Nonsteroidal anti-inflammatory drugs, traditional opioids, and tramadol: contrasting therapies for the treatment of chronic pain

The plausible mechanisms of tramadol for treatment of COVID-19

Currently, no single medication has been approved for the management of coronavirus disease-2019 (COVID-19) caused by the new severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Therefore, drug repositioningby investigating the use of existing drugs for management of COVID-19 patients is considered a desperate need. Tramadol is a commonly prescribed analgesic drug for treatment of moderate to severe pain with less potential for dependence and respiratory depression. Multiple evidence support that tramadol is a promising drug for treatment of COVID-19 patients. Herein, we discuss the possible beneficial effects of using tramadol against SARS-CoV-2 infection and their underlying mechanism of action. The anti-inflammatory effect of tramadol may help to suppress the COVID-19 related cytokine storm through decreasing interleukin (IL)-6, tumor necrosis factor-alpha (TNF-α), and C-reactive protein (CRP). Besides, tramadol activates natural killer (NK) and T-cells and enhances IL-2 secretion, which produce immune-enhancing effect against SARS-CoV-2. Recent studies confirmed that COVID-19 patients with acute respiratory failure showed increased fibrin formation and polymerization that may lead to thrombosis. Tramadol owing to its hypocoagulable effect may protect against venous thromboembolism in these patients. Moreover, tramadol can exert a cardioprotective effect via decreasing lactate dehydrogenase (LDH) level which is elevated in most of patients with COVID-19. Furthermore, the severity and mortality of COVID-19 have been correlated with old age patients, which may be due to the lack of antioxidant mechanisms and increased oxidative damage. Tramadol could protect COVID-19 patient from disease complications by increases the antioxidant enzymes superoxide dismutase and glutathione peroxidase while diminished malondialdehyde. More interestingly, tramadol as an effective analgesic and antitussive may have a beneficial effect on COVID-19 patients suffering from cough, headache, ache, and pain. The tramadol anti-psychotic effect may also protect against psychiatric disorders associated with SARS-CoV-2 infection. Moreover, tramadol has bactericidal activity against a wide range of pathogens including Pseudomonas aeruginosa which is common in severe COVID-19 patients leading to pneumonia with worse clinical outcomes. Therefore, we hypothesize that tramadol might be a promising adjuvant therapeutic option against SARS-CoV-2 infection. Based on that, tramadol should be considered as adjuvant therapy for COVID-19 clinical trials.

Oral Coadministration of Fluconazole with Tramadol Markedly Increases Plasma and Urine Concentrations of Tramadol and the O-Desmethyltramadol Metabolite in Healthy Dogs

Tramadol is used frequently in the management of mild to moderate pain conditions in dogs. This use is controversial because multiple reports in treated dogs demonstrate very low plasma concentrations of O-desmethyltramadol (M1), the active metabolite. The objective of this study was to identify a drug that could be coadministered with tramadol to increase plasma M1 concentrations, thereby enhancing analgesic efficacy. In vitro studies were initially conducted to identify a compound that inhibited tramadol metabolism to N-desmethyltramadol (M2) and M1 metabolism to N,O-didesmethyltramadol (M5) without reducing tramadol metabolism to M1. A randomized crossover drug-drug interaction study was then conducted by administering this inhibitor or placebo with tramadol to 12 dogs. Blood and urine samples were collected to measure tramadol, tramadol metabolites, and inhibitor concentrations. After screening 86 compounds, fluconazole was the only drug found to inhibit M2 and M5 formation potently without reducing M1 formation. Four hours after tramadol administration to fluconazole-treated dogs, there were marked statistically significant (P < 0.001; Wilcoxon signed-rank test) increases in plasma tramadol (31-fold higher) and M1 (39-fold higher) concentrations when compared with placebo-treated dogs. Conversely, plasma M2 and M5 concentrations were significantly lower (11-fold and 3-fold, respectively; P < 0.01) in fluconazole-treated dogs. Metabolite concentrations in urine followed a similar pattern. This is the first study to demonstrate a potentially beneficial drug-drug interaction in dogs through enhancing plasma tramadol and M1 concentrations. Future studies are needed to determine whether adding fluconazole can enhance the analgesic efficacy of tramadol in healthy dogs and clinical patients experiencing pain.

