Tapentadol: Can It Kill Two Birds with One Stone without Breaking Windows?

Efficacy of high-voltage, long-duration pulsed radiofrequency for the treatment of acute herpes zoster-related trigeminal neuralgia in a patient with permanent pacemaker

Background

Recognizing the seriousness of the misuse and abuse of medical narcotics, the South Korean government introduced the world's first narcotic management system, the Narcotics Information Management System (NIMS). This study aimed to explore the recent one-year opioid prescribing patterns in South Korea using the NIMS database.

Methods

This study analyzed opioid prescription records in South Korea for the year 2022, utilizing the dispensing/administration dataset provided by NIMS. Public data from the Korean Statistical Information Service were also utilized to explore prescription trends over the past four years. The examination covered 16 different opioid analgesics, assessed by the total number of units prescribed based on routes of administration, type of institutions, and patients’ sex and age group. Additionally, the disposal rate for each ingredient was computed.

Results

In total, 206,941 records of 87,792,968 opioid analgesic units were analyzed. Recently, the overall quantity of prescribed opioid analgesic units has remained relatively stable. The most prescribed ingredient was oral oxycodone, followed by tapentadol and sublingual fentanyl. Tertiary hospitals had the highest number of dispensed units (49.4%), followed by community pharmacies (40.2%). The highest number of prescribed units was attributed to male patients in their 60s. The disposal rates of the oral and transdermal formulations were less than 0.1%.

Conclusions

Opioid prescription in South Korea features a high proportion of oral formulations, tertiary hospital administration, pharmacy dispensing, and elderly patients. Sustained education and surveillance of patients and healthcare providers is required.

Experience from a single-center study on multimodal medication therapy for patients with complex regional pain syndrome

BACKGROUND

Despite the application of various therapeutic methods, pain caused by complex regional pain syndrome (CRPS) is not sufficiently managed and often progresses to a chronic stage. For the systematic and effective treatment of CRPS, we developed an algorithm for multimodal medication therapy based on the established pathophysiology of CRPS to control CRPS-related pain.

OBJECTIVE

In this study, we present the outcomes of our novel algorithm for multimodal medication therapy for patients with CRPS, consisting of three major components: multimodal oral medication, intravenous ketamine, and intravenous lidocaine therapy.

METHODS

We retrospectively investigated patients with CRPS who received multimodal therapy. Pain severity scores were evaluated using a numerical rating scale at four time points (P1, pain at initial consultation; P2, pain after oral medication; P3, pain after ketamine treatment; and P4, pain after lidocaine treatment). The effect of the multimodal medication therapy algorithm on pain management was evaluated at each time point.

RESULTS

In patients with CRPS, multimodal oral medication, intravenous ketamine, and intravenous lidocaine therapies led to significantly improved pain control (p< 0.05). Additionally, the combination of these three therapies (through the multimodal medication therapy algorithm) resulted in significant pain relief in patients with CRPS (p< 0.05).

CONCLUSIONS

Our multimodal medication therapy algorithm effectively controlled pain in patients with CRPS. However, further prospective studies with large sample sizes and randomized controlled trials are needed for more accurate generalization.

Tramadol and Tapentadol Induce Conditioned Place Preference with a Differential Impact on Rewarding Memory and Incubation of Craving

Tramadol and tapentadol, synthetic opioids commonly prescribed for moderate-to-severe pain, have a unique pharmacology that optimizes their analgesia and safety. However, they are not devoid of risks, presenting addictive, abuse, and dependence potential. While tramadol-reinforcing properties have been documented by various studies with human and animal models, including conditioned place preference (CPP) assays, no similar studies have been performed with tapentadol. In the present study, we performed CPP assays by intraperitoneally administering Wistar rats with a tramadol/tapentadol therapeutic dose. Animal permanence and the number of entries in the CPP compartments were recorded in the preconditioning phase and then 1 (T1), 7 (T7), and 14 (T14) days after conditioning. Both opioids induced a change in place preference (T1), suggesting that they have short-term reinforcing properties. However, only tramadol was associated with place preference retention (T7 and T14), with an increase in the number of entries in the opioid-paired compartment (T1 and T7), showing that it causes rewarding memory and incubation of craving. The results indicate that at therapeutic doses: (1) both drugs cause short-term rewarding effects and (2) as opposed to tramadol, tapentadol does not cause CPP retention, despite its higher central nervous system activity and stricter scheduling.

