Metamizole use by Latino immigrants: a common and potentially harmful home remedy

Delivering on sustainable development goals in wastewater reuse for agriculture: Initial prioritization of emerging pollutants in the Tula Valley, Mexico

Wastewater reuse for agricultural irrigation is a widespread beneficial practice, in line with the sustainable development goals. However, contaminants of emerging concern (CECs) present in wastewater, such as pharmaceuticals, pose an environmental risk. The Tula Valley in Mexico is one of the world's largest agricultural areas reusing wastewater for agriculture. However, no untargeted CEC monitoring has been undertaken there, limiting the information available to prioritise local environmental risk assessment. Furthermore, CEC environmental presence in the Global South remains understudied, compared to the Global North. There is a risk that current research efforts focus on CECs predominantly found in the Global North, leading to strategies that may not be appropriate for the Global South where the pollution profile may be different. To address these knowledge gaps, a sampling campaign at five key sites in the Tula Valley was undertaken and samples analysed using multi-residue targeted and untargeted liquid chromatography mass spectrometry methods. Using the targeted data, ten CECs were found to be of environmental risk for at least one sampling site: 4‑tert-octylphenol, acetaminophen, bezafibrate, diclofenac, erythromycin, levonorgestrel, simvastatin, sulfamethoxazole, trimethoprim and tramadol as well as total estrogenicity (combination of three steroid hormones). Six of these have not been previously quantified in the Tula Valley. Over one hundred pollutants never previously measured in the area were identified through untargeted analysis supported by library spectrum match. Examples include diclofenac and carbamazepine metabolites and area-specific pollutants such as the herbicide fomesafen. This research contributes to characterising the presence of CECs in the Global South, as well as providing site-specific data for the Tula Valley.

Medications Without Borders: Themes in Caregiver Administration of Imported Medications in Pediatrics

OBJECTIVE

This study aimed to identify motivating factors in why parents administer imported medications to their children.

METHODS

In this qualitative study, we enrolled caregivers of patients younger than 18 years who presented for care at a pediatric emergency department. The study team conducted face-to-face interviews with caregivers in the emergency department and used a semistructured question guide to probe for themes regarding the use of imported medications in children. Interviews were recorded, transcribed, translated if necessary, and coded. We applied grounded theory methodology to assess for themes and adapted the Andersen model of health care utilization to provide a framework for the identified themes.

RESULTS

We completed 30 interviews, 9 of which were conducted in Spanish. Themes surrounding imported medication usage were categorized into predisposing, enabling, and need factors. Predisposing factors included perception that an ill child needs medication to get better, perception of medication quality, and past experiences with medications. Enabling factors included proximity to foreign countries, cost, limited access to primary care, and convenience of obtaining medications. Need factors included utilization of foreign medications for a "simple illness" and utilization of foreign care for a "second opinion."

CONCLUSIONS

Our study used qualitative methodology to gain important insights into the caregiver experience of a diverse patient population. We identify themes not previously published in the medication importation literature. These concepts can provide insights in educational strategies aimed at mitigating the potential dangers of imported medication use in pediatrics.

Metamizole Use in Children: Analysis of Drug Utilisation and Adverse Drug Reactions at a German University Hospital between 2015 and 2020

BACKGROUND

Metamizole use is controversially discussed due to its potentially serious adverse drug reactions (ADRs). In Germany, however, it remains a popular analgesic and antipyretic drug.

OBJECTIVE

The aim of this study was to discuss the safety profile of metamizole in children by analysing the inpatient prescription patterns and presenting the metamizole-related ADRs at a paediatric hospital between 2015 and 2020.

METHODS

Metamizole utilisation data were retrospectively analysed from electronic medical records. ADRs were prospectively recorded via the hospital's stimulated reporting system and analysed accordingly. Patients aged < 18 years admitted to one of the general wards of the department of paediatrics and adolescent medicine of a German university hospital between June 2015 and May 2020 who received at least one drug therapy within their inpatient stay were included in the analysis. Causality of ADRs was rated according to the World Health Organisation causality assessment.

RESULTS

In 31.7% (3759/11,857) of the inpatient stays of 7809 patients, metamizole was administered. Metamizole exposure was highest in adolescents (37.9%) and lowest in newborns (9.9%). Overall, metamizole was administered parenterally in about 90%. Three cases of agranulocytosis, one allergic shock and one rash with possible or higher causality to metamizole treatment were reported. Three of these occurred prior to hospitalisation. All patients recovered without remaining harm.

DISCUSSION

Metamizole is commonly used in paediatric inpatients in Germany. Serious ADRs occur but rarely. Continuous monitoring of drug therapy through, for example, stimulated reporting systems ensures that serious ADRs are detected, and appropriate interventions can be introduced.