Who is Overdosing? An Updated Picture of Overdose Deaths From 2008 to 2015

PURPOSE

To determine the role of opioids in drug overdose deaths in Allen County, Indiana between January 1, 2008, and December 31, 2015.

METHODS

File review of 418 overdose deaths was performed using Indiana State Department of Health death certificates available through the Allen County Coroner's Office. Data from autopsy and toxicology reports and coroner-requested prescribing data from Indiana's Prescription Monitoring Program were reviewed. Cause of death and available data were analyzed to identify patterns and trends related to overdose deaths.

RESULTS

Four hundred eighteen drug overdose deaths were identified (336 accidental, 66 intentional, and 16 undetermined). Mean age was 42.5 years, 88.5% were Caucasian, and 68.7% were employed. The majority of deaths occurred at a place of residence (71.4%) and with other people present (57.5% of the time). Depression was the most common comorbidity identified. The most common drug classes identified by toxicology were opioids, followed by benzodiazepines. Significant increases in both heroin (35% of deaths in 2015 versus 8.2% in 2013) and fentanyl (30% of deaths in 2015 versus 2.2% in 2011) were observed.

CONCLUSIONS

Drug overdose continues to be a significant cause of death in Allen County. The majority of deaths were accidental and in relatively young, employed individuals. Prevention and awareness strategies should be encouraged, given that the majority of overdose deaths occurred at a place of residence with other people frequently present. Additional concerns about patterns of drug use were confirmed with marked increases in both heroin and fentanyl contributing to overdose deaths in the latter part of the study.

Efficacy and Safety Assessment of a Novel Once-Daily Tablet Formulation of Tramadol : A Randomised, Controlled Study versus Twice-Daily Tramadol in Patients with Osteoarthritis of the Knee

OBJECTIVE

To compare the 24-hour sustained efficacy and safety of a new tramadol once-daily formulation (tramadol OAD) using Contramid((R)) controlled-release technology with a marketed twice-daily formulation (tramadol BID). PATIENTS, DESIGN AND SETTING: 431 patients with osteoarthritis of the knee were enrolled in this randomised, double-blind, multicentre, parallel study. After titration to optimum dose (range 100-400mg), patients received medication for 12 weeks.

MAIN OUTCOME MEASURES AND RESULTS

Efficacy evaluations included: Western Ontario and McMaster University Osteoarthritis Index (WOMAC) scores (pain, stiffness, physical function and global), daily efficacy ratings (post-dose: tramadol OAD 24 hours; tramadol BID 12 hours), pain ratings over 24 hours, and patient and investigator overall ratings. Non-inferiority was demonstrated for the primary endpoint, mean percentage change in WOMAC pain score from baseline to week 12 (tramadol OAD 58%; tramadol BID 59%) [95% CI -7.67, 3.82]. The median optimum dose received was 200mg (both treatments). In 73% of patients, pain was mild to absent at the end of the dosing interval for both treatments (tramadol OAD 24 hours; tramadol BID 12 hours). Pain ratings over 24 hours were similar between groups, indicating 24-hour sustained efficacy for tramadol OAD. More tramadol BID patients reported dizziness/vertigo (37% vs 26%), vomiting (14% vs 8%) and headache (18% vs 13%) while tramadol OAD patients reported more somnolence (30% vs 21%).

CONCLUSIONS

This study demonstrated that this novel tramadol OAD formulation provides sustained analgesic efficacy over the entire 24-hour dosing interval and a clinically favourable safety profile, both of which will provide a clear clinical benefit.

Bridging health technology assessment (HTA) with multicriteria decision analyses (MCDA): field testing of the EVIDEM framework for coverage decisions by a public payer in Canada

BACKGROUND

Consistent healthcare decision making requires systematic consideration of decision criteria and evidence available to inform them. This can be tackled by combining multicriteria decision analysis (MCDA) and Health Technology Assessment (HTA). The objective of this study was to field-test a decision support framework (EVIDEM), explore its utility to a drug advisory committee and test its reliability over time.

