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Wang Y, Wang Y, Zhao Q, Cong W, Wang N, Zhao K, Liu J, Liu X, Zhao G, Lambert H, Huang M, Wang H, Chen Y, Jiang Q. Impact of low-level exposure to antibiotics on bile acid homeostasis in adults: Implication for human safety thresholds. ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY 2024; 279:116451. [PMID: 38759535 PMCID: PMC11170111 DOI: 10.1016/j.ecoenv.2024.116451] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/18/2024] [Revised: 04/25/2024] [Accepted: 05/09/2024] [Indexed: 05/19/2024]
Abstract
Bile acid homeostasis is critical to human health. Low-level exposure to antibiotics has been suggested to potentially disrupt bile acid homeostasis by affecting gut microbiota, but relevant data are still lacking in humans, especially for the level below human safety threshold. We conducted a cross-sectional study in 4247 Chinese adults by measuring 34 parent antibiotics and their metabolites from six common categories (i.e., tetracyclines, qinolones, macrolides, sulfonamides, phenicols, and lincosamides) and ten representative bile acids in fasting morning urine using liquid chromatography coupled to mass spectrometry. Daily exposure dose of antibiotics was estimated from urinary concentrations of parent antibiotics and their metabolites. Urinary bile acids and their ratios were used to reflect bile acid homeostasis. The estimated daily exposure doses (EDED) of five antibiotic categories with a high detection frequency (i.e., tetracyclines, qinolones, macrolides, sulfonamides, and phenicols) were significantly associated with urinary concentrations of bile acids and decreased bile acid ratios in all adults and the subset of 3898 adults with a cumulative ratio of antibiotic EDED to human safety threshold of less than one. Compared to a negative detection of antibiotics, the lowest EDED quartiles of five antibiotic categories and four individual antibiotics with a high detection frequency (i.e., ciprofloxacin, ofloxacin, trimethoprim, and florfenicol) in the adults with a positive detection of antibiotics had a decrease of bile acid ratio between 6.6% and 76.6%. Except for macrolides (1.2×102 ng/kg/day), the medians of the lowest EDED quartile of antibiotic categories and individual antibiotics ranged from 0.32 ng/kg/day to 10 ng/kg/day, which were well below human safety thresholds. These results suggested that low-level antibiotic exposure could disrupt bile acid homeostasis in adults and existing human safety thresholds may be inadequate in safeguarding against the potential adverse health effects of low-level exposure to antibiotics.
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Affiliation(s)
- Yuanping Wang
- Key Laboratory of Public Health Safety of Ministry of Education/School of Public Health, Fudan University, Shanghai 200032, China
| | - Yi Wang
- Key Laboratory of Public Health Safety of Ministry of Education/School of Public Health, Fudan University, Shanghai 200032, China
| | - Qi Zhao
- Key Laboratory of Public Health Safety of Ministry of Education/School of Public Health, Fudan University, Shanghai 200032, China
| | - Wenjuan Cong
- Department of Population Health Sciences, Bristol Medical School, University of Bristol, Bristol BS8 2PS, UK
| | - Na Wang
- The People's Hospital of Pingyang, Pingyang County, Wenzhou, Zhejiang Province 325400, China
| | - Ke Zhao
- Key Laboratory of Public Health Safety of Ministry of Education/School of Public Health, Fudan University, Shanghai 200032, China
| | - Jiaqi Liu
- Key Laboratory of Public Health Safety of Ministry of Education/School of Public Health, Fudan University, Shanghai 200032, China
| | - Xiaohua Liu
- Minhang District Center for Disease Control and Prevention, Minhang District, Shanghai 201101, China
| | - Genming Zhao
- Key Laboratory of Public Health Safety of Ministry of Education/School of Public Health, Fudan University, Shanghai 200032, China
| | - Helen Lambert
- Department of Population Health Sciences, Bristol Medical School, University of Bristol, Bristol BS8 2PS, UK
| | - Min Huang
- The People's Hospital of Pingyang, Pingyang County, Wenzhou, Zhejiang Province 325400, China.
| | - Hexing Wang
- Key Laboratory of Public Health Safety of Ministry of Education/School of Public Health, Fudan University, Shanghai 200032, China.
