RESUMO
Despite the rising rates of resistance to dihydroartemisinin-piperaquine (DP), DP remains a first-line therapy for uncomplicated malaria in many parts of Cambodia. While DP is generally well tolerated as a 3-day DP (3DP) regimen, compressed 2-day DP (2DP) regimens were associated with treatment-limiting cardiac repolarization effects in a recent clinical trial. To better estimate the risks of piperaquine on QT interval prolongation, we pooled data from three randomized clinical trials conducted between 2010 and 2014 in northern Cambodia. A population pharmacokinetic model was developed to compare exposure-response relationships between the 2DP and 3DP regimens while accounting for differences in regimen and sample collection times between studies. A 2-compartment model with first-order absorption and elimination without covariates best fit the data. The linear slope-intercept model predicted a 0.05-ms QT prolongation per ng/ml of piperaquine (5 ms per 100 ng/ml) in this largely male population. Though the plasma half-life was similar in both regimens, peak and total piperaquine exposures were higher in those treated with the 2DP regimen. Furthermore, the correlation between the plasma piperaquine concentration and the QT interval prolongation was stronger in the population receiving the 2DP regimen. Neither the time since the previous meal nor the baseline serum magnesium or potassium levels had additive effects on QT interval prolongation. As electrocardiographic monitoring is often nonexistent in areas where malaria is endemic, 2DP regimens should be avoided and the 3DP regimen should be carefully considered in settings where viable alternative therapies exist. When DP is employed, the risk of cardiotoxicity can be mitigated by combining a 3-day regimen, enforcing a 3-h fast before and after administration, and avoiding the concomitant use of QT interval-prolonging medications. (This study used data from three clinical trials that are registered at ClinicalTrials.gov under identifiers NCT01280162, NCT01624337, and NCT01849640.).
Assuntos
Antimaláricos/efeitos adversos , Arritmias Cardíacas/induzido quimicamente , Artemisininas/farmacocinética , Malária Falciparum/tratamento farmacológico , Contração Miocárdica/efeitos dos fármacos , Quinolinas/farmacocinética , Antimaláricos/uso terapêutico , Artemisininas/efeitos adversos , Artemisininas/uso terapêutico , Camboja , Cardiotoxicidade , Quimioterapia Combinada , Feminino , Humanos , Malária Falciparum/parasitologia , Masculino , Contração Miocárdica/fisiologia , Plasmodium falciparum/efeitos dos fármacos , Quinolinas/sangue , Quinolinas/uso terapêuticoRESUMO
Deaths from drug overdose have become the leading cause of injury death in the United States, where the poison center system is available to provide real-time advice and collect data about a variety of poisonings. In 2012, emergency medical providers were confronted with new poisonings, such as bath salts (substituted cathinones) and Spice (synthetic cannabinoid drugs), as well as continued trends in established poisonings such as from prescription opioids. This article addresses current trends in opioid poisonings; new substances implicated in poisoning cases, including unit-dose laundry detergents, bath salts, Spice, and energy drinks; and the role of poison centers in public health emergencies such as the Fukushima radiation incident.
Assuntos
Intoxicação/epidemiologia , Adolescente , Adulto , Fatores Etários , Analgésicos Opioides/intoxicação , Criança , Pré-Escolar , Análise Custo-Benefício , Bases de Dados Factuais , Descontaminação/métodos , Detergentes/intoxicação , Serviços Médicos de Emergência/estatística & dados numéricos , Humanos , Centros de Controle de Intoxicações/economia , Centros de Controle de Intoxicações/estatística & dados numéricos , Intoxicação/economia , Intoxicação/etiologia , Intoxicação/mortalidade , Intoxicação/terapia , Estados Unidos/epidemiologia , Adulto JovemRESUMO
Dihydroartemisinin-piperaquine, the current first-line drug for uncomplicated malaria caused by Plasmodium falciparum and Plasmodium vivax in Cambodia, was previously shown to be of benefit as malaria chemoprophylaxis when administered as a monthly 3-day regimen. We sought to evaluate the protective efficacy of a compressed monthly 2-day treatment course in the Royal Cambodian Armed Forces. The safety and efficacy of a monthly 2-day dosing regimen of dihydroartemisinin-piperaquine were evaluated in a two-arm, randomized, double-blind, placebo-controlled cohort study with 2:1 treatment allocation. Healthy military volunteers in areas along the Thai-Cambodian border where there is a high risk of malaria were administered two consecutive daily doses of 180 mg dihydroartemisinin and 1,440 mg piperaquine within 30 min to 3 h of a meal once per month for a planned 4-month period with periodic electrocardiographic and pharmacokinetic assessment. The study was halted after only 6 weeks (69 of 231 projected volunteers enrolled) when four volunteers met a prespecified cardiac safety endpoint of QTcF (Fridericia's formula for correct QT interval) prolongation of >500 ms. The pharmacodynamic effect on the surface electrocardiogram (ECG) peaked approximately 4 h after piperaquine dosing and lasted 4 to 8 h. Unblinded review by the data safety monitoring board revealed mean QTcF prolongation of 46 ms over placebo at the maximum concentration of drug in serum (Cmax) on day 2. Given that dihydroartemisinin-piperaquine is one of the few remaining effective antimalarial agents in Cambodia, compressed 2-day treatment courses of dihydroartemisinin-piperaquine are best avoided until the clinical significance of these findings are more thoroughly evaluated. Because ECG monitoring is often unavailable in areas where malaria is endemic, repolarization risk could be mitigated by using conventional 3-day regimens, fasting, and avoidance of repeated dosing or coadministration with other QT-prolonging medications. (This study has been registered at ClinicalTrials.gov under registration no. NCT01624337.).