METHODS

Tramadol for chronic non-cancer pain was selected by the health plan as a case study relevant to their context. Based on extensive literature review, a by-criterion HTA report was developed to provide synthesized evidence for each criterion of the framework (14 criteria for the MCDA Core Model and 6 qualitative criteria for the Contextual Tool). During workshop sessions, committee members tested the framework in three steps by assigning: 1) weights to each criterion of the MCDA Core Model representing individual perspective; 2) scores for tramadol for each criterion of the MCDA Core Model using synthesized data; and 3) qualitative impacts of criteria of the Contextual Tool on the appraisal. Utility and reliability of the approach were explored through discussion, survey and test-retest. Agreement between test and retest data was analyzed by calculating intra-rater correlation coefficients (ICCs) for weights, scores and MCDA value estimates.

RESULTS

The framework was found useful by the drug advisory committee in supporting systematic consideration of a broad range of criteria to promote a consistent approach to appraising healthcare interventions. Directly integrated in the framework as a "by-criterion" HTA report, synthesized evidence for each criterion facilitated its consideration, although this was sometimes limited by lack of relevant data. Test-retest analysis showed fair to good consistency of weights, scores and MCDA value estimates at the individual level (ICC ranging from 0.676 to 0.698), thus lending some support for the reliability of the approach. Overall, committee members endorsed the inclusion of most framework criteria and revealed important areas of discussion, clarification and adaptation of the framework to the needs of the committee.

CONCLUSIONS

By promoting systematic consideration of all decision criteria and the underlying evidence, the framework allows a consistent approach to appraising healthcare interventions. Further testing and validation are needed to advance MCDA approaches in healthcare decisionmaking.

Pain prevalence, experiences, and self-care management strategies among the community-dwelling elderly in Taiwan

The purpose of this study was to explore pain prevalence, experiences, and self-care management strategies among community-dwelling elderly in Taiwan. A convenience sample of elderly persons (n=1054) was recruited from outpatient clinics of two hospitals in northern Taiwan. Participants' pain prevalence was 50.0%, and the average number of pain sites was 3.9 (standard deviation [SD]=5.8). Knees were the most commonly described pain site, but the most painful site was the spinal cord area. The mean pain intensity was 3.1 (SD=1.8) and pain interference was 2.8 (SD=2.1). Most participants took prescribed medications to deal with pain; doctors were the main information source for this self-care strategy. Although participants reported using various self-care pain management strategies, most still reported moderate-to-severe worst pain. Moreover, our participants identified far fewer self-care strategies than U.S. elders with chronic pain. These findings suggest that community-dwelling elders in Taiwan know little about managing pain symptoms or ascribe a different meaning to pain than their U.S. counterparts. Because health care providers play an important role in helping the elderly to manage pain, the authors recommend training health care providers about Taiwanese elders' perceptions of pain, to perform regular pain assessments, and provide current knowledge about pain assessment and pain management strategies.

Self-management strategies to reduce pain and improve function among older adults in community settings: a review of the evidence

CONTEXT

Self-management strategies for pain hold substantial promise as a means of reducing pain and improving function among older adults with chronic pain, but their use in this age group has not been well defined.

OBJECTIVE

To review the evidence regarding self-management interventions for pain due to musculoskeletal disorders among older adults.

DESIGN

We searched the Medline and Cumulative Index to Nursing and Allied Health Literature databases to identify relevant articles for review and analyzed English-language articles that presented outcome data on pain, function, and/or other relevant endpoints and evaluated programs/strategies that could be feasibly implemented in the community. Abstracted information included study sample characteristics, estimates of treatment effect, and other relevant outcomes when present.

RESULTS

Retained articles (N = 27) included those that evaluated programs sponsored by the Arthritis Foundation and other programs/strategies including yoga, massage therapy, Tai Chi, and music therapy. Positive outcomes were found in 96% of the studies. Proportionate change in pain scores ranged from an increase of 18% to a reduction of 85% (median = 23% reduction), whereas change in disability scores ranged from an increase of 2% to a reduction of 70% (median = 19% reduction). Generalizability issues identified included limited enrollment of ethnic minority elders, as well as non-ethnic elders aged 80 and above.

CONCLUSIONS

Our results suggest that a broad range of self-management programs may provide benefits for older adults with chronic pain. Research is needed to establish the efficacy of the programs in diverse age and ethnic groups of older adults and identify strategies that maximize program reach, retention, and methods to ensure continued use of the strategies over time.

