Adverse effects of metamizole on heart, lung, liver, kidney, and stomach in rats.

BACKGROUND: Metamizole is banned in some countries because of its toxicity, although it is widely used in some European countries. In addition, there is limited information on its safety profile, and it is still debated whether it is toxic to the heart, lungs, liver, kidneys, and stomach. AIMS: Our study investigated the effects of metamizole on the heart, lung, liver, kidney, and stomach tissues of rats. METHODS: Eighteen rats were divided into three groups, wassix healthy (HG), 500 mg/kg metamizole (MT-500), and 1000 mg/kg metamizole (MT-1000). Metamizole was administered orally twice daily for 14 days. Meanwhile, the HG group received pure water orally. Biochemical, histopathologic, and macroscopic examinations were performed on blood samples and tissues. RESULTS: Malondialdehyde (MDA), total glutathione (tGSH), superoxide dismutase (SOD), and catalase (CAT) in the lung and gastric tissues of MT-500 and MT-1000 groups were almost the same as those of the HG (p > 0.05). However, MDA levels in the heart and liver tissues of MT-500 and MT-1000 groups were higher (p < 0.05) compared to the HG, while tGSH levels and SOD, and CAT activities were lower (p < 0.05). MDA levels of MT-500 and MT-1000 groups in the kidney tissue increased the most (p < 0.001), and tGSH levels and SOD and CAT activities decreased the most (p < 0.001) compared to HG. Metamizole did not cause oxidative damage in the lung and gastric tissue. While metamizole did not change troponin levels, it significantly increased alanine aminotransferase (ALT), aspartate aminotransferase (AST), blood urea nitrogen (BUN), and creatinine levels compared to HG. Histopathologically, mild damage was detected in heart tissue, moderate damage in liver tissue, and severe damage in renal tissue. However, no histopathologic damage was found in any groups' lung and gastric tissues. CONCLUSION: Metamizole should be used under strict control in patients with cardiac and liver diseases and it would be more appropriate not to use it in patients with renal disease.

The embryotoxic and teratogenic effects of metamizole sodium.

Drug use during pregnancy is an important issue that must be investigated due to its adverse effects on maternal and foetal health. This study aimed to determine the embryotoxic and teratogenic effects of in-ovo administered metamizole (dipyrone), which can be used when needed during pregnancy and has potent analgesic, antipyretic, anti-inflammatory, and long bone (tibia and femur) effects. This study used 240 fertile eggs from Atak S breed chickens, divided into eight equal groups: control, vehicle control, and 15.62, 31.25, 62.5, 125, 250 and 500 mg/kg metamizole. The eggs were hatched on the 21st day of incubation, and the chicks' body weights and mortality rates were determined. The right and left femur and tibia bones were resected from the chicks. Anatomical reference points were determined after removing the soft tissues of the bones, and necessary morphometric measures were taken from these points with a 0.01 mm precision using digital callipers. The 100% lethal dose (LD100) was identified in the highest examined dose (500 mg/kg) in the Chicken Embryotoxicity Screening Test (CHEST)-I stage. The CHEST-II stage determined the 50% lethal dose (LD50). High-dose metamizole affected skeletal development, significantly decreasing tibia and femur lengths and corpus thicknesses and increasing mortality.

Real-time and video-recorded pain assessment in beef cattle: clinical application and reliability in young, adult bulls undergoing surgical castration.

Bovine pain assessment relies on validated behavioral scales related to normal and pain-related behaviors. This study investigated the reliability and applicability of real-time and video-recorded pain assessment, and their agreement, in young, adult bulls undergoing surgical castration. Ten Nelore and nine Angus bulls underwent general anesthesia and surgical castration. Three-minute real-time observations and simultaneous videos were recorded at - 48 h (M0), before sedation, under fasting (M1), after surgery, 3 h after sternal recumbency (M2), after rescue analgesia (M3) and at 24 h (M4). Animals received morphine (after M2), dipyrone (after M3), and flunixin meglumine after surgical castration (M4). Two trained evaluators assessed real-time (n = 95) and video-recorded time-points (n = 95) using the Unesp-Botucatu Cattle Pain Scale (UCAPS). Both assessment methods inferred 'very good' reliability (≥ 0.81) with minimal bias, however, video-recorded assessment (4.33 ± 2.84) demonstrated slightly higher scores compared to real-time (3.08 ± 2.84). The results from this study suggest that UCAPS can be used in real-time or video-recorded to assess pain and guide analgesic therapy in cattle.

