stable dose. <b>Result</b>: 44 patients were enrolled during this period and 19 patients completed the study. The medication and the survival period on average were 52.0 and 67.2 days, respectively. The average gabapentin daily dose after one week was 358 mg. The average period needed to reach a stable dose was 11.6 days and the average stable daily dose was 463 mg (male 620 mg, female 289 mg). The mean NRS decreased from 5.7 (before) to 2.1 (after one week, <I>p</I><0.001) and 1.9 (stable dose, <I>p</I><0.001), respectively. 57.9% of patients showed side effects, somnolence in 52.6%, delirium in 5.3%, tremor in 5.3%. <b>Conclusion</b>: Gabapentin can be expected to be effective and safe for managing cancer-related neuropathic pain for a long period even when in critical condition through careful titration. Palliat Care Res 2011; 6(1): 101-108

Current pharmacological management of chronic pain

Chronic pain is associated with disabling physical and emotional symptoms. Patients with chronic pain utilize more health services, have an impaired sense of well-being and frequently experience anxiety or depression. Unfortunately, treatment for chronic pain is not always correctly targeted, which leads to a reduced quality of life. Treatment of chronic pain involves a comprehensive approach using medication and functional rehabilitation. The usual approach for mild to moderate pain is to start with nonopioid analgesics. Also, trying antidepressant drugs for sleep loss and gabapentin for neuropathic pain or fibromyalgia is appropriate. For moderate to severe chronic pain, opioid analgesics can be used without any serious side effects if adequately used at the right dosage. It is important to provide guidance on the safe use of analgesics and other psychoactive drugs. Dosing of acetaminophen should be limited to avoid liver toxicity, and topical analgesics are preferred for focal pain. Full-dose nonsteroidal anti-inflammatory drugs should not be used for more than short periods, in order to avoid gastrointestinal, renal, and cardiovascular complications. Mechanisms of analgesia, drug selection, and recommendations for clinical usage for the management of chronic pain are reviewed in this paper.

Use of gabapentin was effective to improve cancer pain associated with extensive collapse of upper cervical vertebrae due to multiple myeloma: a case report

<b>Purpose</b>: Some patients with cancer pain are relatively less responsible to opioids, and require other strategies to improve the balance between analgesia and adverse effects. In those patients, the usage of some adjuvant analgesic drugs is recommended with opioid analgesics according to the first step of the WHO ladder for cancer pain relief. Recently, the efficacy of gabapentin for several cancer-related neuropathic pain has been reported. <b>Case report</b>: We present the case of a 64-years old female patient who had extensive vertebral bone destruction of C1-C2 due to metastasis of multiple myeloma, complicated with acute tetraplegia. Invasion to the retropharyngeal space by tumor enlargement seemed to increase the risk of upper airway obstruction. When our palliative care team first met her, she was suffering from the severe nape pain with allodynia at her right shoulder and incurable headache, refractory to intravenous morphine hydrochloride administration of 100mg/day (numerical rating scale; NRS 7/10). Her chief physician was negative against the dose escalation of the opioid analgesics, because of the risk of respiratory depression. Significant analgesic effect (NRS 3/10) was immediately achieved with oral gabapentin 900mg/day on day1. On day5, after gabapentin was increased up to 1,800mg/day, her nape pain was remarkably reduced to NRS 1/10, and no adverse effect was reported. <b>Conclusion</b>: For patients who are relatively naïve to increase of opioid analgesics, the supplementary use of adjuvant analgesic drugs would be favorable to both objectives; fewer adverse effects and reduction of the pain. Palliat Care Res 2009; 4(1): 301-306

Effect of oral ketamine on neuropathic pain

<b>Purpose</b>: Ketamine is effective on neuropathic pain that is difficult to respond to opioids among cancer pains, due to its N-methyl-D-aspartate (NMDA) receptor antagonism action. The purpose of this study was to evaluate the effect of oral ketamine on neuropathic pain. <b>Methods</b>: We retrospectively investigated the dosage and the administration period of oral ketamine in 31 patients for one year from December 2004. <b>Results</b>: Pain-relief was achieved in 22 of 31 patients, the average of initial dose was 107.3mg/day and the average administration period was 63 days. Seven patients discontinued oral ketamine within 7 days because of nausea/ vomiting (4 patients) or drowsiness (3 patients). Two patients had no sufficient pain-relief. <b>Conclusion</b>: This experience suggests that oral ketamine is effective on the management of neuropathic pain. Palliat Care Res 2008; 3(1): 216-220

Gabapentin for the Management of Various Neuropathic Pain Syndromes / 대한마취과학회지

BACKGROUND: Anticonvulsant agents have been used and found to be effective for the treatment of neuropathic pain. Even though it is rare, they can have very serious side effects and therefore the search for more selective drugs with fewer side effects is justified. This study was conducted to evaluate the newly introduced anticonvulsants, gabapentin, for various neuropathic pain syndromes in the Korean population. METHODS: According to individual diagnostic group as diabetic neuropathy, postherpetic neuralgia, chronic back pain with radiating pain, there were 20 patients per group. Patients have been stabilized in their analgesic regimen at least four weeks prior to enrollment in the study. An anticonvulsant, if taken, was discontinued for four weeks for wash-out. Pretreatment baseline pain scores (visual analog scale and a pain intensity score) were obtained. Oral administration of gabapentin 300 mg was initiated in all groups and doses were given from 300 mg per day with gradual titration over two weeks 1) to the maximum of 2400 mg per day, 2) to the onset of intolerable side effects, and 3) to the onset of analgesic effect. At two weeks follow-up visit, visual analog scale, pain intensity scores, pain improvement scores judged by family, drug efficacy, tolerability and overall evaluation were assessed. The incidence of side effects, cell blood count and chemistry were also obtained. RESULTS: After two weeks of treatment, the visual analog scale and pain intensity scores improved in all study groups and no patients experienced aggravation. These findings were objectively reflected in pain improvement scores observed by family members. In drug efficacy, tolerability and overall evaluation, the majority of patients scored as good or excellent. There were no reports of serious side effects. Minor side effects were spontaneously subsided even with continuation. CONCLUSIONS: Gabapentin, a newer anticonvulsant, appears to be effective as an adjunctive analgesic for the management of various neuropathic pain syndromes with minimal side effects.