Single-Dose Intravenous Tramadol for Acute Migraine Pain in Adults: A Single-Blind, Prospective, Randomized, Placebo-Controlled Clinical Trial

BACKGROUND

Tramadol, an atypical opioid, is a narcotic analgesic used for pain management. A search of the current literature found no studies examining the efficacy of intravenous tramadol on migraine pain.

OBJECTIVE

The aim of this study was to investigate the efficacy and tolerability of a single dose of intravenous tramadol hydrogen chloride 100 mg in comparison with placebo in patients presenting with migraine.

METHODS

Adult migraineurs admitted consecutively to the emergency department of the Kocaeli University Hospital were enrolled in this single-blind (patients), prospective, randomized, placebo-controlled clinical trial. Patients were randomized to receive a 30-minute infusion of either intravenous tramadol (n = 17; 100 mg in 100-mL saline) or placebo (n = 17; 100-mL saline). Pain response was defined as a decrease of visual analogue scale (VAS) (0-100 mm) score to <50% of the pretreatment (baseline) value and a decrease of 4-point verbal scale (FPVS) score (0 = none, 1 = mild, 2 = moderate, 3 = severe) to mild or none. Pain-free response was defined as a decrease of both VAS and FPVS scores to 0. Pain was assessed at baseline and at 30 minutes and 1 hour after treatment completion. Migraine symptoms (eg, photophobia, phonophobia, nausea, vomiting) and adverse events (AEs) were assessed at the same time. A follow-up was also conducted by phone 24 hours after treatment.

RESULTS

Forty-four migraineurs were screened and 34 (28 women and 6 men; mean [SD] age, 39.5 [10.4] years; all were white) were enrolled in the study. Each group contained 11 patients with severe pain and 6 patients with moderate pain at baseline FPVS. At the end of 1 hour, pain response was reported by significantly more patients in the tramadol group than in the placebo group (12 [70.6%] vs 6 [35.3%]; P = 0.040). Pain-free response was reported by 5 (29.4%) patients in the tramadol group and 2 (11.8%) patients in the placebo group, although the difference was not statistically significant. Symptoms associated with migraine were also relieved in all patients reporting pain response. No AEs were observed. However, at the 24-hour follow-up, 1 patient in the tramadol group reported transient blurred vision and dizziness within the day of infusion. Headache recurrence was reported by 2 (16.7%) of the 12 patients with pain response in the tramadol group and 1 (16.7%) of 6 patients with pain response in the placebo group.

CONCLUSIONS

Intravenous tramadol appeared to be more effective than placebo in pain response rate at the end of the first hour. The slow infusion of tramadol 100 mg in 100-mL saline solution was well tolerated in this group of adult migraineurs.

Post-herpetic neuralgia in older adults: evidence-based approaches to clinical management

Many individuals across the globe have been exposed to the varicella-zoster virus (VZV) that causes chickenpox. After chickenpox has resolved, the virus remains latent in the dorsal root ganglia where it can re-emerge later in life as herpes zoster, otherwise known as shingles. Herpes zoster is a transient disease characterised by a dermatomal rash that is usually associated with significant pain. Post-herpetic neuralgia (PHN) is the term used for the condition that exists if the pain persists after the rash has resolved. Advanced age and compromised cell-mediated immunity are significant risk factors for reactivation of herpes zoster and the subsequent development of PHN. Though the pathophysiology of PHN is unclear, studies suggest peripheral and central demyelination as well as neuronal destruction are involved. Both the vaccine against VZV (Varivax) and the newly released vaccine against herpes zoster (Zostavax) may lead to substantial reductions in morbidity from herpes zoster and PHN. In addition, current evidence suggests that multiple medications are effective in reducing the pain associated with PHN. These include tricyclic antidepressants, antiepileptics, opioids, NMDA receptor antagonists as well as topical lidocaine (lignocaine) and capsaicin. Reasonable evidence supports the use of intrathecal corticosteroids, but the potential for neurological sequelae should prompt caution with their application. Epidural corticosteroids have not been shown to provide effective analgesia for PHN. Sympathetic blockade may assist in treating the pain of herpes zoster or PHN. For intractable PHN pain, practitioners have performed delicate surgeries and attempted novel therapies. Although such therapies may help reduce pain, they have been associated with disappointing results, with up to 50% of patients failing to receive acceptable pain relief. Hence, it is likely that the most effective future treatment for this disease will focus on prevention of VZV infection and immunisation against herpes zoster infection with a novel vaccine.

