ABSTRACT
OBJECTIVE: To assess the efficacy and safety of the topical 5% lidocaine medicated plaster in the treatment of localized neuropathic pain. STUDY DESIGN: This was a case series at an Austrian pain clinic, using retrospective analysis. PATIENTS AND METHODS: Data of 27 patients treated for localized neuropathic pain with the 5% lidocaine medicated plaster were retrospectively analyzed. Assessment included changes in overall pain intensity, in intensity of different pain qualities, and of hyperalgesia and allodynia, and changes in sleep quality. RESULTS: Patients (17 female, ten male; mean age 53.4±11.4 years) presented mainly with dorsalgia (16 patients) or postoperative/posttraumatic pain (seven patients); one patient suffered from both. The mean overall pain intensity prior to treatment with lidocaine medicated plaster was 8.4±1.2 on the 11-point Likert scale. In the majority of cases, the lidocaine plaster was applied concomitantly with preexisting pain medication (81.5% of the patients). During the 6-month observation period, overall mean pain intensity was reduced by almost 5 points (4.98) to 3.5±2.6. Substantial reductions were also observed for neuralgiform pain (5 points from 7.9±2.6 at baseline) and burning pain (3 points from 5.2±4.1). Sleep quality improved from 4.6±2.6 at baseline to 5.5±1.8. Stratification by pain diagnosis showed marked improvements in overall pain intensity for patients with dorsalgia or postoperative/posttraumatic pain. The lidocaine plaster was well tolerated. CONCLUSION: Overall, topical treatment with the 5% lidocaine medicated plaster was associated with effective pain relief and was well tolerated.
ABSTRACT
OBJECTIVE: To assess treatment with the 5% lidocaine medicated plaster for peripheral neuropathic pain after disk herniation. STUDY DESIGN: Case series, single center, retrospective data. PATIENTS AND METHODS: Data of 23 patients treated for neuropathic pain with the lidocaine plaster for up to 24 months after a protrusion or prolapse of the cervical, thoracic, or lumbar vertebral disks were retrospectively analyzed. Changes in overall pain intensity, in intensity of different pain qualities and of allodynia and hyperalgesia were evaluated. RESULTS: Patients (14 female/nine male, mean age 53.5 ± 10.4 years) presented with radiating pain into the abdomen, back, neck, shoulder, or legs and feet with a mean pain intensity of 8.3 ± 1.5 on the 11-point Likert scale. Mean treatment duration was 7.6 months; 52% of the patients received lidocaine plaster as monotherapy. At the end of the observation, mean overall pain intensity had been reduced to 3.1 ± 1.8. All other parameters also improved. The treatment was well tolerated. CONCLUSION: These results point to a safe and effective treatment approach with 5% lidocaine medicated plaster for localized neuropathic pain related to disk herniation. However, owing to the small sample size, further investigation in a larger-scale controlled trial is warranted.
ABSTRACT
Activation of opioid receptors on peripheral sensory nerve terminals by opioid peptides that are produced and released from immune cells can result in inhibition of inflammatory pain. This study tests the hypothesis that postoperative pain is attenuated endogenously through a local sympathetic neurotransmitter-activated release of opioids in patients undergoing knee surgery. We examined the expression of opioid peptides and adrenergic receptors in cells infiltrating inflamed synovial tissue and we hypothesized that intra-articular (i.a.) administration of the adrenergic receptor antagonist labetalol will increase postoperative analgesic consumption and/or pain intensity in these patients. In a double-blind, randomized manner, 75 patients undergoing therapeutic knee arthroscopy received i.a. placebo (20 ml saline) or labetalol (2.5 or 5 mg in 20 ml saline) at the end of surgery. Postoperative pain intensity was assessed by visual analog and verbal rating scales at rest and on exertion, and by the consumption of morphine via patient-controlled analgesia. Synovial biopsies were taken during the operation for double-immunofluorescence confocal microscopy studies. Alpha(1)- and beta(2)-adrenergic receptors were co-expressed in opioid peptide-containing cells. No significant difference was seen in pain scores, but patients receiving 2.5 mg labetalol requested significantly higher amounts of morphine. These findings are consistent with the notion that surgical stress induces sympathetically activated release of endogenous opioids from inflammatory cells and subsequent analgesia via activation of peripheral opioid receptors.