Assuntos
Antimaláricos/efeitos adversos , Antimaláricos/uso terapêutico , Arritmias Cardíacas/induzido quimicamente , Artemisininas/efeitos adversos , Artemisininas/uso terapêutico , Malária/tratamento farmacológico , Quinolinas/efeitos adversos , Quinolinas/uso terapêutico , Adulto , Antimaláricos/administração & dosagem , Artemisininas/administração & dosagem , Método Duplo-Cego , Feminino , Humanos , Masculino , Quinolinas/administração & dosagem , Adulto JovemRESUMO
PURPOSE: Adverse drug reactions, including overdose are a major cause of morbidity and mortality, yet clinical toxicology data is limited at the time of drug approval. This study was conducted to determine the quality of clinical toxicology data available for newly approved pharmaceuticals and time to labeling revisions. METHODS: The labeling data of 100 new molecular entities (NMEs) approved between 2005 and 2011 was systematically reviewed. Initial approval data and subsequent labeling revisions were evaluated. The type and quality of clinical toxicology data present at the time of approval as well as the time to any labeling revisions was recorded. The presence of black box warnings and Risk Evaluation and Mitigation Strategies (REMS) was noted. RESULTS: Of the NMEs reviewed, 27 had agent-specific toxicology data at approval. General recommendations for overdose management were made in 45 cases. Eight pharmaceuticals had toxicology updates during the study period. The average time to labeling revision was 27.4 months. Expanded adverse effects from case reports comprised 7/8 of the updates, and animal data was added in one case. Over a third of the NMEs had a black box warning or REMS status, suggesting potential for significant human toxicity. CONCLUSIONS: Our study suggests there is a paucity of clinical toxicology data at the time of drug approval, with a notable lag time between initial approval and labeling revisions. This lack of toxicology data limits the ability of providers to optimally care for poisoned patients.
Assuntos
Rotulagem de Medicamentos , Overdose de Drogas/terapia , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos , Intoxicação/terapia , Toxicologia , Animais , Aprovação de Drogas , Rotulagem de Medicamentos/normas , Fidelidade a Diretrizes , Guias como Assunto , Humanos , Farmacoepidemiologia , Estudos Retrospectivos , Medição de Risco , Fatores de Risco , Fatores de Tempo , Toxicologia/normasRESUMO
BACKGROUND: Severe malaria results in over a million deaths every year, most of them in children aged less than five years and living in sub-Saharan Africa. Injectable artesunate (AS) was recommended as initial treatment for severe malaria by WHO in 2006. The Walter Reed Army Institute of Research (WRAIR) has been developing a novel good manufacturing practice (GMP) injection of AS, which was approved by the US FDA for investigational drug use and distribution by the CDC. METHODS: Tolerability and pharmacokinetics of current GMP intravenous AS, as an anti-malarial agent, were evaluated after ascending multiple doses of 2, 4, and 8 mg/kg daily for three days with 2-minute infusion in 24 healthy subjects (divided into three groups) in the Phase 1 clinical trial study. RESULTS: Results showed that there were no dose-dependent increases in any adverse events. Drug concentrations showed no accumulation and no decline of the drug during the three days of treatment. After intravenous injection, parent drug rapidly declined and was converted to dihydroartemisinin (DHA) with overall mean elimination half-lives ranging 0.15-0.23 hr for AS and 1.23-1.63 hr for DHA, but the peak concentration (C(max)) of AS was much higher than that of DHA with a range of 3.08-3.78-folds. In addition, the AUC and C(max) values of AS and DHA were increased proportionally to the AS climbing multiple doses. DISCUSSION: The safety of injectable AS, even at the highest dose of 8 mg/kg increases the probability of therapeutic success of the drug even in patients with large variability of parasitaemia.