Pharmacokinetic and pharmacodynamic properties of tramadol IR and SR in elderly patients: a prospective, age-group-controlled study

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.

Pharmacokinetics and dose proportionality of three Tramadol Contramid® OAD tablet strengths

A three-way crossover study in 27 human volunteers was conducted to characterize the pharmacokinetics and to assess the dose proportionality of 100 mg, 200 mg and 300 mg strengths of a novel once-a-day tramadol controlled-release tablet (Tramadol Contramid OAD) following single-dose administration. Serial blood samples were collected at predefined timepoints over a 48 h period and racemic tramadol and O-desmethyltramadol concentrations in plasma were determined using a validated LC-MS/MS method. Pharmacokinetic parameters were derived using noncompartmental methods. Following dose normalization and logarithmic transformation of concentration-dependent parameters, the results were compared using analysis of variance (ANOVA). The residual variability thereby obtained was used to construct 90% classical confidence intervals. The two one-sided tests procedure was used for all pairwise comparisons. Dose proportionality was concluded since the 90% CI for the ratio of geometric means was included in the acceptance range of 0.80-1.25 for all comparisons.

Postoperative pain management in obstetric anesthesia–new challenges and solutions

The current understanding of pain processing mechanisms, the different pharmacologic drugs, and other nonpharmacologic means that can be used to manage postobstetric operation pain are reviewed.

Acetaminophen Overuse in the Ohio Medicaid Population

OBJECTIVE

To examine patterns of use of acetaminophen in patients with and without risk factors for hepatotoxicity in the Ohio Medicaid population.

DESIGN

Retrospective, cross-sectional analysis of claims data.

SETTING

Ohio.

PATIENTS

Ohio Medicaid patients (n = 22,496) who received at least 6 prescriptions for acetaminophen from November 1998 through April 1999.

MAIN OUTCOME MEASURE

Overuse of acetaminophen, defined as an average daily dose (ADD) greater than or equal to 4 grams/day or an ADD of greater than or equal to 3 grams/day along with diagnosis codes suggesting underlying liver dysfunction.

RESULTS

We identified 687 patients (3.05%) who received either greater than or equal to 4 grams/day or greater than or equal to 3 grams/day and had diagnosis codes suggesting underlying liver dysfunction (n = 128).

CONCLUSION

Although the number is relatively small, some Ohio Medicaid patients are receiving acetaminophen doses that exceed safety recommendations. Because acetaminophen overuse is the leading cause of liver failure, health care professionals should be alert to the possibility of acetaminophen overuse.

Cognitive-behavioral therapy for chronic low back pain in older persons: a preliminary study

OBJECTIVE

To determine the feasibility and potential efficacy of providing cognitive-behavioral therapy (CBT) to older persons with chronic low back pain (CLBP).

METHODS

This was an uncontrolled pilot study conducted at a senior housing center (SHC) in New Haven, Connecticut. Fourteen SHC residents aged 65 years and older who were cognitively intact (Mini Mental State Examination score > or =24) and had CLBP were recruited for the study. CBT was administered in 10 weekly individual sessions. Participants were phoned 5 days on average after each session (range: 3-7 days) to determine their comprehension and perceived usefulness of the CBT materials and adherence with the assigned homework exercises. Using standardized measures, we determined participants' levels of pain intensity, pain-related disability, and physical and social activity at baseline, and at 2 and 24 weeks posttreatment.

RESULTS

Participants had a mean age of 77.4 (+/-7.9 SD) years and were mostly female (86%). Thirteen (93%) participants completed all 10 sessions. Comprehension of CBT, defined as self-reported understanding of the materials presented each week, exceeded 97%. The perceived usefulness of each treatment session was assessed on a 0-10 scale, and the mean ratings for the sessions ranged from 7.5-9.4. The mean number of days that participants practiced the homework exercises each week varied from 1.8 to 4.0. Significant reductions (P < 0.01) in participants' pain intensity and pain-related disability scores were found at the 2-week posttreatment (vs pretreatment) assessment. These treatment effects waned over time, but did not return to pretreatment levels at 24 weeks. Participants' physical and social activity levels did not change.

CONCLUSIONS

CBT is a feasible treatment for cognitively intact, older persons with CLBP, and may be efficacious as well.