Polypharmacology: The science of multi-targeting molecules

Polypharmacology is a concept where a molecule can interact with two or more targets simultaneously. It offers many advantages as compared to the conventional single-targeting molecules. A multi-targeting drug is much more efficacious due to its cumulative efficacy at all of its individual targets making it much more effective in complex and multifactorial diseases like cancer, where multiple proteins and pathways are involved in the onset and development of the disease. For a molecule to be polypharmacologic in nature, it needs to possess promiscuity which is the ability to interact with multiple targets; and at the same time avoid binding to antitargets which would otherwise result in off-target adverse effects. There are certain structural features and physicochemical properties which when present would help researchers to predict if the designed molecule would possess promiscuity or not. Promiscuity can also be identified via advanced state-of-the-art computational methods. In this review, we also elaborate on the methods by which one can intentionally incorporate promiscuity in their molecules and make them polypharmacologic. The polypharmacology paradigm of "one drug-multiple targets" has numerous applications especially in drug repurposing where an already established drug is redeveloped for a new indication. Though designing a polypharmacological drug is much more difficult than designing a single-targeting drug, with the current technologies and information regarding different diseases and chemical functional groups, it is plausible for researchers to intentionally design a polypharmacological drug and unlock its advantages.

Comparative study of dezocine, pentazocine and tapentadol on antinociception and physical dependence

AIMS

Dezocine and pentazocine, widely prescribed in China for postoperative pain, were initially considered as mixed agonist/antagonist targeting μ-opioid receptors (MORs) and κ-opioid receptors (KORs). However, dezocine has been revealed to alleviate chronic neuropathic pain through MOR activation and norepinephrine reuptake inhibition (NRI). This study investigated dezocine- and pentazocine-induced antinociception and physical dependence development, compared to the typical MOR-NRI opioid tapentadol.

MAIN METHODS

Calcium mobilization assay was conducted to assess the potency of the drugs while hot-plate test was performed to compare the antinociception. Physical dependence development was compared with morphine.

KEY FINDINGS

Treatment with dezocine, pentazocine and tapentadol stimulated calcium mobilization in HEK293 cells stably expressed MORs but not KORs, whereas dezocine and pentazocine inhibited KOR activities. Subcutaneously injected dezocine-, tapentadol- and pentazocine-induced antinociception dose-dependently, in hot-plate test. Intrathecally injected MOR antagonist CTAP, norepinephrine depletor 6-OHDA and α₂-adrenoceptor (α₂-AR) antagonist yohimbine partially antagonized dezocine, pentazocine and tapentadol antinociception. Whereas specific KOR antagonist GNTI did not alter their antinociception, the putative inverse KOR agonist nor-BNI reduced dezocine and pentazocine antinociception. Moreover, combined CTAP and 6-OHDA or yohimbine blocked dezocine and tapentadol antinociception but displayed the same partial inhibition on pentazocine antinociception as CTAP alone. Furthermore, compared to morphine and pentazocine, long-term treatment with dezocine and tapentadol produced much less physical dependence-related withdrawal signs, which were restored by spinal 6-OHDA or yohimbine treatment.

SIGNIFICANCE

Our findings illustrated that dezocine and tapentadol, but not pentazocine, exert remarkable antinociception in nociceptive pain with less abuse liability via dual mechanisms of MOR activation and NRI.

Tapentadol, the new kid on the block in India: Is it time to worry?

BACKGROUND AND OBJECTIVES

Large-scale prospective case series of tapentadol abuse or dependence in India is not available. Hence, we aimed to study the prevalence and profile of tapentadol users in a treatment-seeking population.

MATERIALS AND METHODS

The study had prospective and retrospective arms. We collected 8-month prospective data by face-to-face interviews (n = 70) and 8-year retrospective data from case notes (n = 26) with either tapentadol misuse/abuse or dependence in patients attending a de-addiction center.

RESULTS

The prevalence of tapentadol abuse or dependence was 25% among the pharmaceutical opioid users. Concurrent use of other opioids was seen in >80% of participants of both the arms. Major sources of tapentadol were chemists (without a prescription) (53%) and doctors (prescriptions) (40%). Patients in the tapentadol dependence group had a significantly higher dose, duration, and pharmaceutical opioid use.

CONCLUSION

India needs awareness promotion, training, availability restriction, and provision of treatment for tapentadol abuse or dependence.