Drug-Induced Liver Injury: Highlights and Controversies in the Recent Literature

Drug-induced liver injury (DILI) remains an important, yet challenging diagnosis for physicians. Each year, additional drugs are implicated in DILI and this year was no different, with more than 1400 articles published on the subject. This review examines some of the most significant highlights and controversies in DILI-related research over the past year and their implications for clinical practice. Several new drugs were approved by the US Food and Drug Administration including a number of drugs implicated in causing DILI, particularly among the chemotherapeutic classes. The COVID-19 pandemic was also a major focus of attention in 2020 and we discuss some of the notable aspects of COVID-19-related liver injury and its implications for diagnosing DILI. Updates in diagnostic and causality assessments related to DILI such as the Roussel Uclaf Causality Assessment Method are included, mindful that there is still no single biomarker or diagnostic tool to unequivocally diagnose DILI. Glutamate dehydrogenase received renewed attention as being more specific than alanine aminotransferase. There were a few new reports of previously unrecognized hepatotoxins, including immune modulators and novel gene therapy drugs that we highlight. Updates and new developments of previously described hepatotoxins, such as immune checkpoint inhibitors and anti-tuberculosis drugs are reviewed. Finally, novel technologies such as organoid culture systems to better predict DILI preclinically may be coming of age and determinants of hepatocyte loss, such as calculating P_ALT are poised to improve our current means of estimating DILI severity and the risk of acute liver failure.

Arylamine N-acetyltransferase acetylation polymorphisms: paradigm for pharmacogenomic-guided therapy- a focused review

INTRODUCTION

The N-acetylation polymorphism has been the subject of comprehensive reviews describing the role of arylamine N-acetyltransferase 2 (NAT2) in the metabolism of numerous aromatic amine and hydrazine drugs.

AREAS COVERED

We describe and review data that more clearly defines the effects of NAT2 haplotypes and genotypes on the expression of acetylator phenotype towards selected drugs within human hepatocytes in vitro, within human hepatocyte cultures in situ, and clinical measures such as bioavailability, plasma metabolic ratios of parent to N-acetyl metabolite, elimination rate constants and plasma half-life, and/or clearance determinations in human subjects. We review several drugs (isoniazid, hydralazine, sulfamethazine, amifampridine, procainamide, sulfasalazine, amonafide and metamizole) for which NAT2 phenotype-guided therapy may be important. The value of pharmacogenomics-guided isoniazid therapy for the prevention and treatment of tuberculosis is presented as a paradigm for NAT2 phenotype-dependent dosing strategies.

EXPERT OPINION

Studies in human subjects and cryopreserved human hepatocytes show evidence for rapid, intermediate and slow acetylator phenotypes, with further data suggesting genetic heterogeneity within the slow acetylator phenotype. Incorporation of more robust NAT2 genotype/phenotypes relationships, including genetic heterogeneity within the slow acetylator phenotype, should lead to further advancements in both health outcomes and cost benefit for prevention and treatment of tuberculosis.

Reactive Metamizole Metabolites Enhance the Toxicity of Hemin on the ATP Pool in HL60 Cells by Inhibition of Glycolysis

Metamizole is an analgesic, whose pharmacological and toxicological properties are attributed to N-methyl-aminoantipyrine (MAA), its major metabolite. In the presence of heme iron, MAA forms reactive metabolites, which are toxic for granulocyte precursors. Since decreased cellular ATP is characteristic for MAA-associated toxicity, we studied the effect of MAA with and without hemin on energy metabolism of HL60 cells, a granulocyte precursor cell line. The combination MAA/hemin depleted the cellular ATP stronger than hemin alone, whereas MAA alone was not toxic. This decrease in cellular ATP was observed before plasma membrane integrity impairment. MAA/hemin and hemin did not affect the proton leak but increased the maximal oxygen consumption by HL60 cells. This effect was reversed by addition of the radical scavenger N-acetylcysteine. The mitochondrial copy number was not affected by MAA/hemin or hemin. Hemin increased mitochondrial superoxide generation, which was not accentuated by MAA. MAA decreased cellular ROS accumulation in the presence of hemin. In cells cultured in galactose (favoring mitochondrial ATP generation), MAA/hemin had less effect on the cellular ATP and plasma membrane integrity than in glucose. MAA/hemin impaired glycolysis more than hemin or MAA alone, and N-acetylcysteine blunted this effect of MAA/hemin. MAA/hemin decreased protein expression of pyruvate kinase more than hemin or MAA alone. In conclusion, cellular ATP depletion appears to be an important mechanism of MAA/hemin toxicity on HL60 cells. MAA itself is not toxic on HL60 cells up to 100 µM but boosts the inhibitory effect of hemin on glycolysis through the formation of reactive metabolites.

Metamizole: An underrated agent causing severe idiosyncratic drug-induced liver injury

Aims

Drug‐induced liver injury (DILI) is a heterogenous entity leading to liver damage. We have analysed the frequency, biochemical and histological patterns and clinical courses of DILI cases due to metamizole at our tertiary care centre in Hamburg, Germany.

Methods

Consecutive patients with DILI who presented to our clinic were analysed retrospectively. Causes of acute hepatitis other than DILI were excluded.

Results

In total, 154 DILI cases were admitted to our centre from 2008 to 2017. After phenprocoumon, metamizole was the second most frequent putative agent causing DILI (23 of all 154 DILI cases, 14,9%). The biochemical pattern on admission of metamizole‐induced DILI cases was hepatocellular with median levels of alanine transaminase (779 U/L, 64–3532 U/L) by far exceeding median alkaline phosphatase levels (131 U/L, 42–578 U/L). In 17 of the 23 cases (74%) liver biopsy was performed. Moderate to severe inflammatory histological activity and severe centrilobular necrosis (>30%) was present in 76.5 and 35.3%, respectively. Metamizole was involved in 2 DILI cases progressing to acute liver failure, then receiving liver transplantation and still alive at time of assessment. Our data were supported by re‐exposure in 4 patients. Furthermore, a database search for metamizole‐induced liver injury in the European Medicines Agency's database identified about 300 reports on suspected metamizole‐induced DILI in Europe.