[New manifestation of a type 2-inflammation in the upper respiratory tract with nasal polyposis under treatment with an asthma biologic]. / Neumanifestation einer Typ-2-Inflammation im Bereich der oberen Atemwege mit Polyposis nasi unter einem Asthmabiologikum.

INTRODUCTION: For 7 years we gained experience of how asthma and chronic rhinosinusitis with nasal polyposis respond to biologics. In contrast, it is much less known, how ASA/NSAID intolerance (Widal's disease) behaves under biologicals. We therefore describe the case of a patient with both clinical conditions who reacted with a severe intolerance reaction under perioperative metamizole administration.

Prospective evaluation of the emetogenic profile and analgesic efficacy of intravenous ibuprofen and metamizole in the immediate postoperative period of pediatric acute appendicitis. / Evaluación prospectiva del perfil emético y la eficacia analgésica del ibuprofeno y el metamizol intravenosos en el postoperatorio inmediato de la apendicitis aguda pediátrica.

BACKGROUND: Literature comparing different alternatives for pain control in the immediate postoperative period of pediatric acute appendicitis (PAA) is scarce. MATERIALS AND METHODS: We prospectively compared the analgesic and emetogenic profile of intravenous ibuprofen and metamizole in the immediate postoperative period of PAA. For this purpose, we used a sample of patients operated on in 2021 in our center. Participants were recruited on arrival at the Emergency Department and histopathological confirmation of the diagnosis was obtained in all of them. Pain was evaluated every 8 hours after the surgery with validated visual analog scales ranging from 0 to 10 points. Repeated measures ANOVA was used to compare the evolution of pain in the 48 hours after surgery between the two groups. RESULTS: The sample included 95 patients (65% males) with a mean age of 9.7 years (sd: 3.14). 41 patients were treated with Ibuprofen (group 1) and 54 with metamizole (group 2). No significant differences were found in the level of pain either in the comparisons of point measurements or in its evolution in the 48 hours after surgery (p= 0.58). After adjusting for the received fluid therapy, children in the metamizole group had significantly more emetic episodes and needed significantly more doses of ondansetron. CONCLUSIONS: In our cohort, ibuprofen had a similar analgesic efficacy and a better emetogenic profile than metamizole in the immediate postoperative period of PAA. Future prospective, adequately controlled studies with larger sample sizes are needed to validate these findings.

INTRODUCCION: En la literatura existen pocas referencias que comparen las distintas alternativas disponibles para controlar el dolor en el postoperatorio inmediato de la apendicitis aguda pediátrica (AAP). MATERIAL Y METODOS: Comparación prospectiva del perfil analgésico y emético del ibuprofeno y el metamizol intravenosos en el postoperatorio inmediato de la AAP, para lo cual se recurre a una muestra de pacientes operados en 2021 en nuestro centro. Los participantes fueron reclutados a su llegada a Urgencias, obteniéndose confirmación histopatológica del diagnóstico en todos ellos. La evaluación del dolor se llevó a cabo cada 8 horas tras la cirugía mediante escalas analógicas visuales validadas, con valoraciones entre los 0 y los 10 puntos. Se realizó un ANOVA de las medidas repetidas entre los dos grupos para comparar la evolución del dolor en las 48 horas posteriores a la cirugía. RESULTADOS: La muestra estaba compuesta por un total de 95 pacientes (65% de ellos varones) con una edad media de 9,7 años (DT: 3,14). 41 pacientes fueron tratados con ibuprofeno (grupo 1) y 54 con metamizol (grupo 2). No se hallaron diferencias significativas en lo que respecta al dolor, ni en las comparaciones de las mediciones puntuales, ni en su evolución en las 48 horas posteriores a la cirugía (p= 0,58). Una vez realizado el ajuste correspondiente a la terapia de fluidos recibida, los niños del grupo metamizol tuvieron significativamente más episodios eméticos y necesitaron significativamente más dosis de ondansetrón. CONCLUSIONES: En nuestra cohorte, el ibuprofeno tuvo una eficacia analgésica similar y un mejor perfil emético que el metamizol en el postoperatorio inmediato de la AAP. Se hacen necesarios nuevos estudios prospectivos, adecuadamente controlados y con mayor tamaño muestral que validen estos hallazgos.