Repeated Administration of Clinical Doses of Tramadol and Tapentadol Causes Hepato- and Nephrotoxic Effects in Wistar Rats

Tramadol and tapentadol are fully synthetic and extensively used analgesic opioids, presenting enhanced therapeutic and safety profiles as compared with their peers. However, reports of adverse reactions, intoxications and fatalities have been increasing. Information regarding the molecular, biochemical, and histological alterations underlying their toxicological potential is missing, particularly for tapentadol, owing to its more recent market authorization. Considering the paramount importance of liver and kidney for the metabolism and excretion of both opioids, these organs are especially susceptible to toxicological damage. In the present study, we aimed to characterize the putative hepatic and renal deleterious effects of repeated exposure to therapeutic doses of tramadol and tapentadol, using an in vivo animal model. Male Wistar rats were randomly divided into six experimental groups, composed of six animals each, which received daily single intraperitoneal injections of 10, 25 or 50 mg/kg tramadol or tapentadol (a low, standard analgesic dose, an intermediate dose and the maximum recommended daily dose, respectively). An additional control group was injected with normal saline. Following 14 consecutive days of administration, serum, urine and liver and kidney tissue samples were processed for biochemical, metabolic and histological analysis. Repeated administration of therapeutic doses of both opioids led to: (i) increased lipid and protein oxidation in liver and kidney, as well as to decreased total liver antioxidant capacity; (ii) decreased serum albumin, urea, butyrylcholinesterase and complement C3 and C4 levels, denoting liver synthesis impairment; (iii) elevated serum activity of liver enzymes, such as alanine aminotransferase, aspartate aminotransferase, alkaline phosphatase and γ-glutamyl transpeptidase, as well as lipid profile alterations, also reflecting hepatobiliary commitment; (iv) derangement of iron metabolism, as shown through increases in serum iron, ferritin, haptoglobin and heme oxygenase-1 levels. In turn, elevated serum cystatin C, decreased urine creatinine output and increased urine microalbumin levels were detected upon exposure to tapentadol only, while increased serum amylase and urine N-acetyl-β-D-glucosaminidase activities were observed for both opioids. Collectively, these results are compatible with kidney injury. Changes were also found in the expression levels of liver- and kidney-specific toxicity biomarker genes, upon exposure to tramadol and tapentadol, correlating well with alterations in lipid profile, iron metabolism and glomerular and tubular function. Histopathological analysis evidenced sinusoidal dilatation, microsteatosis, mononuclear cell infiltrates, glomerular and tubular disorganization, and increased Bowman's spaces. Although some findings are more pronounced upon tapentadol exposure, our study shows that, when compared with acute exposure, prolonged administration of both opioids smooths the differences between their toxicological effects, and that these occur at lower doses within the therapeutic range.

Sublingual delivery of chondroitin sulfate conjugated tapentadol loaded nanovesicles for the treatment of osteoarthritis

Recent treatment approaches of osteoarthritis (OA) face a number of obstacles due to the progressive multitude of pain generators, nociceptive mechanisms, first pass mechanism, less efficacy and compromised safety. The present study was aimed to bring a novel approach for the effective management of OA, by developing sublingual targeted nanovesicles (NVs) bearing tapentadol HCl (TAP), surface modified with chondroitin sulfate (CS). Optimized nontargeted nanovesicle formulation (MB-NV) was developed by an ultrasound method, characterized as spherical in shape, nanometric in size (around 150 nm) with narrow size distribution (polydispersity index <0.5), and good entrapment efficiency (around 50%). MB-NV conjugated with CS which was confirmed by IR and ¹H NMR spectroscopy. C-MB-NV showed improved pharmacokinetics parameters i.e. increased t_1/2 (9.7 h), AUC (159.725 μg/mL*h), and MRT (14.99 h) of TAP than nontargeted formulation and plain drug soln. C-MB-NV in in vitro release studies proved sustained drug release pattern for more than 24 h following Higuchi model kinetics with Fickian diffusion (n ≤ 0.5).Targeted nanovesicles exhibited an improved bioavailability and enhanced analgesic activity in a disease-induced Wistar rat model which indicated the superior targeting potential of C-MB-NV exploiting CD44 receptors as mediators, overexpressed at the affected joints in the OA model. It could be a propitious approach to accustomed therapies for methodical and efficient management in advanced OA therapy.