Conclusion

Elevation of liver enzymes or acute liver failure are not mentioned in the German drug label of metamizole as potential side effects. Our study reveals that in Germany and Europe, metamizole is a frequent and underrated agent causing DILI.

The use of dipyrone (metamizol) as an analgesic in children: What is the evidence? A review

Dipyrone has analgesic, spasmolytic, and antipyretic effects and is used to treat pain. Due to a possible risk of agranulocytosis with the use of dipyrone, it has been banned in a number of countries. The most commonly used data for the use of dipyrone are related to adults. Information relating to the use of dipyrone in children is scarce. Given the potential added value of dipyrone in the treatment of pain, a review of the literature was conducted to obtain more insight into the analgesic efficacy of dipyrone in children as well as the safety of dipyrone in terms of adverse events. A literature search was done for original articles (in English, German, or Spanish language) which met the following criteria: the use of dipyrone for pain and children up to the age of 17 years old. All titles and abstracts retrieved were reviewed, independently, by two of the authors, for their suitability for inclusion. The references of the selected articles were also checked for additional relevant papers. The publications were categorized into case reports, observational studies, or randomized controlled trials. To assess the methodological quality of the studies, the Jadad score was used. In the limited available data, the analgesic efficacy of intravenous dipyrone appears similar to that of intravenous paracetamol. Evidence is lacking to support the claim that dipyrone is equivalent or even superior to Non-Steroid-Anti-Inflammatory-Drugs in pediatric pain. While the absolute risk of agranulocytosis with dipyrone in children, based on available literature, cannot be determined, case reports suggest that this risk is not negligible.

Inappropriate Prescribing in Older Hospitalized Adults: A Comparison of Medical Specialties

OBJECTIVES

To evaluate the prevalence and number of potentially inappropriate medications (PIMs) in hospitalized older adults, comparing prescription patterns of medical specialties.

DESIGN

Retrospective cohort study.

SETTING

Tertiary general hospital.

PARTICIPANTS

All older adults hospitalized from January through May 2015 (N = 1,900).

MEASUREMENTS

Information on medications prescribed during the first and last days of hospitalization was collected and evaluated regarding PIMs using Beers and Screening Tool of Older People's Prescriptions (STOPP) criteria. Medical specialties (internal medicine, cardiology, gastroenterology, infectious disease, nephrology, neurology, pneumology) were compared regarding the prevalence of PIMs and the increase in the number of PIMs during hospitalization.

RESULTS

The number of individuals with PIMs increased significantly according to both criteria (62.3% to 66.6% according to Beers criteria, 43.4% to 50.0% according to STOPP criteria). The most common PIMs were sliding-scale insulin (26.9%), clonazepam (9.5%), and periciazine (6.4%) using Beers criteria and spironolactone (10.3%), acetylsalicylic acid (9.8%), and periciazine (8.7%) using STOPP criteria. Neurology, infectious disease, and pneumology had the highest numbers of PIMs, and neurology, pneumology, and cardiology had a greater increase in PIMs during hospitalization than the other specialties.

CONCLUSION

This study demonstrates the high and growing prevalence of PIMs in the hospital environment, according to Beers and STOPP criteria. Educational measures and specific pharmaceutical interventions for each specialty are needed to change this situation.

Analgesic medication with dipyrone in patients with coronary artery disease: Relation to MACCE

BACKGROUND

The non-opioid analgesic dipyrone can trigger life-threatening blood formation disorders. However, it is frequently used, as many patients with coronary artery disease (CAD) rely on non-opioid analgesics to relieve pain. In this study, we investigated the incidence of death, myocardial infarction (MI) or stroke in CAD patients with aspirin and dipyrone comedication as compared to aspirin-alone.

METHODS

We conducted an observational pilot study in 72 CAD patients with aspirin ± dipyrone comedication in the department of cardiology of the University Hospital Düsseldorf. The primary end point was a composite of death, myocardial infarction (MI) or stroke. The secondary end points were the components of the primary end point. The median follow-up period was 3.2years.

RESULTS

The primary end point occurred 67% of patients in the aspirin+dipyrone group as compared to 31% in the aspirin-alone group (odds ratio [OR] 4.5, 95% confidence interval [CI] 1.7 to 12.3; P=0.0028;). All-cause mortality was significantly higher in the aspirin+dipyrone group (44%) than the aspirin-alone group (22%; OR 2.8, 95% CI 1.01 to 7.8; P=0.049). Ischemic events (MI and stroke) were more frequent in the aspirin+dipyrone group as compared to the aspirin alone group as well (OR 4, 95% CI 1.1 to 14; P=0.03).

CONCLUSION

In this hypothesis generating pilot analysis, dipyrone medication in aspirin treated coronary artery disease patients is associated with an increased cumulative incidence of death, MI or stroke as well as all-cause mortality and ischemic events. These data have to be confirmed in larger registries and trials.