Pharmacology of oral combination analgesics: rational therapy for pain

No single analgesic agent is perfect and no single analgesic can treat all types of pain. Yet each agent has distinct advantages and disadvantages compared to the others. Hence, clinical outcomes might be improved under certain conditions with the use of a combination of analgesics, rather than reliance on a single agent. A combination is most effective when the individual agents act through different analgesic mechanisms and act synergistically. By activating multiple pain-inhibitory pathways, combination analgesics can provide more effective pain relief for a broader spectrum of pain, and might also reduce adverse drug reactions. This overview highlights the therapeutic potential of combining analgesic medications with different mechanisms of action, particularly a nonsteroidal anti-inflammatory drug (NSAID) or acetaminophen with an opioid or tramadol.

Pain management in dental practice: tramadol vs. codeine combinations

BACKGROUND

Tramadol hydrochloride is a novel, centrally acting analgesic with two complementary mechanisms of action: opioid and aminergic. First marketed in 1994, tramadol is frequently prescribed by physicians for the management of moderate-to-moderately severe chronic pain. The author evaluates its unique analgesic pharmacology and limited clinical utility for managing acute pain in dentistry.

TYPES OF STUDIES REVIEWED

Clinical drug trials in medicine and dentistry were reviewed to assess analgesic efficacy. Postmarketing surveillance studies and reports of adverse drug events were evaluated to determine short- and long-term safety.

RESULTS

Tramadol's maximum analgesic efficacy for relieving acute pain after oral surgery appears to be similar to that of 60 milligrams of codeine alone but less than that of a full therapeutic dose of a nonsteroidal anti-inflammatory drug or a codeine combination, such as aspirin/codeine or acetaminophen/codeine. Adverse events reported by patients receiving tramadol therapy since it was approved by the Food and Drug Administration suggest a risk of seizures, drug abuse and anaphylactoid reactions.

CLINICAL IMPLICATIONS

Tramadol has limited indication for management of acute pain in dentistry, possibly as an alternative analgesic when gastrointestinal side effects contraindicate the use of nonsteroidal anti-inflammatory drugs and when codeine/acetaminophen combination analgesics are not well-tolerated or are contraindicated.

Emerging concepts in the neurobiology of chronic pain: evidence of abnormal sensory processing in fibromyalgia

Chronic pain often differs from acute pain. The correlation between tissue pathology and the perceived severity of the chronic pain experience is poor or even absent. Furthermore, the sharp spatial localization of acute pain is not a feature of chronic pain; chronic pain is more diffuse and often spreads to areas beyond the original site. Of importance, chronic pain seldom responds to the therapeutic measures that are successful in treating acute pain. Physicians who are unaware of these differences may label the patient with chronic pain as being neurotic or even a malingerer. During the past decade, an exponential growth has occurred in the scientific underpinnings of chronic pain states. In particular, the concept of nonnociceptive pain has been refined at a physiologic, structural, and molecular level. This review focuses on this new body of knowledge, with particular reference to the chronic pain state termed "fibromyalgia."

Analgesic agents for the postoperative period. Nonopioids

For many reasons, nonopioid analgesics have proven to be of immense benefit in postoperative pain relief. Consideration of the limitations and side effects of opioids confirms the need for alternative, complementary analgesics. The current understanding of pain pathophysiology recognizes that many tissue and neuronal factors and changes are invoked by tissue damage, producing peripheral and central sensitization, and some of these may be modulated by the use of NSAIDs, NMDA antagonists, and local anesthetic agents. If successful preemptive analgesic techniques are developed, they will likely include the use of NSAIDs and perhaps NMDA antagonists. Nonopioids are of benefit in multimodal analgesia and allow acute rehabilitation of surgical patients. Acetaminophen, NSAIDs, alpha 2-antagonists, and NMDA antagonists are in routine use as components of multimodal analgesia, in combination with opioids or local anesthetic techniques. Tramadol is interesting because it has nonopioid and opioid actions that can be attributed to the two isomers found in the racemic mixture. Spinal neostigmine and the use of adenosine represent completely different mechanisms of nonopioid analgesia being investigated. Nonopioids, including lidocaine, ketamine, the anticonvulsants, and the antidepressants, are necessary for the treatment of patients with the difficult clinical problem of neuropathic pain that can present in the postoperative period.