Assuntos
Antimaláricos/efeitos adversos , Antimaláricos/farmacocinética , Artemisininas/efeitos adversos , Artemisininas/farmacocinética , Adulto , África , Antimaláricos/administração & dosagem , Artemisininas/administração & dosagem , Artesunato , Resinas Compostas , Feminino , Voluntários Saudáveis , Humanos , Infusões Intravenosas , Masculino , Pessoa de Meia-Idade , Placebos/administração & dosagem , Estados Unidos , Adulto JovemRESUMO
The frequency and nature of elevation of liver-associated enzymes (LAE) are important safety endpoints in Phase 1 clinical trials of new anti-cocaine agents, yet very little information is available on the prevalence of abnormal LAE in cocaine experienced adults. The aim of this retrospective study was to investigate the alterations of liver-associated enzymes (LAE) aspartate- (AST) and alanine transaminase (ALT), alkaline phosphatase (ALP), gamma glutamyl transferase (GGT), and bilirubin in healthy "normal" (HN) and cocaine experienced (actively using cocaine preadmission (CE)) adults participating in long term inpatient clinical trials. We examined LAE values collected from 3 inpatient Phase 1 trials of anti-cocaine agents. Analysis of variance (ANOVA) was applied to determine the significance of various factors on LAE alterations. Gender, baseline BMI, treatment did not demonstrate significant group differences in LAE levels. CE study volunteers were found to have significantly higher AST and ALT values than HN volunteers (P<0.05) during their respective inpatient stays. 94.1% of the 17 subjects with abnormal LAE were CE, and 37.5% of these CE received placebo. In conclusion, despite normal baseline values, most subjects demonstrated an increase in the ALT level even on placebo. For CE subjects, differences (Delta ALT and Delta AST) between baseline and the maximum observed values were significantly higher than that observed for HN subjects. The potential to obscure important signals for hepatotoxicity during Phase 1 research may be higher in the CE study population.
Assuntos
Ensaios Clínicos Fase I como Assunto , Cocaína/antagonistas & inibidores , Enzimas/efeitos dos fármacos , Fígado/efeitos dos fármacos , Fígado/enzimologia , Adolescente , Adulto , Cocaína/metabolismo , Relação Dose-Resposta a Droga , Enzimas/análise , Enzimas/sangue , Feminino , Humanos , Pacientes Internados , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Estados UnidosRESUMO
A simple and sensitive HPLC-UV assay was developed for the measurement of iothalamate (IOT) in human serum and urine. Chromatographic separation was achieved using an embedded-carbamate-group bonded RP18 column and mobile phase consisting of 50 mM monobasic sodium phosphate and methanol (90:10, v/v) without the addition of ion-pair reagents. The assay demonstrated a high analytical reliability within the IOT concentration range of 1-150 microg/ml in serum and 25-1500 microg/ml in urine. The relative standard deviations (RSDs) for intra- and inter-day analysis were less than 5.1% in all cases. This method has been used for the evaluation of glomerular filtration rate (GFR) in subjects participating in a phase I clinical trial of a novel antimalarial medicine. The average baseline GFR was 100.41+/-19.99 ml/min/1.73 m(2) in 119 healthy volunteers. The assay may also allow the simultaneous measurements of p-aminohippuric acid (PAH), N-acetyl PAH (aPAH), and IOT with some modification. PAH, IOT, aPAH, and beta-hydroxyethyl-theophylline internal standard peaks appeared approximately at 2.5, 3.7, 5.9, and 11.8 min, respectively, in an isocratic run.
Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Taxa de Filtração Glomerular , Ácido Iotalâmico/análise , Humanos , Padrões de Referência , Reprodutibilidade dos Testes , Sensibilidade e EspecificidadeRESUMO
BACKGROUND: The American Association of Poison Control Centers (AAPCC; http://www.aapcc.org ) maintains the National Poison Data System (NPDS). Today, 60 of the nation's 61 US poison centers upload case data automatically. Most upload every 1- 60 minutes (median 11 minutes) to NPDS creating a real-time national exposure database and surveillance system. METHODOLOGY: We analyzed the case data tabulating specific indices from NPDS. The methodology was similar to that of previous years. Where changes were introduced, the differences are identified. Fatalities were reviewed by a team of 27 medical and clinical toxicologists and assigned to 1 of 6 categories according to Relative Contribution to Fatality (RCF). RESULTS: Over 4 million calls were captured by NPDS in 2006: 2,403,539 human exposure calls, 1,488,993 information requests, and 128,353 nonhuman exposure calls Substances involved most frequently in all human exposures were analgesics. The most common exposures in children less than age 6 were cosmetics/personal care products. NPDS documented 1,229 human fatalities. CONCLUSIONS: Poisoning continues to be a significant cause of morbidity and mortality in the US. NPDS represents a valuable national resource to collect and monitor US poisoning exposure cases. It offers one of the few real-time surveillance systems in existence, provides useful data and is a model for public health surveillance.