CLINICAL TRIAL REGISTRATION

http://clinicaltrials.gov/ct2/show/NCT01402804; Identifier: NCT01402804; Date of registration: July 25, 2011.

The Pain Experience of Hispanic Americans: A Critical Literature Review and Conceptual Model

Although the Hispanic population is a burgeoning ethnic group in the United States, little is known about their pain-related experience. To address this gap, we critically reviewed the existing literature on pain experience and management among Hispanic Americans (HAs). We focused our review on the literature on nonmalignant pain, pain behaviors, and pain treatment seeking among HAs. Pain management experiences were examined from HA patients' and health care providers' perspectives. Our literature search included variations of the term "Hispanic" with "AND pain" in PubMed, Embase, Web of Science, ScienceDirect, and PsycINFO databases. A total of 117 studies met our inclusion criteria. We organized the results into a conceptual model with separate categories for biological and/or psychological and sociocultural and/or systems-level influences on HAs' pain experience, response to pain, and seeking and receiving pain care. We also included information on health care providers' experience of treating HA patients with pain. For each category, we identified future areas of research. We conclude with a discussion of limitations and clinical implications.

PERSPECTIVE

In this critical review of the literature we examined the pain and management experiences of the HA population. We propose a conceptual model, which highlights findings from the existing literature and future areas of research.

Single dose dipyrone (metamizole) for acute postoperative pain in adults

BACKGROUND

Dipyrone (metamizole) is a nonsteroidal anti-inflammatory drug used in some countries to treat pain (postoperative, colic, cancer, and migraine); it is banned in other countries because of an association with life-threatening blood disorders. This review replaces a 2010 Cochrane review that has been withdrawn.

OBJECTIVES

To assess the analgesic efficacy and associated adverse events of single dose dipyrone for moderate to severe acute postoperative pain using methods that permit comparison with other analgesics evaluated in standardised trials using almost identical methods and outcomes.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, EMBASE, and LILACS to 11 August 2015; the Oxford Pain Relief Database; two clinical trial registries; and the reference lists of articles.

SELECTION CRITERIA

We included randomised, double-blind, placebo-controlled trials of single dose dipyrone for relief of established moderate to severe postoperative pain in adults. We accepted oral, rectal, intramuscular, and intravenous routes of administration.

DATA COLLECTION AND ANALYSIS

Two review authors independently considered studies for inclusion in the review, assessed risk of bias, and extracted data. We used summed total pain relief or pain intensity difference (TOTPAR or SPID) over four to six hours to calculate the number of participants achieving at least 50% pain relief. From derived results, we calculated the risk ratio and number needed to treat for an additional beneficial outcome (NNT), with 95% confidence intervals (CI), for one participant to experience at least 50% pain relief over four to six hours compared to placebo. We looked at use of rescue medication and time to use of rescue medication as additional measures of efficacy. We also looked for information on adverse events and withdrawals.

MAIN RESULTS

We included eight studies, involving 809 participants, comparing oral dipyrone 500 mg (143 participants), oral dipyrone 1000 mg (57 participants), and intramuscular dipyrone 2000 mg (35 participants) with placebo (236 participants). In addition to placebo, all studies used active controls (ibuprofen, paracetamol, aspirin, flurbiprofen, ketoprofen; 338 participants). Seven studies used the oral route of administration, and one study used the intramuscular route. The mean age ranged from 23 to 62 years. Six studies included both men and women, and two studies included only women. All the studies were small, but were otherwise of moderate to good quality.Over 70% of participants experienced our primary outcome of at least 50% pain relief over four to six hours with oral dipyrone 500 mg compared to 30% with placebo (five studies, 288 participants; NNT 2.4 (95% CI 1.8 to 3.1)) (moderate quality evidence). There were insufficient data to assess other doses or routes of administration of dipyrone.Fewer participants needed rescue medication within four to six hours with dipyrone 500 mg than with placebo (7% with dipyrone versus 34% with placebo; four studies, 248 participants) (low quality evidence).The data on numbers of participants experiencing any adverse event was inconsistently reported and no analysis was possible. No serious adverse events or adverse event withdrawals were reported (very low quality evidence).There were too few data to compare dipyrone directly with other active treatments.

AUTHORS' CONCLUSIONS

Based on very limited information, a single dose of dipyrone 500 mg provides good pain relief to about 70% of people treated, compared to about 30% with placebo. For every five people given dipyrone 500 mg, two people would experience this level of pain relief over four to six hours who would not have done with placebo, and fewer people would need rescue medication.We were unable to compare dipyrone directly with other active treatments, or to assess the effects of different doses or routes of administration, or the number of participants experiencing adverse events, because of insufficient data and inadequate reporting.

[Pediatric perioperative systemic pain therapy: Austrian interdisciplinary recommendations on pediatric perioperative pain management]

BACKGROUND

Many analgesics used in adult medicine are not licensed for pediatric use. Licensing limitations do not, however, justify that children are deprived of a sufficient pain therapy particularly in perioperative pain therapy. The treatment is principally oriented to the strength of the pain. Due to the degree of pain caused, intramuscular and subcutaneous injections should be avoided generally.