Use of metamizole and other non-opioid analgesics in Switzerland between 2014 and 2019: an observational study using a large health insurance claims database.

OBJECTIVE: To investigate claims patterns for metamizole and other non-opioid analgesics in Switzerland. To characterise users of these non-opioid analgesics regarding sex, age, comedications and canton of residence. METHODS: We conducted a retrospective descriptive study using administrative claims data of outpatient prescribed non-opioid analgesics of the Swiss health insurance company Helsana between January 2014 and December 2019. First, we evaluated the number of claims and defined daily doses  per year of metamizole, ibuprofen, diclofenac and paracetamol in adults aged 18 years or over. Second, we characterised new users of these non-opioid analgesics in terms of sex, age, claimed comedications and canton of residence. RESULTS: From 2014 to 2019, among the investigated non-opioid analgesics, metamizole showed the highest increase in claims (+9545 claims, +50%) and defined daily doses (+86,869 defined daily doses, +84%) per 100,000 adults. Metamizole users had the highest median age (62 years [IQR: 44-77]) compared to ibuprofen (47 years [IQR: 33-62]), diclofenac (57 years [IQR: 43-71]) and paracetamol (58 years [IQR: 39-75]) users. Metamizole users also more frequently claimed proton pump inhibitors, anticoagulants, platelet aggregation inhibitors and antihypertensive drugs than users of other non-opioid analgesics. While metamizole was most frequently claimed in German-speaking regions of Switzerland, ibuprofen and paracetamol were most frequently claimed in the French-speaking regions and diclofenac in German- and Italian-speaking regions. CONCLUSION: In Switzerland, metamizole was increasingly claimed between 2014 and 2019. Metamizole was most frequently claimed by older adults and patients with comedications suggestive of underlying conditions, which can be worsened or caused by use of nonsteroidal anti-inflammatory drugs. The lack of studies regarding the effectiveness and safety of metamizole in this population warrants further investigation.

Evaluación prospectiva del perfil emético y la eficacia analgésica del ibuprofeno y el metamizol intravenososen el postoperatorio inmediato de la apendicitis agudapediátrica / Prospective evaluation of the emetogenic profile and analgesic efficacy of intravenous ibuprofen and metamizole in the immediate postoperative period of pediatric acute appendicitis

Introducción: En la literatura existen pocas referencias que comparen las distintas alternativas disponibles para controlar el dolor enel postoperatorio inmediato de la apendicitis aguda pediátrica (AAP).Material y métodos: Comparación prospectiva del perfil anal-gésico y emético del ibuprofeno y el metamizol intravenosos en elpostoperatorio inmediato de la AAP, para lo cual se recurre a unamuestra de pacientes operados en 2021 en nuestro centro. Los participantes fueron reclutados a su llegada a Urgencias, obteniéndoseconfirmación histopatológica del diagnóstico en todos ellos. La evaluación del dolor se llevó a cabo cada 8 horas tras la cirugía medianteescalas analógicas visuales validadas, con valoraciones entre los 0 ylos 10 puntos. Se realizó un ANOVA de las medidas repetidas entrelos dos grupos para comparar la evolución del dolor en las 48 horasposteriores a la cirugía.Resultados: La muestra estaba compuesta por un total de 95 pacientes (65% de ellos varones) con una edad media de 9,7 años (DT:3,14). 41 pacientes fueron tratados con ibuprofeno (grupo 1) y 54 conmetamizol (grupo 2). No se hallaron diferencias significativas en lo querespecta al dolor, ni en las comparaciones de las mediciones puntuales,ni en su evolución en las 48 horas posteriores a la cirugía (p= 0,58). Unavez realizado el ajuste correspondiente a la terapia de fluidos recibida,los niños del grupo metamizol tuvieron significativamente más episodioseméticos y necesitaron significativamente más dosis de ondansetrón.Conclusiones: En nuestra cohorte, el ibuprofeno tuvo una eficaciaanalgésica similar y un mejor perfil emético que el metamizol en elpostoperatorio inmediato de la AAP. Se hacen necesarios nuevos estudiosprospectivos, adecuadamente controlados y con mayor tamaño muestralque validen estos hallazgos.(AU)