Assuntos
Exposição Ambiental/estatística & dados numéricos , Centros de Controle de Intoxicações/estatística & dados numéricos , Intoxicação/epidemiologia , Bases de Dados Factuais , Humanos , Intoxicação/mortalidade , Vigilância da População , Sociedades , Estados Unidos/epidemiologiaRESUMO
OBJECTIVES: This study was designed to evaluate effects of tadalafil, a phosphodiesterase-5 inhibitor used for the treatment of erectile dysfunction (ED), on the QT interval. BACKGROUND: Cardiovascular disease is common in men with ED. Men with cardiovascular disease and ED may have decreased cardiac repolarization reserve. METHODS: Effects of tadalafil (100 mg by mouth), ibutilide (0.002 mg/kg intravenously), and placebo on the QT interval in healthy men were compared (placebo and tadalafil [n = 90], with a subset [n = 61] receiving all treatments; mean age 30 years, range 18 to 53 years). Electrocardiographic sampling was done for two days before treatment and on treatment days. The QT was corrected for RR interval with five correction methods, including an individual correction (QTcI). Plasma concentrations of tadalafil were measured to evaluate concentration-QT effect relationships. RESULTS: At the time corresponding to maximum plasma concentration of tadalafil, the mean difference in the change in QTcI between tadalafil and placebo was 2.8 ms; tadalafil was equivalent to placebo (a priori, upper limit of 90% confidence interval < 10 ms [actual = 4.4 ms]; post hoc, upper limit of 95% confidence interval < 5 ms [actual = 4.8]). The active control, ibutilide, significantly increased QTcI by 6.9 and 8.9 ms compared with tadalafil and placebo, respectively. Similar statistical results were obtained with four additional QT correction methods. No subject had a QTcI > or = 450 ms or an increase in QTcI > or = 30 ms with any treatment. CONCLUSIONS: Based on the a priori statistical test of equivalence, placebo and high-dose tadalafil produced equivalent effects on the QT interval. This study reliably discerned 5- to 10-ms changes in corrected QT in the ibutilide active control group.
Assuntos
Antiarrítmicos/farmacologia , Carbolinas/efeitos adversos , Eletrocardiografia , Inibidores de Fosfodiesterase/efeitos adversos , Sulfonamidas/farmacologia , Função Ventricular/efeitos dos fármacos , Adolescente , Adulto , Carbolinas/farmacologia , Estudos de Casos e Controles , Eletrofisiologia , Disfunção Erétil/tratamento farmacológico , Humanos , Síndrome do QT Longo , Masculino , Pessoa de Meia-Idade , Inibidores de Fosfodiesterase/farmacologia , Placebos , Tadalafila , Fatores de TempoRESUMO
OBJECTIVE: To determine whether short-term human exposure to pyridostigmine bromide, diethyltoluamide, and permethrin, at rest or under stress, adversely affects short-term physical or neurocognitive performance. PARTICIPANTS AND METHODS: A multicenter, prospective, double-blind, placebo-controlled crossover trial exposing 64 volunteers to permethrin-impregnated uniforms, diethyltoluamide-containing skin cream, oral pyridostigmine, and corresponding placebos was performed. Each participant had 4 separate sessions, ensuring exposure to all treatments and placebos under both stress and rest conditions in random order. Outcomes Included physical performance (handgrip strength and duration, stair climbing, and pull-ups [males] or push-ups [females]), neurocognitive performance (computerized tests), and self-reported adverse effects. RESULTS: Permethrin was undetectable in the serum of all participants; pyridostigmine levels were higher Immediately after stress (41.6 ng/mL; 95% confidence Interval, 35.1-48.1 ng/mL) than rest (23.0 ng/mL; 95% confidence Interval, 19.2-26.9 ng/mL), whereas diethyltoluamide levels did not significantly differ by stress condition. Heart rate and systolic blood pressure increased significantly with stress compared with rest but did not vary with treatment vs placebo. Physical and neurocognitive outcome measures and self-reported adverse effects did not significantly differ by exposure group. CONCLUSION: Combined, correct use of pyridostigmine, diethyltoluamide, and permethrin is well tolerated and without evidence of short-term physical or neurocognitive impairment.
Assuntos
Inibidores da Colinesterase/efeitos adversos , DEET/efeitos adversos , Permetrina/efeitos adversos , Praguicidas/efeitos adversos , Esforço Físico/efeitos dos fármacos , Estresse Psicológico , Adulto , Pressão Sanguínea/efeitos dos fármacos , Proteínas Sanguíneas/análise , Inibidores da Colinesterase/administração & dosagem , Inibidores da Colinesterase/sangue , DEET/administração & dosagem , DEET/sangue , Exposição Ambiental , Feminino , Frequência Cardíaca/efeitos dos fármacos , Humanos , Masculino , Pessoa de Meia-Idade , Militares , Permetrina/administração & dosagem , Permetrina/sangue , Praguicidas/sangue , Esforço Físico/fisiologia , Estudos Prospectivos , Brometo de Piridostigmina/administração & dosagem , Brometo de Piridostigmina/efeitos adversos , Brometo de Piridostigmina/sangue , Análise de Regressão , Estados UnidosRESUMO
A rapid and highly sensitive gas chromatography-mass spectrometry (GC-MS) method for simultaneous determination of N,N-diethyl-m-toluamide (DEET) and permethrin with (2)H(10)-phenanthrene (98 atom %) as an internal standard and a separate external standard high-performance liquid chromatography (HPLC) method for pyridostigmine bromide (PB) determination in human plasma were developed and validated. The GC-MS method for DEET and permethrin quantification utilizes a one-step extraction with tert-butylmethylether. The HPLC method for PB quantification involves a solid-phase extraction and UV detection. The range of the analytical method for DEET and permethrin was 1 ng/mL to 100 ng/mL and for PB was 5 ng/mL to 100 ng/mL. Recovery from plasma proved to be more than 80%. The intraday precision ranged from 1.3% to 8% for DEET, from 2.1% to 11.4% for permethrin, and from 3.0% to 4.8% for PB. The interday precision was 3% for DEET, ranged from 5% to 9% for permethrin, and from 5% to 9% for PB. The accuracy for the limit of quantification was 92% +/- 8% relative standard deviation (RSD) for DEET, 112% +/- 11% RSD for permethrin, and 109% +/- 5% RSD for PB. All 3 compounds were stable in human plasma at -80 degrees C for at least 12 months and after 2 freeze-thaw cycles with RSD values ranging from 7.1% (DEET, 80 ng/mL) to 8.1% (DEET, 8 ng/mL), from 2.3% (permethrin, 80 ng/mL) to 11.6 % (permethrin, 8 ng/mL), and from 0.2% (PB, 80 ng/mL) to 3.6% (PB, 8 ng/mL). Both methods were successfully applied to pharmacokinetic/ pharmacodynamic studies of combined exposure of DEET (skin application), permethrin (treated uniforms), and PB (30 mg orally three times/day for four doses) in healthy volunteers (n = 81).