| | - Yue Chen
- School of Epidemiology and Public Health, Faculty of Medicine, University of Ottawa, Ottawa, Ontario K1G 5Z3, Canada
| | - Qingwu Jiang
- Key Laboratory of Public Health Safety of Ministry of Education/School of Public Health, Fudan University, Shanghai 200032, China
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Wang S, Xing L, Sun X, Li Z, Ding T, Wang J, Peng J, Ma H, Lin T, Yang Q. Metabolites and metabolic pathway analysis of sulfadimidine in carp (Cyprinus carpio) based on UHPLC-Q-orbitrap HRMS. ENVIRONMENTAL RESEARCH 2024; 252:118967. [PMID: 38642643 DOI: 10.1016/j.envres.2024.118967] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/15/2024] [Revised: 04/04/2024] [Accepted: 04/17/2024] [Indexed: 04/22/2024]
Abstract
Sulfadimidine (SM2) is an N-substituted derivative of p-aminobenzenesulfonyl structure. This study aimed to analyze the metabolism of SM2 in carp (Cyprinus carpio). The carps were fed with SM2 at a dose of 200 mg/(kg · bw) and then killed. The blood, muscle, liver, kidney, gill, other guts, and carp aquaculture water samples were collected. The UHPLC-Q-Exactive Plus Orbitrap-MS was adopted for determining the metabolites of SM2 in the aforementioned samples. Twelve metabolites, which were divided into metabolites in vivo and metabolites in vitro, were identified using Compound Discoverer software. The metabolic pathways in vivo of SM2 in carp included acetylation, hydroxylation, glucoside conjugation, glycine conjugation, carboxylation, glucuronide conjugation, reduction, and methylation. The metabolic pathways in vitro included oxidation and acetylation. This study clarified the metabolites and metabolic pathways of SM2 in carp and provided a reference for further pharmacodynamic evaluation and use in aquaculture.
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Affiliation(s)
- Shuwen Wang
- Yellow Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, Key Laboratory of Testing and Evaluation for Aquatic Product Safety and Quality, Ministry of Agriculture and Rural Affairs, Qingdao, China.
| | - Lihong Xing
- Yellow Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, Key Laboratory of Testing and Evaluation for Aquatic Product Safety and Quality, Ministry of Agriculture and Rural Affairs, Qingdao, China
| | - Xiaojie Sun
- Yellow Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, Key Laboratory of Testing and Evaluation for Aquatic Product Safety and Quality, Ministry of Agriculture and Rural Affairs, Qingdao, China
| | - Zhaoxin Li
- Yellow Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, Key Laboratory of Testing and Evaluation for Aquatic Product Safety and Quality, Ministry of Agriculture and Rural Affairs, Qingdao, China.
| | - Tao Ding
- Yellow Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, Key Laboratory of Testing and Evaluation for Aquatic Product Safety and Quality, Ministry of Agriculture and Rural Affairs, Qingdao, China
| | - Jiyao Wang
- Yellow Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, Key Laboratory of Testing and Evaluation for Aquatic Product Safety and Quality, Ministry of Agriculture and Rural Affairs, Qingdao, China
| | - Jixing Peng
- Yellow Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, Key Laboratory of Testing and Evaluation for Aquatic Product Safety and Quality, Ministry of Agriculture and Rural Affairs, Qingdao, China
| | - Haijian Ma
- ANPEL Laboratory Technologies, Shanghai, China
| | - Ting Lin
- ANPEL Laboratory Technologies, Shanghai, China
| | - Qingli Yang
- College of Food Science and Engineering, Qingdao Agricultural University, Qingdao, China
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3
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Zhu M, Wang Z, Chen J, Xie H, Zhao H, Yuan X. Bioaccumulation, Biotransformation, and Multicompartmental Toxicokinetic Model of Antibiotics in Sea Cucumber ( Apostichopus japonicus). ENVIRONMENTAL SCIENCE & TECHNOLOGY 2020; 54:13175-13185. [PMID: 32985863 DOI: 10.1021/acs.est.0c04421] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Extensive application of antibiotics leads to their ubiquitous occurrence in coastal aquatic environments. However, it remains largely unknown whether antibiotics can be bioaccumulated and biotransformed in major mariculture organisms such as sea cucumbers and toxicokinetic models for Echinodermata are lacking. In this study, laboratory exposure experiments on juvenile sea cucumber (Apostichopus japonicus) were performed for seven antibiotics (sulfadiazine, sulfamethoxazole, trimethoprim, enrofloxacin, ofloxacin, clarithromycin, and azithromycin). Field sea cucumber and surrounding seawater samples were also analyzed. Results show that the sea cucumbers tend to accumulate high concentrations of the antibiotics with kinetic bioconcentration factors (BCFs) up to 1719.7 L·kg-1 for ofloxacin. The BCFs determined in the laboratory agree well with those estimated from the field measurements. Seven biotransformation products (BTPs) of the antibiotics were identified, four of which were not reported previously in aquatic organisms. The BTPs were mainly found in the digestive tract, indicating its high capacity in the biotransformation. A multicompartmental toxicokinetic model based on the principles of passive diffusion was developed, which can successfully predict time-course concentrations of the antibiotics in different compartments of the juvenile sea cucumbers. The findings may offer a scientific basis for assessing health risks and guiding healthy mariculture of sea cucumbers.