NON-OPIOIDS

The basis of systemic pain therapy for children are non-opioids and primarily non-steroidal anti-inflammatory drugs (NSAIDs). They should be used prophylactically. The NSAIDs are clearly more effective than paracetamol for acute posttraumatic and postoperative pain and additionally allow economization of opioids. Severe side effects are rare in children but administration should be carefully considered especially in cases of hepatic and renal dysfunction or coagulation disorders. Paracetamol should only be taken in pregnancy and by children when there are appropriate indications because a possible causal connection with bronchial asthma exists. To ensure a safe dosing the age, body weight, duration of therapy, maximum daily dose and dosing intervals must be taken into account. Dipyrone is used in children for treatment of visceral pain and cholic. According to the current state of knowledge the rare but severe side effect of agranulocytosis does not justify a general rejection for short-term perioperative administration.

OPIOIDS

In cases of insufficient analgesia with non-opioid analgesics, the complementary use of opioids is also appropriate for children of all age groups. They are the medication of choice for episodes of medium to strong pain and are administered in a titrated form oriented to effectiveness. If severe pain is expected to last for more than 24 h, patient-controlled anesthesia should be implemented but requires a comprehensive surveillance by nursing personnel.

KETAMINE

Ketamine is used as an adjuvant in postoperative pain therapy and is recommended for use in pediatric sedation and analgosedation.

WITHDRAWN: Single dose dipyrone for acute postoperative pain

BACKGROUND

Dipyrone (metamizole) is a non‐steroidal anti‐inflammatory drug used in some countries to treat pain (postoperative, colic, cancer, and migraine); it is banned in others because of an association with life‐threatening blood agranulocytosis. This review updates a 2001 Cochrane review, and no relevant new studies were identified, but additional outcomes were sought.

OBJECTIVES

To assess the efficacy and adverse events of single dose dipyrone in acute postoperative pain.

SEARCH METHODS

The earlier review searched CENTRAL, MEDLINE, EMBASE, LILACS and the Oxford Pain Relief Database to December 1999. For the update we searched CENTRAL, MEDLINE,EMBASE and LILACS to February 2010.

SELECTION CRITERIA

Single dose, randomised, double‐blind, placebo or active controlled trials of dipyrone for relief of established moderate to severe postoperative pain in adults. We included oral, rectal, intramuscular or intravenous administration of study drugs.

DATA COLLECTION AND ANALYSIS

Studies were assessed for methodological quality and data extracted by two review authors independently. Summed total pain relief over six hours (TOTPAR) was used to calculate the number of participants achieving at least 50% pain relief. Derived results were used to calculate, with 95% confidence intervals, relative benefit compared to placebo, and the number needed to treat (NNT) for one participant to experience at least 50% pain relief over six hours. Use and time to use of rescue medication were additional measures of efficacy. Information on adverse events and withdrawals was collected.

MAIN RESULTS

Fifteen studies tested mainly 500 mg oral dipyrone (173 participants), 2.5 g intravenous dipyrone (101), 2.5 g intramuscular dipyrone (99); fewer than 60 participants received any other dose. All studies used active controls (ibuprofen, paracetamol, aspirin, flurbiprofen, ketoprofen, dexketoprofen, ketorolac, pethidine, tramadol, suprofen); eight used placebo controls. Over 70% of participants experienced at least 50% pain relief over 4 to 6 hours with oral dipyrone 500 mg compared to 30% with placebo in five studies (288 participants; NNT 2.4 (1.9 to 3.2)). Fewer participants needed rescue medication with dipyrone (7%) than with placebo (34%; four studies, 248 participants). There was no difference in participants experiencing at least 50% pain relief with 2.5 g intravenous dipyrone and 100 mg intravenous tramadol (70% vs 65%; two studies, 200 participants). No serious adverse events were reported.

AUTHORS' CONCLUSIONS

Based on very limited information, single dose dipyrone 500 mg provides good pain relief to 70% of patients. For every five individuals given dipyrone 500 mg, two would experience this level of pain relief who would not have done with placebo, and fewer would need rescue medication, over 4 to 6 hours.

Anaesthetic Management of a 1-Month-Old Puppy Undergoing Lateral Thoracotomy for Vascular Ring Anomaly Correction

A 1-month-old male flat-coated retriever was anaesthetized for correction of oesophageal constriction caused by a vascular ring anomaly. Anaesthesia was uneventfully induced with intravenous fentanyl, diazepam, and propofol and maintained with isoflurane in oxygen and air. An intercostal block with bupivacaine and lidocaine was performed, and additional analgesia with an infusion of fentanyl was provided. Fluid therapy consisted in 5% glucose in lactated Ringer’s solution and hetastarch 6%, which proved adequate to maintain normoglycemia and normovolemia. A lateral thoracotomy was performed, and the ligamentum arteriosum was ligated. Intraoperatively, heart rate (HR) varied between 120 and 180 beats min−1without accompanying changes in blood pressure. No arrhythmias were observed or bleeding occurred. The dog recovered uneventfully. Postoperative analgesia consisted in fentanyl infusion adjusted to the patient's requirement and metamizol. This paper describes for the first time the use of balanced anaesthesia and multimodal analgesia in a paediatric dog undergoing thoracotomy.