Subject(s)
Adrenergic alpha-1 Receptor Antagonists/adverse effects , Adrenergic beta-Antagonists/adverse effects , Analgesics/administration & dosage , Knee Injuries/surgery , Labetalol/adverse effects , Pain, Postoperative/drug therapy , Adrenergic alpha-1 Receptor Antagonists/administration & dosage , Adrenergic beta-Antagonists/administration & dosage , Adult , Aged , Aged, 80 and over , Female , Humans , Injections, Intra-Articular/methods , Knee Injuries/metabolism , Labetalol/administration & dosage , Male , Middle Aged , Pain, Postoperative/metabolism , Young AdultABSTRACT
OBJECTIVES: To compare the efficacy and tolerability of transdermal buprenorphine in elderly patients and 2 younger populations, all requiring analgesic treatment for moderate-to-severe chronic pain. METHODS: Three equally sized age-groups (A>/=65, n=30; B=51 to 64, n=27; C=50 y, n=25) were examined during 28-day treatment periods to detect potential differences in responsiveness (pain intensity, rescue medication, sleep duration) to the transdermal opioid. RESULTS: Distribution of pain causing diagnoses was comparable between age-groups, predominantly musculoskeletal disorders (65% of all diagnoses), diseases of the nervous system (13%), injuries (8%), and cancer (5%). Mean buprenorphine patch doses were 35, 50, and 40 mug/h (groups A, B, and C) at end of study. Pain intensity significantly decreased from pretreatment [visual analog scale (VAS)=57% and numerical rating pain scale=5.9 points) until the end of the study (day 28: 34% and 3.8 points; n=55), without differences between age-groups (VAS day 28: A=34%; B=34%; C=33%). Two-third of patients (A=67%; B=67%; C=68%) completed the study at day 28; the rates and reasons for premature study termination were similar in all age-groups. Daily mean pain intensities (days 10 to 28) were even lower (P<0.005) in elderly patients (VAS A=35.8%) as compared with both younger age-groups (B=39.8%; C=39.9%). Sleep duration incidences above 6 hours improved from 34% to a plateau above 50% (A=68%; B=38%; C=57%) for patients terminating the study as planned. The need for rescue medication was lowest in elderly patients (A=107; B=136; C=253 mug/d, days 10 to 28). The opioid typical adverse event profile (predominantly dizziness and nausea) and local skin tolerability were both comparable for younger and elderly patients. CONCLUSIONS: This investigation showed that the treatment of chronic pain with transdermal buprenorphine in elderly patients above the age of 65 years is at least as effective, tolerable, and safe as in patients studied in 2 age-groups below that age.
Subject(s)
Analgesics, Opioid/administration & dosage , Buprenorphine/administration & dosage , Geriatrics , Pain/drug therapy , Administration, Cutaneous , Adult , Age Factors , Aged , Aged, 80 and over , Drug Evaluation , Female , Humans , Male , Middle Aged , Pain MeasurementABSTRACT
BACKGROUND: In 2001, a transdermal matrix patch formulation of buprenorphine was approved for the treatment of moderate to severe cancer pain and severe pain that is unresponsive to nonopioid analgesics. The primary recommendation contained in the prescribing information was that transdermal patches be worn for a 3-day period before application of a new patch. OBJECTIVE: This study was conducted to evaluate the potential for extending the time the buprenorphine patch is worn from 3 to 4 days. METHODS: This single-center, randomized, open-label, crossover Phase III study compared the efficacy and tolerability of the buprenorphine transdermal patch applied for different durations, with patch changes every 3 days versus every 4 days (12 days each), in patients with chronic moderate or severe pain of malignant or nonmalignant origin. Study participants were aged >18 years, had already responded to at least 4 weeks of transdermal buprenorphine, and had achieved steady-state conditions for at least 2 weeks before enrollment. The primary end point was patients' rating of the quality of treatment (analgesic efficacy and tolerability, rated on a 5-point scale: very good, good, satisfactory, poor, and inadequate) at the completion of each treatment regimen. Also recorded were physicians' ratings of the quality of treatment; pain intensity, rated on an 11-point numerical rating scale (from 0 = no pain to 10 = worst pain imaginable) and on the McGill Pain Questionnaire (MPQ) (maximum pain = 3.0); health status, assessed using the 36-item Short Form Health Survey (SF-36), expressed as a percentage of the best health condition (100%); and pain relief (5-point scale: complete, good, satisfactory, slight, and none). Local skin tolerability was evaluated for objective and subjective dermatologic symptoms at the patch application sites. Patients recorded daily pain intensities at specified times of day and night, pain relief (5-point verbal rating scale), and sleep duration (