Background: Literature comparing different alternatives for paincontrol in the immediate postoperative period of pediatric acute appendicitis (PAA) is scarce.Materials and methods: We prospectively compared the analgesicand emetogenic profile of intravenous ibuprofen and metamizole in theimmediate postoperative period of PAA. For this purpose, we used asample of patients operated on in 2021 in our center. Participants wererecruited on arrival at the Emergency Department and histopathologi-cal confirmation of the diagnosis was obtained in all of them. Pain wasevaluated every 8 hours after the surgery with validated visual analogscales ranging from 0 to 10 points. Repeated measures ANOVA wasused to compare the evolution of pain in the 48 hours after surgerybetween the two groups. Results: The sample included 95 patients (65% males) with a meanage of 9.7 years (sd: 3.14). 41 patients were treated with Ibuprofen(group 1) and 54 with metamizole (group 2). No significant differ-ences were found in the level of pain either in the comparisons of pointmeasurements or in its evolution in the 48 hours after surgery (p= 0.58).After adjusting for the received fluid therapy, children in the metamizolegroup had significantly more emetic episodes and needed significantlymore doses of ondansetron. Conclusions: In our cohort, ibuprofen had a similar analgesic ef-ficacy and a better emetogenic profile than metamizole in the immediatepostoperative period of PAA. Future prospective, adequately controlledstudies with larger sample sizes are needed to validate these findings.(AU)

Neuroendocrine modulation by metamizole and indomethacin: investigating the impact on neuronal markers and GnRH release.

PURPOSE: Some evidence that non-steroidal anti-inflammatory drugs have neuroprotective effects indicates their potential for use in a new field. However, their effects on hormone secretion have yet to be adequately discovered. Therefore, we aimed to evaluate the effects of metamizole and indomethacin on neuronal markers as well as the GnRH expression in the GT1-7 cell line. METHODS: The effects of these drugs on proliferation were evaluated by MTT analysis. The effect of 10-50-250 µM concentrations of the drugs also on the expression of neuronal factors and markers, including NGF, nestin and ßIII Tubulin, and additionally GnRH, was determined by the RT-qPCR method. RESULTS: NGF and nestin mRNA expressions were increased in all concentrations of both metamizole and indomethacin. No changes were detected in ßIII Tubulin. While metamizole showed an increase in GnRH mRNA expression, there was no change at 10 and 50 µM concentrations of indomethacin, but a remarkable decrease was observed at 250 µM concentrations. CONCLUSIONS: The results of our study showing an increase in the expression of neuronal factors reveal that metamizole and indomethacin may have possible neuroprotective effects. Moreover, the effects on the GnRH expression appear to be different. Animal models are required to confirm these effects of NSAIDs on neurons.

Effects of major analgesics on male fertility: A systematic literature review.

OBJECTIVE: To verify, based on a systematic literature review, the effects of the main analgesics on male fertility. DATA SOURCES: The studies were analyzed from the PubMed, SciELO and LILACS databases. STUDY SELECTION: The articles selected for the present review included: cohort studies; cross-sectional studies, clinical trials; complete studies; studies with animal models that addressed the proposed theme and that were published within the stipulated period from March 1, 2013, to March 31, 2023, in English, Portuguese and Spanish. These would later have to go through inclusion stages such as framing the type of study and exclusion criteria. DATA COLLECTION: Author's name, year of publication, study population, number of patients, analgesic, administration time, dose, and effect. CONCLUSIONS: There are in vitro and in vivo studies that link paracetamol and ibuprofen to endocrine and seminal changes that are harmful to male fertility. However, more clinical research is needed to determine the doses and timing of administration that affect fertility. The effects of aspirin on male fertility are still unclear due to the lack of studies and consistent methodologies. There is not enough research on dipyrone and its relationship with male fertility, requiring more studies in this area.

Pharmacokinetics-Based Pediatric Dose Evaluation and Optimization Using Saliva - A Case Study.