Single dose dipyrone for acute postoperative pain

BACKGROUND

Dipyrone (metamizole) is a non-steroidal anti-inflammatory drug used in some countries to treat pain (postoperative, colic, cancer, and migraine); it is banned in others because of an association with life-threatening blood agranulocytosis. This review updates a 2001 Cochrane review, and no relevant new studies were identified, but additional outcomes were sought.

OBJECTIVES

To assess the efficacy and adverse events of single dose dipyrone in acute postoperative pain.

SEARCH STRATEGY

The earlier review searched CENTRAL, MEDLINE, EMBASE, LILACS and the Oxford Pain Relief Database to December 1999. For the update we searched CENTRAL, MEDLINE,EMBASE and LILACS to February 2010.

SELECTION CRITERIA

Single dose, randomised, double-blind, placebo or active controlled trials of dipyrone for relief of established moderate to severe postoperative pain in adults. We included oral, rectal, intramuscular or intravenous administration of study drugs.

DATA COLLECTION AND ANALYSIS

Studies were assessed for methodological quality and data extracted by two review authors independently. Summed total pain relief over six hours (TOTPAR) was used to calculate the number of participants achieving at least 50% pain relief. Derived results were used to calculate, with 95% confidence intervals, relative benefit compared to placebo, and the number needed to treat (NNT) for one participant to experience at least 50% pain relief over six hours. Use and time to use of rescue medication were additional measures of efficacy. Information on adverse events and withdrawals was collected.

MAIN RESULTS

Fifteen studies tested mainly 500 mg oral dipyrone (173 participants), 2.5 g intravenous dipyrone (101), 2.5 g intramuscular dipyrone (99); fewer than 60 participants received any other dose. All studies used active controls (ibuprofen, paracetamol, aspirin, flurbiprofen, ketoprofen, dexketoprofen, ketorolac, pethidine, tramadol, suprofen); eight used placebo controls.Over 70% of participants experienced at least 50% pain relief over 4 to 6 hours with oral dipyrone 500 mg compared to 30% with placebo in five studies (288 participants; NNT 2.4 (1.9 to 3.2)). Fewer participants needed rescue medication with dipyrone (7%) than with placebo (34%; four studies, 248 participants). There was no difference in participants experiencing at least 50% pain relief with 2.5 g intravenous dipyrone and 100 mg intravenous tramadol (70% vs 65%; two studies, 200 participants). No serious adverse events were reported.

AUTHORS' CONCLUSIONS

Based on very limited information, single dose dipyrone 500 mg provides good pain relief to 70% of patients. For every five individuals given dipyrone 500 mg, two would experience this level of pain relief who would not have done with placebo, and fewer would need rescue medication, over 4 to 6 hours.

Pain coping in Latino populations

Although there has been a rapid increase in Latino populations in the United States over the last 10 years, health research with Latino cultural groups is sorely lacking. In the area of pain-coping research, one consequence of the limited research is that very little is known about pain coping among Latinos. The purpose of this paper is to review the existing literature on pain coping in Latino populations, and to propose new directions for the future study of pain coping in Latino populations. This review is divided into 4 sections. In the first section, the challenges of defining Latino populations are discussed. In the second section, the current literature on pain coping in Latinos is reviewed. Third, we discuss the implications of existing findings for pain-coping assessment and pain treatment. Finally, we offer ideas for future research on pain coping in Latino populations.

PERSPECTIVE

In this review article, we identify gaps in our current understanding of pain coping in Latino cultural groups, and associated implications for pain assessment and treatment. We also highlight potential directions for future pain-coping research with Latino populations.

The importance of cultural competency in general pediatrics

PURPOSE OF REVIEW

There is a growing awareness of the importance of cultural competency in pediatrics. The authors review the most recent studies that examine the impact of cultural competency on general pediatric care, explore cultural beliefs and practices affecting clinical care, and describe culturally sensitive interventions designed to address racial/ethnic health disparities.

RECENT FINDINGS

The beneficial effects of cultural competency embrace health outcomes, quality of care, and patient satisfaction, while failure to consider language and culture can have serious adverse consequences for clinical care, including patient safety and healthcare access. A five-component model of cultural competency has been developed, and a growing literature details an array of normative cultural values, folk illnesses, parent beliefs/practices, and provider behaviors that can have a profound impact on pediatric care. Culturally sensitive interventions are being developed to lessen racial/ethnic health disparities.

SUMMARY

A goal for the pediatrician is to provide culturally competent healthcare by using trained medical interpreters with limited English-proficient families, being familiar with normative cultural values that affect the healthcare of commonly encountered racial/ethnic groups, and asking about folk illness beliefs and ethnomedical treatments.

Pattern of dipyrone exposure in Texas, 1998 to 2004

INTRODUCTION

Dipyrone is an analgesic and antipyretic agent. The purpose of this study was to describe the pattern of dipyrone exposures reported to poison centers.

METHODS

Human dipyrone exposures reported to 6 Texas poison centers from 1998 to 2004 were identified. Isolated and non-isolated cases were compared with respect to various factors.