Assuntos
Cromatografia Líquida de Alta Pressão , DEET/sangue , Cromatografia Gasosa-Espectrometria de Massas/métodos , Repelentes de Insetos/sangue , Inseticidas/sangue , Permetrina/sangue , Brometo de Piridostigmina/sangue , DEET/farmacocinética , Estabilidade de Medicamentos , Humanos , Repelentes de Insetos/farmacocinética , Inseticidas/farmacocinética , Medicina Militar , Permetrina/farmacocinética , Brometo de Piridostigmina/farmacocinética , Reprodutibilidade dos TestesRESUMO
OBJECTIVES: This was a pilot study to determine (1) whether it is feasible to effectively blind human subjects to the presence of the insect repellents N,N-diethyl-m-toluamide (DEET) and permethrin; (2) whether DEET affects the absorption of permethrin; and (3) whether combat videotape viewing and mental arithmetic are stressful. METHODS: Ten volunteers were exposed to DEET, permethrin, and stress (1-hour combat videotape plus mental arithmetic) in a double-blind, randomized, placebo-controlled trial. Outcome measurements included hemodynamics, plasma DEET and permethrin levels, and questionnaires to assess blinding. RESULTS: Highly sensitive serologic assays readily detected DEET but not permethrin. Staff members and subjects were effectively blinded to both. The videotape-math combination was stressful by both self-report and hemodynamic measures. CONCLUSIONS: It is possible to blind subjects with respect to DEET and permethrin. Permethrin on clothing does not enter the bloodstream at appreciable levels. Combat videotapes and mental arithmetic can be stressful.
Assuntos
DEET/sangue , Repelentes de Insetos/sangue , Permetrina/sangue , Absorção Cutânea , Estresse Psicológico/fisiopatologia , Adulto , Estudos Cross-Over , Método Duplo-Cego , Feminino , Humanos , Modelos Lineares , Masculino , Projetos PilotoRESUMO
A 32-year-old male developed neuropsychiatric symptoms 2 weeks after starting mefloquine 250 mg/week for malaria prophylaxis. He continued to take the medication for the next 4 months. Initial symptoms included vivid dreams and anxiety, as well as balance problems. These symptoms persisted and progressed over the next 4 years to include vertigo, emotional lability, and poor short-term memory, which have greatly affected his personal and professional life. An extensive evaluation revealed objective evidence supporting a central vestibulopathy. These symptoms have been unresponsive to pharmacologic therapy and psychotherapy. A Naranjo assessment score of 6 was obtained for his initial symptoms, indicating a probable adverse drug reaction to mefloquine given the relationship between the clinical picture and drug exposure.
RESUMO
CONTEXT: Dietary supplements are widely used by military personnel and civilians for promotion of health. OBJECTIVE: The objective of this evidence-based review was to examine whether supplementation with l-arginine, in combination with caffeine and/or creatine, is safe and whether it enhances athletic performance or improves recovery from exhaustion for military personnel. DATA SOURCES: Information from clinical trials and adverse event reports were collected from 17 databases and 5 adverse event report portals. STUDY SELECTION: Studies and reports were included if they evaluated the safety and the putative outcomes of enhanced performance or improved recovery from exhaustion associated with the intake of arginine alone or in combination with caffeine and/or creatine in healthy adults aged 19 to 50 years. DATA EXTRACTION: Information related to population, intervention, comparator, and outcomes was abstracted. Of the 2687 articles screened, 62 articles meeting the inclusion criteria were analyzed. Strength of evidence was assessed in terms of risk of bias, consistency, directness, and precision. RESULTS: Most studies had few participants and suggested risk of bias that could negatively affect the results. l-Arginine supplementation provided little enhancement of athletic performance or improvements in recovery. Short-term supplementation with arginine may result in adverse gastrointestinal and cardiovascular effects. No information about the effects of arginine on the performance of military personnel was available. CONCLUSIONS: The available information does not support the use of l-arginine, either alone or in combination with caffeine, creatine, or both, to enhance athletic performance or improve recovery from exhaustion. Given the information gaps, an evidence-based review to assess the safety or effectiveness of multi-ingredient dietary supplements was not feasible, and therefore the development of a computational model-based approach to predict the safety of multi-ingredient dietary supplements is recommended.