Tapentadol for neuropathic pain: a review of clinical studies

Neuropathic pain (NP) is an enormous burden for patients, caregivers and society. NP is a pain state that may develop after injury of the peripheral or central nervous system because of a wide range of diseases and traumas. A NP symptom component can be found also in several types of chronic pain. Many NP patients are substantially disabled for years. Due to its chronicity, severity and unpredictability, NP is difficult to treat. Tapentadol is a central-acting oral analgesic with combined opioid and noradrenergic properties, which make it potentially suitable for a wide range of pain conditions, particularly whenever a NP component is present or cannot be excluded. In randomized controlled trials, tapentadol has proved to be effective in relieving NP in diabetic peripheral neuropathy and in chronic low back pain. In observational studies, tapentadol reduced NP in chemotherapy-induced peripheral neuropathies, blood and solid cancers, and the NP component in neck pain and Parkinson's disease. This narrative review aims to provide clinicians with a broad overview of tapentadol effects on NP.

Opioid-induced constipation: a narrative review of therapeutic options in clinical management

Pain therapy often entails gastrointestinal adverse events. While opioids are effective drugs for pain relief, the incidence of opioid-induced constipation (OIC) varies greatly from 15% to as high as 81%. This can lead to a significant impairment in quality of life, often resulting in discontinuation of opioid therapy. In this regard, a good doctor-patient relationship is especially pivotal when initiating opioid therapy. In addition to a detailed history of bowel habits, patient education regarding the possible gastrointestinal side effects of the drugs is crucial. In addition, the bowel function must be regularly evaluated for the entire duration of treatment with opioids. Furthermore, if the patient has preexisting constipation that is well under control, continuation of that treatment is important. In the absence of such history, general recommendations should include sufficient fluid intake, physical activity, and regular intake of dietary fiber. In patients of OIC with ongoing opioid therapy, the necessity of opioid use should be critically reevaluated in terms of an with acceptable quality of life, particularly in cases of non-cancer pain. If opioids must be continued, lowering the dose may help, as well as changing the type of opioid. If these measures do not suffice, the next step for persistent OIC is the administration of laxatives. If these are ineffective as well, treatment with peripherally active μ-opioid receptor antagonists should be considered. Enemas and irrigation are emergency measures, often used as a last resort.

Comparative pharmacology and toxicology of tramadol and tapentadol

Moderate-to-severe pain represents a heavy burden in patients' quality of life, and ultimately in the society and in healthcare costs. The aim of this review was to summarize data on tramadol and tapentadol adverse effects, toxicity, potential advantages and limitations according to the context of clinical use. We compared data on the pharmacological and toxicological profiles of tramadol and tapentadol, after an extensive literature search in the US National Library of Medicine (PubMed). Tramadol is a prodrug that acts through noradrenaline and serotonin reuptake inhibition, with a weak opioid component added by its metabolite O-desmethyltramadol. Tapentadol does not require metabolic activation and acts mainly through noradrenaline reuptake inhibition and has a strong opioid activity. Such features confer tapentadol potential advantages, namely lower serotonergic, dependence and abuse potential, more linear pharmacokinetics, greater gastrointestinal tolerability and applicability in the treatment of chronic and neuropathic pain. Although more studies are needed to provide clear guidance on the opioid of choice, tapentadol shows some advantages, as it does not require CYP450 system activation and has minimal serotonergic effects. In addition, it leads to less side effects and lower abuse liability. However, in vivo and in vitro studies have shown that tramadol and tapentadol cause similar toxicological damage. In this context, it is important to underline that the choice of opioid should be individually balanced and a tailored decision, based on previous experience and on the patient's profile, type of pain and context of treatment.

SIGNIFICANCE

This review underlines the need for a careful prescription of tramadol and tapentadol. Although both are widely prescribed synthetic opioid analgesics, their toxic effects and potential dependence are not completely understood yet. In particular, concerning tapentadol, further research is needed to better assess its toxic effects.

Cardiac Arrest Following Drug Abuse with Intravenous Tapentadol: Case Report and Literature Review

BACKGROUND Tapentadol is a centrally acting opioid analgesic, with a dual mode of action, as a norepinephrine reuptake inhibitor and an agonist of the μ-opioid receptor (MOR). Tapentadol is used for the management of musculoskeletal pain, and neuropathic pain associated with diabetic peripheral neuropathy. CASE REPORT A 32-year-old woman attended hospital for evaluation of an intractable headache. Computed tomography and magnetic resonance imaging of the brain were negative. She was found unresponsive in the bathroom on the day following hospital admission, and despite resuscitative measures, the patient died following cardiac arrest. Autopsy toxicology revealed significantly elevated levels of tapentadol, and bedside evidence suggested that the patient had self-administered this medication intravenously before her death. CONCLUSIONS We report a rare adverse effect of tapentadol causing respiratory depression leading to cardiac arrest. Medical examiners and forensic toxicologists should be aware of the toxicity of this novel opiate drug.