RESULTS

When compared to the Census, dipyrone exposures were significantly more likely to have been reported from regions closer to the Mexican border (53% vs 9%). Of 81 dipyrone exposures, 52 (64%) were isolated and 29 (36%) were non-isolated. Most of the dipyrone exposures occurred at the patient's own residence (72/76 or 95%) and the patients were more likely to be female (54/81 or 67%). Although the majority of both types of dipyrone exposures were adults (47/78 or 60%), children, less than 6 years of age, accounted for a higher proportion of isolated exposures (33% vs 10%) while a higher proportion of non-isolated exposures involved older children (28% vs 8%). Twenty-two percent (11/51) of isolated cases were intentional while 59% (17/29) of non-isolated cases were intentional. Of those cases with a known medical outcome, the medical outcome was no adverse clinical effect for 76% (16/21) of isolated exposures and 42% (8/19) of non-isolated exposures. The specific adverse clinical effects reported for isolated exposures were primarily neurological (n = 6), gastrointestinal (n = 4), and dermal (n = 3). The most frequently reported treatment for isolated exposures was some form of decontamination (n = 11).

CONCLUSIONS

Isolated and non-isolated dipyrone exposures varied with respect to patient age, exposure reason, management site, medical outcome.

Imported compounded diet pill use among Brazilian women immigrants in the United States

In Brazil, compounded diet pills that combine amphetamines, benzodiazepines, antidepressants, diuretics and laxatives are often prescribed. In 2006, the Food and Drug Administration banned their sale in the United States (US) citing substantial safety concerns. This study evaluates the prevalence of, and factors associated with, use of these pills among Brazilian immigrant women aged 18-50. Pill use was assessed at one clinic and two churches using an anonymous survey (n = 307). While living in the US, 18% of clinic respondents and 9% of church respondents reported using these diet pills. Nearly two thirds of pill users reported adverse effects. In multivariate logistic regression analysis, being unmarried, college educated, dissatisfied with current weight, and advised by a US physician to lose weight were associated with greater odds of imported diet pill use. To enhance care of Brazilian immigrants, US physicians should become familiar with the health consequences of imported diet pills from Brazil.

Intramuscular Dipyrone versus Oral Ibuprofen or Nimesulide for Reduction of Fever in the Outpatient Setting

OBJECTIVE

To compare the effectiveness and rate of temperature reduction of three antipyretic medications in febrile children.

DESIGN

A single-dose, randomised, prospective, modified double-blind, parallel clinical trial.

SETTING

The paediatric emergency department of a university hospital that has 13 000 annual visits.

STUDY PARTICIPANTS

252 otherwise healthy children aged 6 months to 14 years with acute, intercurrent, febrile illness.

INTERVENTIONS

Enrolled children were assigned to receive a single dose of oral ibuprofen 10 mg/kg, oral nimesulide 2.5 mg/kg, or parenteral dipyrone 10 mg/kg.

MAIN OUTCOME MEASURES AND RESULTS

Axillary temperature was measured at the time of antipyretic administration and at 30, 45, 60 and 120 minutes thereafter. All three medications were effective in reducing the axillary temperature during the 2-hour testing period. The rates of axillary temperature change between the three medications were significantly different for the ibuprofen and dipyrone groups (p = 0.023). In addition, the axillary temperature in the dipyrone group was significantly lower than that in the ibuprofen group (p = 0.036) at 120 minutes. There was no significant difference in antipyretic effect between the nimesulide group and the other two groups during the testing period. Within each group the difference between initial temperature and the temperature at the end of the testing period was statistically significant (p = 0.036) for the dipyrone group only.

CONCLUSIONS

All three antipyretic medications were effective in reducing the axillary temperature in febrile children. Although administration of intramuscular dipyrone seemed to be more effective than ibuprofen, this relationship was not significant when nimesulide was considered. In addition, in view of its known side effects and the problems associated with intramuscular administration in children, the preference for orally administered nimesulide or ibuprofen over dipyrone in the setting of the emergency department seems more logical provided that the child accepts oral therapy.

Dipyrone and acetaminophen: correct dosing by parents?

CONTEXT AND OBJECTIVE

Several studies in developed countries have documented that a significant percentage of children are given inappropriate doses of acetaminophen and ibuprofen. The objective of this paper was to investigate parents' accuracy in giving dipyrone and acetaminophen to their children, in a poor region.

DESIGN AND SETTING

Cross-sectional study at the pediatric emergency department of Instituto Materno-Infantil Prof. Fernando Figueira, a teaching hospital in Pernambuco.

METHODS

The inclusion criteria were age between 3 and 36 months, main complaint of fever and at least one dose of dipyrone or acetaminophen given to the child during the 24 hours preceding their arrival at the emergency department. The mothers were asked for demographic information and about the antipyretic doses given, which were compared with the recommended dosage.

RESULTS

Among the 200 patients studied, 117 received dipyrone and 83 received acetaminophen. Overall, 75 % received an incorrect dose of antipyretic. Of the patients who received dipyrone, 105 (89.7%) were given an incorrect dose; 16 (15.2%) received too little dipyrone, and 89 (84.8%) received too much. Of the patients who received acetaminophen, 45 (54.2%) were given an incorrect dose; 38 (84.4%) received too little acetaminophen, and 7 (15.6%) received too much. There were no differences in maternal and child characteristics between the groups receiving correct and incorrect doses of medication, except for the type of medication (dipyrone versus acetaminophen).

CONCLUSIONS

Most of the children treated were given inappropriate doses, mainly dipyrone overdosing and acetaminophen underdosing.