Understanding pharmacokinetics (PK) in children is a prerequisite to determine optimal pediatric dosing. As plasma sampling in children is challenging, alternative PK sampling strategies are needed. In this case study we evaluated the suitability of saliva as alternative PK matrix to simplify studies in infants, investigating metamizole, an analgesic used off-label in infants. Six plasma and 6 saliva PK sample collections were scheduled after a single intravenous dose of 10 mg/kg metamizole. Plasma/saliva pharmacometric (PMX) modeling of the active metabolites 4-methylaminoantipyrine (4-MAA) and 4-aminoantipyrine (4-AA) was performed. Various reduced plasma sampling scenarios were evaluated by PMX simulations. Saliva and plasma samples from 25 children were included (age range, 5-70 months; weight range, 8.7-24.8 kg). Distribution of metamizole metabolites between plasma and saliva was without delay. Estimated mean (individual range) saliva/plasma fractions of 4-MAA and 4-AA were 0.32 (0.05-0.57) and 0.57 (0.25-0.70), respectively. Residual variability of 4-MAA (4-AA) in saliva was 47% (28%) versus 17% (11%) in plasma. A simplified sampling scenario with up to 6 saliva samples combined with 1 plasma sample was associated with similar PK parameter estimates as the full plasma sampling scenario. This case study with metamizole shows increased PK variability in saliva compared to plasma, compromising its suitability as single matrix for PK studies in infants. Nonetheless, rich saliva sampling can reduce the number of plasma samples required for PK characterization, thereby facilitating the conduct of PK studies to optimize dosing in pediatric patients.

Management of analgesia in acute pancreatitis: Results of a national survey. / Manejo de la analgesia en la pancreatitis aguda. Resultados de una encuesta nacional.

INTRODUCTION: Acute pancreatitis is one of the main reasons for digestive admissions. Adequate pain treatment is crucial in its management. However, there are hardly any descriptions of the analgesic guidelines used in our setting. METHODS: On-line survey on analgesic management in acute pancreatitis, aimed at attending physicians and residents practising in Spain. RESULTS: Two hundred and nine physicians from 88 centres responded to the survey. Ninety percent were specialists in gastrointestinal medicine and 69% worked in a tertiary centre. The majority (64.4%) do not routinely use scales to measure pain. When choosing a drug, experience in its use was the most important factor. The most commonly prescribed initial treatments are: combination of paracetamol and metamizole (53.5%), paracetamol alone (19.1%) and metamizole alone (17.4%). As rescue: meperidine (54.8%), tramadol (17.8%), morphine chloride (17.8%) and metamizole (11.5%). Continuous perfusion is used in 8.2% of initial treatments. Physicians with >10 years of service use more metamizole as monotherapy (50%), while residents and attending physicians with <10 years of service prescribe it in combination with paracetamol (85%). If progression is needed, morphine chloride and meperidine are mainly used. The speciality of the respondent, the size of the work centre and the unit/service where the patients were admitted did not influence the analgesia prescribed. Satisfaction with pain management reached 7.8/10 (SD 0.98). CONCLUSION: In our setting, metamizole and paracetamol are the most commonly used analgesics as initial pain treatment in acute pancreatitis, and meperidine is the most commonly used rescue analgesic.

Increased Use and Large Variation in Strong Opioids and Metamizole (Dipyrone) for Minor and Major Musculoskeletal Injuries Between 2008 and 2018: An Analysis of a Representative Sample of Swiss Workers.

PURPOSE: Musculoskeletal (MSK) injuries are a major contributing factor for chronic pain. To date, little is known how pain medication use in MSK injuries has changed over time. We assessed pain medication prescription for MSK injuries in a representative sample of Swiss workers between 2008 and 2018. METHODS: Retrospective analysis of the Swiss Accident Insurance Fund (Suva) data. We calculated annual pain medication use, treatment days, and costs associated with pain medication use in minor and major MSK injuries. RESULTS: In total, 1,921,382 cases with MSK injuries with ≥ 1 pain medication were analyzed. Whereas MSK injuries with ≥ 1 pain medication increased by 9.4%, we observed a larger increase in metamizole (+ 254%), strong opioids (+ 88.4%), coxibs (+ 85.8%), and paracetamol (+ 28.1%). Strong opioids were increasingly used in minor (+ 91.4%) and major (+ 88.3%) injuries. The increase in metamizole (+ 390.6%) and coxibs (+ 115.5%) was larger in minor injuries compared to major injuries (+ 238.7% and + 80.6%, respectively). Medical expenses decreased in all medications except for strong opioids where a substantial increase was observed (+ 192.4% in minor; + 34% in major injuries). CONCLUSIONS: We observed a disproportionate increase in metamizole, strong opioids, coxibs, and paracetamol prescriptions even in minor MSK injuries between 2008 and 2018. Whereas treatment costs decreased for all pain medications, there was a substantial increase in strong opioids. A more liberal prescription practice of opioids conflict with current evidence-based practice recommendations and need to be addressed by physicians and policy makers.

