Buccal acetaminophen provides fast analgesia: two randomized clinical trials in healthy volunteers

N-acetylcysteine prevents glutathione decrease and does not interfere with paracetamol antinociceptive effect at therapeutic dosage: a randomized double-blind controlled trial in healthy subjects

Paracetamol (APAP) may lead to hepatic changes even at therapeutic dosages. Glutathione (GSH) plays a pivotal role in APAP metabolism as it allows the detoxification of a toxic metabolite. N-Acetylcysteine (NAC) is APAP antidote, is also largely used as a mucoactive drug and is often associated with APAP. This study aims at evaluating if 1- NAC modifies APAP pain efficacy and 2- NAC prevents glutathione depletion with APAP at therapeutic doses. This double-blind randomized controlled study (NCT02206178) was carried out in 24 healthy volunteers. APAP was given for 4 days (1 g ×4 daily) with NAC or with placebo. Thermal pain tests, whole blood GSH, and hepatic enzymes (ASAT, ALAT) were measured before (D0) and after (D4) oral APAP-NAC or APAP-placebo intake. anova for repeated measures adapted to cross-overdesign was performed and a two-tailed type I error was fixed at 5%. The primary endpoint was the area under the curve (0-240 min) of pain intensity (Numerical Scale) after thermal pain stimulation using Pathway-Medoc^® . APAP antinociceptive effect was similar in both groups. GSH was maintained to its baseline value in the APAP/NAC group but diminished in the APAP/placebo group (P = 0.033). This study shows for the first time that APAP antinociceptive effectiveness is not influenced by NAC. It also shows that the effect of APAP at therapeutic dosage on GSH may be counteracted by NAC. These issues are particularly important for patients as APAP is often prescribed for years as a first-line pain treatment and further trials in patients are now warranted.

Topic delivery of analgesics in oral surgery

Introduction: Following any oral surgery procedure, postoperative pain is an inevitable outcome and can be described as moderate to severe. The pain management is essential for the comfort and the well-being of the patients. Topical delivery and more specifically transmucosal delivery systems seem to be of great value for the development of new pain management strategies. Method: A systematic literature review was performed using PubMedCentral database. Only PubMedCentral indexed publications were selected and included if they described i) a human clinical study with pharmacokinetic and/or pain relief assessment a biomaterial for topic delivery, ii) the delivery of analgesics or NSAIDs for analgesic purpose and iii) a biomaterial for topic delivery. Results: Ten articles were selected among which 4 pharmacokinetic studies and 8 studies describing pain relief. Six of the selected articles were well defined with a good scientific level of evidence (level 2) and 4 of them with a low level of evidence. Discussion: The clinical investigations demonstrated a good analgesia, a rapid pain relief with a decrease of the administered doses compared to the oral administration. Moreover, these topic analgesics were well tolerated by the patients. Number of devices was developed for the topical delivery after oral surgery procedures. Excepting a gelatin sponge and a hydro alcoholic gel, most of the devices were made of cellulose and its derivatives. Authors reported that the materials showed a good maintenance at the site of application and the release of the analgesic was well controlled over the time. Conclusion: However, well conducted large clinical trials are still missing in order to validate the absence of side effects.

Rédiger un protocole douleur : quelle méthode atraumatique pour l’urgentiste ?

Les protocoles « antalgie » sont des outils incontournables pour tous les services d’urgence dans le cadre de l’amélioration de la prise en charge de la douleur. Suivre les recommandations d’experts ne peut suffire. Un protocole doit proposer des conduites à tenir ciblées sur des situations définies, validées scientifiquement, adaptées au contexte du service et au personnel concerné, dans un cadre réglementaire et légal précis. Mais l’élaboration d’un protocole peut s’avérer une expérience pénible pour l’urgentiste, même si c’est une des missions extracliniques essentielles à la professionnalisation du métier. Pour le non-algologue, sa conception et sa rédaction peuvent être perçues comme fastidieuses et non prioritaires, mais cette inertie retarde dangereusement la mise à jour de nos stratégies thérapeutiques globales, en particulier en traumatologie. L’optimisation de cette tâche et un gain de temps sont pourtant possibles grâce à un guide méthodologique, des modèles, des documents types, tous accessibles, mais parfois mal référencés : l’expert pourra ainsi consacrer son temps au contenu et à l’adhésion des équipes plutôt qu’à la forme et, in fine, au patient. Une « protocolisation » de l’élaboration de nos protocoles est sans doute le moyen de les réaliser et de les mettre à jour plus efficacement, plus vite et sans douleur. Se doter d’un protocole d’antalgie est en fait une opportunité pour les équipes davantage qu’une contrainte, à condition de proposer une méthodologie adaptée à la culture de la médecine d’urgence, transversale, accessible, priorisée.