Assuntos
Arginina/administração & dosagem , Arginina/efeitos adversos , Desempenho Atlético , Suplementos Nutricionais , Militares , Cafeína/administração & dosagem , Doenças Cardiovasculares/induzido quimicamente , Creatina/administração & dosagem , Suplementos Nutricionais/efeitos adversos , Gastroenteropatias/induzido quimicamente , HumanosRESUMO
Inhibition of drug metabolism is generally avoided but can be useful in limited circumstances, such as reducing the formation of toxic metabolites. Acetylation is a major pathway for drug elimination that can also convert substrates into toxic species, including carcinogens. Sulfamethoxazole, a widely used antibiotic, is metabolized via arylamine N-acetyltransferase 1. p-Aminosalicylate, used for antitubercular treatment, is also metabolized by N-acetyltransferase 1 and could potentially inhibit sulfamethoxazole metabolism. Human hepatocytes from 4 donors were incubated in vitro with sulfamethoxazole and paminosalicylate at clinically achievable concentrations. p-Aminosalicylate competitively reduced the acetylation of sulfamethoxazole in vitro by 61% to 83% at 200 microM. Four healthy volunteers were studied following doses of 500 mg sulfamethoxazole either alone or during administration of paminosalicylate (4 g ter in die). Plasma concentrations of paminosalicylate exceeded 100 microM. With each subject as his or her own control, p-aminosalicylate reduced by 5-fold the ratio of plasma concentrations of acetylsulfamethoxazole relative to parent drug (P < .001). Metabolic drug-drug interaction studies in vitro successfully predicted inhibition of acetylation via N-acetyltransferase 1 in vivo. Although no specific toxic species was investigated in this work, the potential was demonstrated for improving the therapeutic index of drugs that have toxic metabolites.
Assuntos
Arilamina N-Acetiltransferase/antagonistas & inibidores , Arilamina N-Acetiltransferase/farmacocinética , Sistemas de Liberação de Medicamentos/métodos , Sistemas de Liberação de Medicamentos/tendências , Isoenzimas/antagonistas & inibidores , Isoenzimas/farmacocinética , Sulfametoxazol/análogos & derivados , Adulto , Ácido Aminossalicílico/administração & dosagem , Ácido Aminossalicílico/sangue , Ácido Aminossalicílico/farmacocinética , Área Sob a Curva , Arilamina N-Acetiltransferase/efeitos dos fármacos , Células Cultivadas , Técnicas de Cultura/métodos , Relação Dose-Resposta a Droga , Esquema de Medicação , Feminino , Hepatócitos/efeitos dos fármacos , Hepatócitos/patologia , Humanos , Isoenzimas/efeitos dos fármacos , Masculino , Pessoa de Meia-Idade , Sulfametoxazol/administração & dosagem , Sulfametoxazol/antagonistas & inibidores , Sulfametoxazol/metabolismo , Sulfametoxazol/farmacocinéticaRESUMO
Cyclooxygenase-2 (COX-2) is up-regulated in stromal and inflammatory cells. The inducible COX-2 isoform is expressed during inflammation, in some cancers, and in brain tissue after global and focal ischemia. Tissue acidosis is a dominant factor in inflammation, and contributes to pain and hyperalgesia. Recently, compelling epidemiological and clinical evidence has documented the COX-independent effects of some COX-2 inhibitors (i.e., celecoxib, valdecoxib, and rofecoxib); among these effects are carbonic anhydrase (CA) inhibition. Carbonic anhydrases are zinc metalloenzymes expressed in various cell types, including those of the kidney, where they act as general acid-base catalysts. The kidneys are also known to express the highest concentration of COX-2 messenger ribonucleic acid. Celecoxib, like the prototypic CA inhibitor acetazolamide, is structurally characterized by an unsubstituted sulfonamide moiety. In the present study, we report that celecoxib exhibits the characteristics of a potent CA inhibitor, showing inhibitory human carbonic anhydrase II (hCAII) activity in the nanomolar range. Valdecoxib was relatively less potent. Rofecoxib, which lacks the unsubstituted sulfonamide moiety characteristic of CA inhibitors, showed no significant hCAII inhibitory activity. The current study corroborates our earlier report of structure-activity relationships as predictors of such metabolic events as hyperchloremia, acidosis, and changes in calcium and phosphate disposition; and clinical manifestations associated with CA inhibition reported with celecoxib. These data showing inhibition of hCAII by the unsubstituted sulfonamides celecoxib and valdecoxib, but not by rofecoxib, may have important implications for the elucidation of the mechanisms of action as well as the side effects associated with COX-2 inhibitors.