Fatal pulmonary hemorrhage, pneumothorax and skin necrosis caused by IRIS to an Aspergillus flavus infection in a young patient with metamizole associated agranulocytosis.

We report the case of a young female with steroid-dependent ulcerative colitis (UC) who developed a complex systemic infection with Aspergillus flavus. This occurred following a UC relapse while vacationing in the Middle East, leading to extended use of metamizole and subsequent agranulocytosis. On her return to Germany, she was hospitalized for neutropenic sepsis and later transferred to our hospital due to persistent cytopenia and suspected Hemophagocytic Lymphohistiocytosis (HLH). Despite initial stabilization with targeted treatment for pulmonary Aspergillus flavus infection, her condition rapidly deteriorated following the onset of an Immune Reconstitution Inflammatory Syndrome (IRIS), which manifested as skin necrosis and pneumothorax after the replenishment of neutrophil granulocytes. The patient eventually died from an unmanageable pulmonary hemorrhage. Microscopy of skin necroses showed a massive presence of Aspergillus flavus, but tissue culture remained negative, suggesting effective antifungal treatment yet delayed phagocytosis due to agranulocytosis. This case underscores the need to consider IRIS in immunosuppressed patients who worsen despite aggressive and appropriately targeted treatment, highlighting its potential beyond the commonly recognized context in HIV-positive patients.

Discovery of GPX4 inhibitors through FP-based high-throughput screening.

Ferroptosis is a form of non-apoptotic cell death, regulated by phospholipid hydroperoxide glutathione peroxidase 4 (GPX4), a selenoprotein with a selenocysteine residue (sec) in the active site. GPX4 is a promising target for cancer cells in therapy-resistant conditions via ferroptosis, which can reduce the level of lipid reactive oxygen species (ROS). So far, all existing GPX4 inhibitors covalently bind to GPX4 via a reactive alkyl chloride moiety or masked nitrile-oxide electrophiles with poor selectivity and pharmacokinetic properties and most were obtained by cell phenotype-based screening. Lacking of effective high-throughput screening methods for GPX4 protein limits the discovery of GPX4 inhibitors. Here, we report a fluorescence polarization (FP)-based high throughput screening (HTS) assay for GPX4-U46C-C10A-C66A in vitro, and found Metamizole sodium from our in-house compound library inhibits GPX4-U46C-C10A-C66A enzyme activity. Structure-activity relationships (SAR) demonstrated the importance of sulfonyl group on interaction between Metamizole sodium and GPX4-U46C-C10A-C66A. Our FP assay could be an effective tool for discovery of GPX4 inhibitors and Metamizole sodium was a potential inhibitor for GPX4 in vitro.

Effects of phenylbutazone, firocoxib, and dipyrone on the diuretic response to furosemide in horses.

BACKGROUND: Treatment with phenylbutazone (nonselective COX inhibitor) decreases the diuretic and natriuretic effects of furosemide by nearly 30% but the effects of COX-2 specific inhibitors (firocoxib) and atypical NSAIDs (dipyrone) are unknown. HYPOTHESIS: Furosemide-induced diuresis after pretreatment with firocoxib or dipyrone is diminished to a lesser extent than after pretreatment with phenylbutazone. ANIMALS: Eight healthy mares. METHODS: Each mare received 4 treatments in a prospective experimental crossover study using a replicated 4 × 4 Latin Square design: furosemide alone (FU), furosemide and phenylbutazone (PB), furosemide and firocoxib (FX), and furosemide and dipyrone (DP). After 24 hours of NSAID treatment at recommended dosages, ureteral catheters were placed for continual urine collection. After a 30-minute baseline collection period, furosemide (1.0 mg/kg, IV) was administered, and urine and blood samples were collected for 4 hours. Data were assessed by repeated measures ANOVA. RESULTS: Four-hour urine volume was (mean ± SD) ~25% less (P < .001) after pretreatment with all NSAIDs (PB 19.1 ± 2.1 mL/kg, FX 17.7 ± 3.5 mL/kg, DP 19.1 ± 3.9 mL/kg), as compared to FU (23.4 ± 5.1 mL/kg) (P < .001), but there were no differences between PB, FX, or DP. Interindividual variability in furosemide diuresis after pretreatment with different NSAIDs was observed. CONCLUSIONS AND CLINICAL IMPORTANCE: Though COX-2 selective NSAIDs and dipyrone might have less severe or fever gastrointestinal adverse effects in horses, our data suggest minimal differences in effects on furosemide-induced diuresis, and possibly, risk of nephrotoxicosis.