Metamizole use among Hispanics in Miami: report of a survey conducted in a primary care setting

BACKGROUND

Metamizole (dipyrone) is a myelotoxic, nonsteroidal anti-inflammatory agent that has been banned from the US market since 1979. However, dipyrone may be purchased in some areas of the US. We conducted a survey in a primary care setting in Miami, Florida to determine the prevalence of metamizole possession and use among Hispanics living in this area.

METHODS

Participants consisted of 137 Hispanic outpatients interviewed consecutively during a primary care visit in the month of February 2005.

RESULTS

Metamizole was possessed by 28% of the surveyed population. The most common reasons for using dipyrone were pain (72%) and fever (24%). The vast majority of patients had purchased the medication in Latin America (95%), in most instances without a prescription (95%). Nineteen patients (13%) had used the medication during the previous year.

CONCLUSIONS

Metamizole is available to Latino immigrants who reside in the US, despite the FDA ban imposed in 1977.

Dipyrone-induced granulocytopenia: a case for awareness

Dipyrone, also known as metamizole, is an analgesic and antipyretic drug that was banned by the United States Food and Drug Administration because of its association with agranulocytosis. However, it is still produced and marketed in several countries in Central and South America as well as in Europe, Asia, and Africa. It can also be found in the United States, where illegal sales have been reported in California gift shops, markets, bakeries, and other retail establishments. Dipyrone is commonly found in the homes of families who are originally from areas where it is still lawfully marketed. We describe a patient who developed granulocytopenia and fever after taking dipyrone and discuss the available literature. Our aim is to raise awareness of this drug, which is commonly used outside the United States, and to call attention to its well-known and potentially lethal side effect.

Antipyretic efficacy and tolerability of oral ibuprofen, oral dipyrone and intramuscular dipyrone in children: a randomized controlled trial

CONTEXT AND OBJECTIVE

Dipyrone is a widely used over-the-counter antipyretic in Latin America, and elsewhere among Latin immigrants. Despite limited evidence, physicians often prescribe oral ibuprofen or intramuscular dipyrone as the most effective antipyretics. Our aim was to compare the antipyretic efficacy and tolerability of a single dose of oral ibuprofen, oral dipyrone or intramuscular dipyrone in febrile children.

DESIGN AND SETTING

Randomized, single-blind clinical trial, at San Bartolomé Mother-Child National Teaching Hospital, Lima, Peru.

METHODS

Children from six months to six years old with fever (rectal temperature: 38.3 to 39.8 degrees C) in the emergency ward between February and June 2003 were eligible. Seventy-five children were randomly assigned to receive a single dose of oral ibuprofen (10 mg/kg), oral dipyrone (15 mg/kg) or intramuscular dipyrone (15 mg/kg). The primary outcome was mean temperature reduction after 30, 45, 60, 90 and 120 minutes. Secondary outcomes were fever-associated symptoms and clinical adverse events.

RESULTS

Fever decreased by about 0.5 degrees C after 45 minutes and by about 1.0 degrees C after 120 minutes in all three groups. Mean temperatures were similar for the three groups at all times. There was a significant decrease in fever-associated symptoms for all groups. Six patients (four receiving oral dipyrone and two receiving ibuprofen) were withdrawn because of vomiting within 20 minutes after first dose of study medication. One patient assigned to oral ibuprofen presented transient urticaria.

CONCLUSIONS

Antipyretic efficacy and tolerability were similar for oral ibuprofen, oral dipyrone and intramuscular dipyrone. Oral antipyretics seem more appropriate for feverish children.

Dipyrone Overdose

BACKGROUND

Dipyrone is a pyrazolone derivative used as an analgesic and antipyretic. Agranulocytosis, dipyrone's most serious and potentially fatal adverse effect, has led to its withdrawal in several countries. However, agranulocytosis is subject to geographical variability, ratio with at risks ranging from 0.8-23.7. In many countries dipyrone is still widely used in adults and children and even as an over-the-counter (OTC) preparation. Information on the effects of dipyrone overdose is scanty.

OBJECTIVE

To determine the demographic and clinical characteristics of dipyrone overdose.

METHODS

Retrospective review of prospectively collected poison center data on acute exposure to dipyrone over a three-year period. The data were subjected to descriptive analysis. Mann-Whitney test and Chi-square analysis were performed where relevant.

RESULTS

A total of 243 records met the inclusion and exclusion criteria. Median age was 17y (4m-83y), median amount 5 g (250 mg-45 g), and median time to consultation was 2 h (5 min-48 h). Toxic events (49) occurred in 39 (16%) patients; 57% of these were gastrointestinal and all were mild. Time to consultation was longer in the symptomatic patients (4 h vs. 1.5 h, respectively, p=0.001) and in children (8 h vs. 3.5 h in adults). Suicidal patients ingested significantly larger amounts (8 g vs. 3.7 g, respectively, p=0.001), as did patients with gastrointestinal symptomatology (7.5 g vs. 5 g in asymptomatics, p=0.001). No agranulocytosis was reported.

DISCUSSION

Dipyrone overdose is associated with mild, mainly gastrointestinal toxicity; this was noted at a median dose of 7.5 g. Early gastrointestinal decontamination may have prevented toxicity. The suggested treatment includes gastrointestinal decontamination (if <1 h since ingestion) and supportive measures.