Assuntos
Anidrase Carbônica II/antagonistas & inibidores , Inibidores da Anidrase Carbônica/farmacologia , Inibidores de Ciclo-Oxigenase/farmacologia , Isoxazóis/farmacologia , Pirazóis/farmacologia , Sulfonamidas/farmacologia , Acetazolamida/farmacologia , Anti-Inflamatórios não Esteroides/farmacologia , Celecoxib , Relação Dose-Resposta a Droga , Humanos , Concentração Inibidora 50 , Isoxazóis/química , Pirazóis/química , Relação Estrutura-Atividade , Sulfonamidas/químicaRESUMO
BACKGROUND: This is the 31st Annual Report of the American Association of Poison Control Centers' (AAPCC) National Poison Data System (NPDS). As of January 1, 2013, 57 of the nation's poison centers (PCs) uploaded case data automatically to NPDS. The upload interval was 8.08 [7.10, 11.63] (median [25%, 75%]) minutes, creating a near real-time national exposure and information database and surveillance system. METHODOLOGY: We analyzed the case data tabulating specific indices from NPDS. The methodology was similar to that of previous years. Where changes were introduced, the differences are identified. Poison center (PC) cases with medical outcomes of death were evaluated by a team of 38 medical and clinical toxicologist reviewers using an ordinal scale of 1-6 to assess the Relative Contribution to Fatality (RCF) of the exposure to the death. RESULTS: In 2013, 3,060,122 closed encounters were logged by NPDS: 2,188,013 human exposures, 59,496 animal exposures, 806,347 information calls, 6,116 human-confirmed nonexposures, and 150 animal-confirmed nonexposures. Total encounters showed a 9.3% decline from 2012, while health care facility human exposure calls were essentially flat, decreasing by 0.1%.All information calls decreased 21.4% and health care facility (HCF) information calls decreased 8.5%, medication identification requests (drug ID) decreased 26.8%, and human exposures reported to US PCs decreased 3.8%. Human exposures with less serious outcomes have decreased 3.7% per year since 2008 while those with more serious outcomes (moderate, major or death) have increased by 4.7% per year since 2000. The top five substance classes most frequently involved in all human exposures were analgesics (11.5%), cosmetics/personal care products (7.7%), household cleaning substances (7.6%), sedatives/hypnotics/antipsychotics (5.9%), and antidepressants (4.2%). Sedative/hypnotics/antipsychotics exposures as a class increased most rapidly (2,559 calls/year) over the last 13 years for cases showing more serious outcomes. The top five most common exposures in children of 5 years or less were cosmetics/personal care products (13.8%), household cleaning substances (10.4%), analgesics (9.8%), foreign bodies/toys/miscellaneous (6.9%), and topical preparations (6.1%). Drug identification requests comprised 50.7% of all information calls. NPDS documented 2,477 human exposures resulting in death with 2,113 human fatalities judged related (RCF of 1, undoubtedly responsible; 2, probably responsible; or 3, contributory). CONCLUSIONS: These data support the continued value of PC expertise and need for specialized medical toxicology information to manage the more severe exposures, despite a decrease in calls involving less severe exposures. Unintentional and intentional exposures continue to be a significant cause of morbidity and mortality in the United States. The near real-time, always current status of NPDS represents a national public health resource to collect and monitor US exposure cases and information calls. The continuing mission of NPDS is to provide a nationwide infrastructure for public health surveillance for all types of exposures, public health event identification, resilience response and situational awareness tracking. NPDS is a model system for the nation and global public health.
Assuntos
Relatórios Anuais como Assunto , Bases de Dados Factuais , Serviços de Informação sobre Medicamentos , Overdose de Drogas , Centros de Controle de Intoxicações , Antídotos/uso terapêutico , Overdose de Drogas/diagnóstico , Overdose de Drogas/mortalidade , Overdose de Drogas/terapia , Humanos , Medição de Risco , Fatores de Risco , Resultado do Tratamento , Estados Unidos/epidemiologiaRESUMO
This Department of Defense-sponsored evidence-based review evaluates the safety and putative outcomes of enhancement of athletic performance or improved recovery from exhaustion in studies involving beta-alanine alone or in combination with other ingredients. Beta-alanine intervention studies and review articles were collected from 13 databases, and safety information was collected from adverse event reporting portals. Due to the lack of systematic studies involving military populations, all the available literature was assessed with a subgroup analysis of studies on athletes to determine if beta-alanine would be suitable for the military. Available literature provided only limited evidence concerning the benefits of beta-alanine use, and a majority of the studies were not designed to address safety. Overall, the strength of evidence in terms of the potential for risk of bias in the quality of the available literature, consistency, directness, and precision did not support the use of beta-alanine by military personnel. The strength of evidence for a causal relation between beta-alanine and paresthesia was moderate.