Pharmacotherapeutic monitoring of dipyrone in northeastern Brazilian donkeys (Equus asinus).

This study aimed to monitor the effects of dipyrone following multiple administrations in northeastern donkeys. Ten castrated male donkeys, aged 6.4 ± 3 years and weighing 130.6 ± 9.8 kg, were administered dipyrone (25 mg/kg IV) every 12 h, resulting in six administrations (D1 to D6) per animal. Blood samples were collected over a 72 h monitoring period. A validated UHPLC-MS/MS method was employed to determine the plasma concentrations of the 4- methylaminoantipyrine (4-MAA) and 4-aminoantipyrine (4-AA). The calculated pharmacokinetic variables of 4-MAA after D1 and D6 were, respectively: Cmax (µg/mL) = 163.60 ± 179.72 and 178.79 ± 196.94; T1/2beta (h) = 2.65 ± 0.65 and 3.37 ± 1.03; and AUC0-t (µg/mL × h) = 240.38 ± 130.87 and 373.52 ± 78.85. The same variables for 4-AA were: Cmax, (µg/mL) = 0.44 ± 0.27 and 0.90 ± 0.31, T1/2beta (h) = 14.77 ± 13.13 and 35.97 and AUC0-t (µg/mL × h) = 3.20 ± 0.43 and 27.73 ± 11.99. Concentrations of 4-MAA exceeded the minimum concentration required for 50% inhibition of cyclooxygenases 1 and 2. However, an accumulation of 4-AA, was observed. Further clinical studies are necessary to ascertain the implications of these findings on the pharmacodynamic response to dipyrone in northeastern donkeys.

Application of analgesics in emergency services in Germany: a survey of the medical directors.

ABSTRAC: BACKGROUND: Treatment of acute pain is an essential element of pre-hospital care for injured and critically ill patients. Clinical studies indicate the need for improvement in the prehospital analgesia. OBJECTIVE: The aim of this study is to assess the current situation in out of hospital pain management in Germany regarding the substances, indications, dosage and the delegation of the use of analgesics to emergency medical service (EMS) staff. MATERIAL AND METHODS: A standardized survey of the medical directors of the emergency services (MDES) in Germany was carried out using an online questionnaire. The anonymous results were evaluated using the statistical software SPSS (Chi-squared test, Mann-Whitney-U test). RESULTS: Seventy-seven MDES responsible for 989 rescue stations and 397 EMS- physician bases in 15 federal states took part in this survey. Morphine (98.7%), Fentanyl (85.7%), Piritramide (61%), Sufentanil (18.2%) and Nalbuphine (14,3%) are provided as opioid analgesics. The non-opioid analgesics (NOA) including Ketamine/Esketamine (98,7%), Metamizole (88.3%), Paracetamol (66,2%), Ibuprofen (24,7%) and COX-2-inhibitors (7,8%) are most commonly available. The antispasmodic Butylscopolamine is available (81,8%) to most rescue stations. Fentanyl is the most commonly provided opioid analgesic for treatment of a traumatic pain (70.1%) and back pain (46.8%), Morphine for visceral colic-like (33.8%) and non-colic pain (53.2%). In cases of acute coronary syndrome is Morphine (85.7%) the leading analgesic substance. Among the non-opioid analgesics is Ketamine/Esketamine (90.9%) most frequently provided to treat traumatic pain, Metamizole for visceral colic-like (70.1%) and non-colic (68.6%) as well as back pain (41.6%). Butylscopolamine is the second most frequently provided medication after Metamizole for "visceral colic-like pain" (55.8%). EMS staff (with or without a request for presence of the EMS physician on site) are permitted to use the following: Morphine (16.9%), Piritramide (13.0%) and Nalbuphine (10.4%), and of NOAs for (Es)Ketamine (74.1%), Paracetamol (53.3%) and Metamizole (35.1%). The dosages of the most important and commonly provided analgesic substances permitted to independent treatment by the paramedics are often below the recommended range for adults (RDE). The majority of medical directors (78.4%) of the emergency services consider the independent application of analgesics by paramedics sensible. The reason for the relatively rare authorization of opioids for use by paramedics is mainly due to legal (in)certainty (53.2%). CONCLUSION: Effective analgesics are available for EMS staff in Germany, the approach to improvement lies in the area of application. For this purpose, the adaptations of the legal framework as well as the creation of a guideline for prehospital analgesia are useful.