Paracetamol in Older People: Towards Evidence-Based Dosing?

Paracetamol is the most commonly used analgesic in older people, and is mainly dosed according to empirical dosing guidelines. However, the pharmacokinetics and thereby the effects of paracetamol can be influenced by physiological changes occurring with ageing. To investigate the steps needed to reach more evidence-based paracetamol dosing regimens in older people, we applied the concepts used in the paediatric study decision tree. A search was performed to retrieve studies on paracetamol pharmacokinetics and safety in older people (> 60 years) or studies that performed a (sub) analysis of pharmacokinetics and/or safety in older people. Of 6088 articles identified, 259 articles were retained after title and abstract screening. Further abstract and full-text screening identified 27 studies, of which 20 described pharmacokinetics and seven safety. These studies revealed no changes in absorption with ageing. A decreased (3.9-22.9%) volume of distribution (Vd) in robust older subjects and a further decreased Vd (20.3%) in frail older compared with younger subjects was apparent. Like Vd, age and frailty decreased paracetamol clearance (29-45.7 and 37.5%) compared with younger subjects. Due to limited and heterogeneous evidence, it was difficult to draw firm and meaningful conclusions on changed risk for paracetamol safety in older people. This review is a first step towards bridging knowledge gaps to move to evidence-based paracetamol dosing in older subjects. Remaining knowledge gaps are safety when using therapeutic dosages, pharmacokinetics changes in frail older people, and to what extent changes in paracetamol pharmacokinetics should lead to a change in dosage in frail and robust older people.

Pain Management of Pediatric Musculoskeletal Injury in the Emergency Department: A Systematic Review

Background. Pain management for children with musculoskeletal injuries is suboptimal and, in the absence of clear evidence-based guidelines, varies significantly. Objective. To systematically review the most effective pain management for children presenting to the emergency department with musculoskeletal injuries. Methods. Electronic databases were searched systematically for randomized controlled trials of pharmacological and nonpharmacological interventions for children aged 0-18 years, with musculoskeletal injury, in the emergency department. The primary outcome was the risk ratio for successful reduction in pain scores. Results. Of 34 studies reviewed, 8 met inclusion criteria and provided data on 1169 children from 3 to 18 years old. Analgesics used greatly varied, making comparisons difficult. Only two studies compared the same analgesics with similar routes of administration. Two serious adverse events occurred without fatalities. All studies showed similar pain reduction between groups except one study that favoured ibuprofen when compared to acetaminophen. Conclusions. Due to heterogeneity of medications and routes of administration in the articles reviewed, an optimal analgesic cannot be recommended for all pain categories. Larger trials are required for further evaluation of analgesics, especially trials combining a nonopioid with an opioid agent or with a nonpharmacological intervention.

Acetaminophen: old drug, new issues

INTRODUCTION

The purpose of this review was to discuss new issues related to safety, labeling, dosing, and a better understanding of the analgesic effect of acetaminophen.

METHODS

The MEDLINE, Embase, Cochrane, and PubMed databases were searched. Additionally, the bibliography of all relevant articles and textbooks were manually searched. Two reviewers independently selected the relevant articles.

RESULTS

Concerns about acetaminophen overdose and related liver failure have led the US Food and Drug Administration to mandate new labeling on acetaminophen packaging. In addition, large-scale epidemiologic studies increasingly report evidence for second-generation adverse effects of acetaminophen. Prenatal exposure to acetaminophen is associated with neurodevelopmental and behavioral disorders. Recent studies also suggest that acetaminophen is a hormone disrupter (ie, it interferes with sex and thyroid hormone function essential for normal brain development) and thus may not be considered a safe drug during pregnancy. Finally, emerging evidence suggests that although the predominant mechanism by which acetaminophen exerts its therapeutic effect is by inhibition of cyclooxygenase, multiple other mechanisms also contribute to its analgesic effect.

CONCLUSIONS

Available evidence suggests that indiscriminate usage of this drug is not warranted. and its administration to a pregnant patient should be considered with great caution.