Assuntos
Suplementos Nutricionais , Militares , beta-Alanina/administração & dosagem , Desempenho Atlético/fisiologia , Medicina Baseada em Evidências , Humanos , Estados UnidosRESUMO
BACKGROUND: This is the 30(th) Annual Report of the American Association of Poison Control Centers' (AAPCC) National Poison Data System (NPDS). As of July 1, 2012, 57 of the nation's poison centers (PCs) uploaded case data automatically to NPDS. The upload interval was 7.58 [6.30, 11.22] (median [25%, 75%]) min, creating a near real-time national exposure and information database and surveillance system. METHODOLOGY: We analyzed the case data tabulating specific indices from NPDS. The methodology was similar to that of previous years. Where changes were introduced, the differences are identified. Poison center cases with medical outcomes of death were evaluated by a team of 34 medical and clinical toxicologist reviewers using an ordinal scale of 1-6 to assess the Relative Contribution to Fatality (RCF) of the exposure to the death. RESULTS: In 2012, 3,373,025 closed encounters were logged by NPDS: 2,275,141 human exposures, 66,440 animal exposures, 1,025,547 information calls, 5,679 human confirmed nonexposures, and 218 animal confirmed nonexposures. Total encounters showed a 6.9% decline from 2011, while healthcare facility (HCF) exposure calls increased by 1.2%. All information calls decreased by 14.8% and HCF information calls decreased by 1.7%, medication identification requests (Drug ID) decreased by 22.0%, and human exposures reported to US PCs decreased by 2.5%. Human exposures with less serious outcomes have decreased by 3.7% per year since 2008, while those with more serious outcomes (moderate, major, or death) have increased by 4.6% per year since 2000. The top five substance classes most frequently involved in all human exposures were analgesics (11.6%), cosmetics/personal care products (7.9%), household cleaning substances (7.2%), sedatives/hypnotics/antipsychotics (6.1%), and foreign bodies/toys/miscellaneous (4.1%). Analgesic exposures as a class increased the most rapidly (8,780 calls/year) over the last 12 years. The top five most common exposures in children aged 5 years or less were cosmetics/ personal care products (13.9%), analgesics (9.9%), household cleaning substances (9.7%), foreign bodies/toys/ miscellaneous (7.0%), and topical preparations (6.3%). Drug identification requests comprised 54.4% of all information calls. NPDS documented 2,937 human exposures resulting in death with 2,576 human fatalities judged related (RCF of 1-Undoubtedly responsible, 2-Probably responsible, or 3-Contributory). CONCLUSIONS: These data support the continued value of PC expertise and need for specialized medical toxicology information to manage the more severe exposures, despite a decrease in calls involving less severe exposures. Unintentional and intentional exposures continue to be a significant cause of morbidity and mortality in the US. The near real-time, always current status of NPDS represents a national public health resource to collect and monitor US exposure cases and information calls. The continuing mission of NPDS is to provide a nationwide infrastructure for public health surveillance for all types of exposures, public health event identification, resilience response, and situational awareness tracking. NPDS is a model system for the nation and global public health.
Assuntos
Exposição Ambiental/análise , Sistemas de Informação/organização & administração , Centros de Controle de Intoxicações/organização & administração , Animais , Bases de Dados Factuais , Humanos , Vigilância da População , Estados UnidosRESUMO
OBJECTIVES: Atomoxetine has been considered as an agonist replacement therapy for cocaine. We investigated the safety of the interaction of atomoxetine with cocaine and also whether cognitive function was affected by atomoxetine during short-term administration. METHODS: In a double-blind placebo-controlled inpatient study of 20 cocaine-dependent volunteers, participants received atomoxetine 80 mg daily followed by 100 mg daily for 5 days each. On the fourth and fifth day at each dose, cocaine (20 and 40 mg) was infused intravenously in sequential daily sessions. RESULTS: Preinfusion mean systolic pressures showed a small but statistically significant difference between placebo and both doses of atomoxetine. Preinfusion mean diastolic pressures were significant between placebo and atomoxetine 80 mg only. The diastolic pressure response to 40 mg cocaine was statistically significant only between the 80- and 100-mg atomoxetine doses. All electrocardiogram parameters were unchanged. Visual Analog Scale (VAS) scores for "bad effect" in the atomoxetine group were significantly higher at baseline, then declined, and for "likely to use" declined with atomoxetine treatment. On the Addiction Research Center Inventory, the atomoxetine group scored significantly lower on amphetamine, euphoria, and energy subscales (P < 0.0001). Other VAS descriptors, Brief Substance Craving Scale, Profile of Moods State, and Brief Psychiatric Rating Scale showed no differences. Atomoxetine did not affect cocaine pharmacokinetics. In tests of working memory, sustained attention, cognitive flexibility, and decision-making, atomoxetine improved performance on the visual n-back task. There were no differences in any pharmacokinetic parameters for cocaine with atomoxetine. CONCLUSIONS: Atomoxetine was tolerated safely by all participants. Certain cognitive improvements and a dampening effect on VAS scores after cocaine were observed, but should be weighed against small but significant differences in hemodynamic responses after atomoxetine.