Subject(s)
Analgesics, Opioid/administration & dosage , Buprenorphine/administration & dosage , Pain/etiology , Pain/prevention & control , Administration, Cutaneous , Aged , Analgesics, Opioid/adverse effects , Buprenorphine/adverse effects , Cross-Over Studies , Drug Administration Schedule , Erythema/chemically induced , Female , Humans , Male , Middle Aged , Pain Measurement , Patient Satisfaction , Quality of Health Care , Severity of Illness Index , Treatment OutcomeABSTRACT
BACKGROUND: Tramadol is widely prescribed, even to the eldest patients. Although age-related differences in pharmacologic responsiveness are to be expected, the pharmacodynamic and pharmacokinetic (PK) properties of tramadol have not been systematically compared between patients of various ages. OBJECTIVE: The aim of this study was to explore the effectiveness, PK properties, and safety profile of 2 galenic tramadol formulations in 3 similarly sized age groups with malignant and nonmalignant pain of moderate to severe intensity. METHODS: This prospective, age-group-controlled study was conducted at the ambulatory pain clinic of the Landeskrankenhaus Kärnten, Klagenfurt, Austria. Male and female adults with malignant and nonmalignant pain of moderate to severe intensity were eligible. Patients were stratified into similarly sized age groups, as follows: >or=75, 65-<75, and <65 years. Patients first received the immediate-release galenic formulation of tramadol (tramadol IR) until steady state was achieved, followed by the sustained-release formulation (tramadol SR) until steady state. Serum concentrations of tramadol and its active metabolite (O-desmethyl-tramadol [M1]) were measured using gas chromatography to estimate the age-related PK handling of the analgesic drug. Three validated scales were used to measure pain intensity during the study: a 100-mm visual analog scale (VAS), an 11-point numeric analog scale (NAS), and a 4-point verbal rating scale (VRS). Tolerability was assessed by evaluating daily answers about the potential occurrence of adverse events (and respective details such as type and severity) from baseline until the end of the observation period. RESULTS: A total of 100 patients were enrolled (58 women, 42 men; mean [SD] age, 65.2 [15.0] years; >or=75, 30 patients; 65-<75, 31 patients; and <65 years, 39 patients). Predominant causes of pain were neoplasms (27.4% of causes) and injury and other external causes (20.8%), and diseases of the musculoskeletal and connective-tissues systems (19.8%). Fifty-five patients completed the study and provided all data as planned. Mean (SEM) steady-state tramadol IR doses were 250 (20.2), 277 (39.8), and 325 (33.1) mg/d in patients aged >or=75, 65-<75, and 65 years, respectively (P = NS); tramadol SR, 278 (27.5), 306 (39.7), and 340 (35.1) mg/d (P = NS). Serum concentrations of tramadol and M1 were statistically similar across all 3 age groups. Overall, mean pain intensity scores, as measured using the VAS and NAS, were decreased from baseline (62.4 [2.0] mm and 6.22 [0.22] points, respectively) to steady state with tramadol IR (23.6 [2.9] mm and 2.65 [0.30] points) and tramadol SR (16.9 [2.5] mm and 1.91 [0.26] points) (all, P < 0.001). Pain intensity before and improvements during both treatment phases were similar across all 3 age groups. RESULTS: for pain intensity on the VRS also did not find age-related differences. The predominant adverse effects were nausea (27.0% of patients), dizziness and giddiness (18.0%), and malaise and fatigue (15.0%); no significant differences in adverse events were found between age groups. CONCLUSIONS: The fate of tramadol and its active metabolite, and their clinical effects, have been examined here for the first time in a prospective cohort study, which compared patients aged <65 years, 65-<75 years, and >or=75 years. In contrast to expectations, it was concluded that tramadol IR and tramadol SR were both generally well tolerated and effective in the treatment of moderate to severe pain in any of the 3 age groups in these patients. Although the eldest group of patients consumed, on average, 20% less tramadol (P = NS) than the youngest group, the PK properties of both drugs were not changed when given to elderly patients.