Development of a Lateral Flow Immunoassay Based on a Highly Specific Monoclonal Antibody To Detect 4-Methylaminoantipyrine.

To avoid false-positive results in immunoassays due to cross-reactivity of antibodies with structural analogues, especially metabolites of target compounds, the preparation of highly specific antibodies is crucial. Preserving the characteristic structure of a target compound when designing a hapten is important when preparing highly specific antibodies. Here, we designed a novel hapten, 4-(((1,5-dimethyl-3-oxo-2-phenyl-2,3-dihydro-1H-pyrazol-4yl)amino)methyl)benzoic acid, named AA-BA, to improve the specificity of antibodies for detection of 4-methylaminoantipyrine (MAA), a residual marker of dipyrone, an important antipyretic-analgesic and anti-inflammatory drug. The structural features of the hapten remained almost the same as those of MAA. After experimental validation, monoclonal antibody 6A4 (mAb 6A4) was prepared with the half maximal inhibitory concentration (IC50) value of 4.03 ng/mL and negligible cross-reactivity with dipyrone metabolites and other antibiotics. In addition, a specific lateral flow immunoassay (LFA) strip based on colloidal gold was developed for screening MAA with a cutoff value of 25 ng/mL in milk. The developed LFA is a useful tool for rapid and accurate detection of MAA.

Use of meloxicam with or without dipyrone in non-surgical embryo recovery in hair sheep: Effects on animal welfare.

The aim of this study was to determine the effectiveness of meloxicam with or without dipyrone on the welfare of ewes subjected to non-surgical embryo recovery (NSER). Two studies were carried out using 51 multiparous Santa Inês ewes. All animals received a standard oestrous synchronization treatment and a superovulatory protocol. In Study 1, 12 ewes received meloxicam (GM) before cervical transposition (1 mg kg-1 , i.v.), repeated 24 h after (1 mg kg-1 , i.m.), while the other 10 received a saline solution, remaining as a control group (GC1). In Study 2, ewes were allocated into a group of 15 ewes treated as GM of Study 1 associated with dipyrone (GMD; 50 mg kg-1 , i.m.) before cervical transposition, 12 h, and 24 h after, or a control group (GC2) of 14 ewes treated with saline solution. In both studies, heart and respiratory rates (RR), cortisol, glucose, total proteins, albumin and globulins blood concentration were recorded before sedation (BS), after sedation (AS), after cervical transposition, immediately after collection (IAC), and 0.5, 1.5, 3, 6, 12, 24 and 48 h after embryo collection (hAC). In Study 1, RR tended to be greater in GC1 (p = .08), serum total proteins and globulins values were lower and serum albumin values were greater in this group than GM (p = .003, p < .0001, and p < .0001, respectively). In Study 2, treatment of GMD tended to reduce the glycaemia at AS (p = .052) and reduced it at 3hAC (p < .0001), and 6hAC (p = .03). It also tended to reduce cortisol concentrations (p = .10). The other variables varied with NSER without interaction with the experimental treatments. In conclusion, in this study condition, NSER in sheep induced transient changes indicative of stress and possibly pain, therefore, affecting animal welfare. The administration of meloxicam was ineffective to reduce those responses, and the association of dipyrone had only slight effects without modifying the main welfare indicative responses in ewes subjected to NSER.