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Affiliation(s)
- Minghua Zhu
- Key Laboratory of Industrial Ecology and Environmental Engineering (Ministry of Education), School of Environmental Science and Technology, Dalian University of Technology, Dalian 116024, China
| | - Zhongyu Wang
- Key Laboratory of Industrial Ecology and Environmental Engineering (Ministry of Education), School of Environmental Science and Technology, Dalian University of Technology, Dalian 116024, China
| | - Jingwen Chen
- Key Laboratory of Industrial Ecology and Environmental Engineering (Ministry of Education), School of Environmental Science and Technology, Dalian University of Technology, Dalian 116024, China
| | - Huaijun Xie
- Key Laboratory of Industrial Ecology and Environmental Engineering (Ministry of Education), School of Environmental Science and Technology, Dalian University of Technology, Dalian 116024, China
| | - Hongxia Zhao
- Key Laboratory of Industrial Ecology and Environmental Engineering (Ministry of Education), School of Environmental Science and Technology, Dalian University of Technology, Dalian 116024, China
| | - Xiutang Yuan
- National Marine Environmental Monitoring Center, Ministry of Ecology and Environment, Dalian 116023, China
- Key Laboratory of Coastal Biology and Bioresource Utilization, Yantai Institute of Coastal Zone Research, Chinese Academy of Sciences, Yantai 264003, China
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Xiao C, Chen F, Liu Z, Zhang Y, Chen C, Chen H, Zhou H, Gao Z. Ultrasound-Assisted Extraction Combined with HPLC-UV for Fast Determination of Sulfamethazine and Its N4-Acetyl Metabolite in Plasma and Phosphate Buffer. ANAL LETT 2012. [DOI: 10.1080/00032719.2012.677976] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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Kaufmann A. Determination of the elemental composition of trace analytes in complex matrices using exact masses of product ions and corresponding neutral losses. RAPID COMMUNICATIONS IN MASS SPECTROMETRY : RCM 2007; 21:2003-13. [PMID: 17546657 DOI: 10.1002/rcm.3035] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/15/2023]
Abstract
The emergence of time-of-flight (TOF) and hybrid quadrupole/time-of-flight (Q-TOF) mass spectrometers has offered new possibilities for determining the elemental composition of analytes present at trace levels. The mass accuracy provided by these instruments is currently in the range of 2-5 m m/z units, permitting the determination of the elemental composition of small molecules. The orthogonal information of relative isotopic abundances (RIAs) is used to reduce the number of elemental compositions that are possible, based on consideration of exact masses. Elimination of additional possible compositions has been reported when the analyte is fragmented and its resulting product ions and corresponding neutral losses are carefully analyzed. Published algorithms reduce the number of proposed precursor ions by deleting each precursor candidate which cannot be explained by summing any combination of postulated product ion and corresponding neutral loss elemental composition candidates. An extension of such algorithms is described in this paper. This approach compares not only the precursor ion with the different fragments, but tests the possible descent of any ion from all other recorded ions. This extended algorithm has been tested by processing published data. Algorithms analyzing product ion spectra can be used for real-life data. However, there is a risk that an ion which originates from the mobile phase or from a co-eluting matrix compound can be mathematically correlated to the investigated precursor ion. Such an incorrect correlation can lead to the deletion of a correct elemental composition. This is an important issue if TOF rather than Q-TOF instruments are used. Therefore, ultra-performance liquid chromatography (UPLC) and a peak deconvolution algorithm were used to generate and process TOF chromatograms in order to minimize the number of ions which are not related to the analyte precursor ion. The combined use of chromatographic deconvolution and product ion spectra has been tested and is critically discussed.
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Affiliation(s)
- Anton Kaufmann
- Official Food Control Authority of the Canton of Zurich (Kantonales Labor Zürich), P.O. Box, CH-8030 Zürich, Switzerland.
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Vree TB, Beneken Kolmer WJ, Hekster YA, Shimoda M, Ono M, Miura T. Pharmacokinetics and acetylation of sulfa-2-monomethoxine in humans. Biopharm Drug Dispos 1992; 13:55-68. [PMID: 1554877 DOI: 10.1002/bdd.2510130105] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
In humans sulfa-2-monomethoxine (S) is metabolized by N4-acetylation (39.9 +/- 8.0 per cent). After an oral dose, S is eliminated biphasically (t1/2, 5.2 +/- 1.6 h and 13.2 +/- 3.4 h) which is similar in both fast and slow acetylators. The metabolite N4-acetylsulfa-2-monomethoxine (N4) is eliminated monophasically (t1/2, 30.0 +/- 5.7 h). The intrinsic mean residence time (MRT) of N4 is 33.5 +/- 8.8 h. The mean total body clearance of S is 11.6 +/- 2.7 ml min-1, and the Vdss is 12.3 +/- 1.01. The renal clearance of S during the first day was twice as high as on the following days for two of the six volunteers (8 vs 4 ml min-1). The renal clearance of N4 during the first day, for four out of the six volunteers, was twice as high as on the following days (8 vs 4 ml min-1). The protein binding of S is 95 per cent and that of its conjugate N4 98 per cent. Approximately 80 per cent of the oral dose of S is excreted in the urine as parent drug (41.0 +/- 6.2 per cent) and as N4 acetyl conjugate (39.9 +/- 8.0 per cent).
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Affiliation(s)
- T B Vree
- Department of Clinical Pharmacy, Academic Hospital Nijmegen Sint-Radboud, The Netherlands
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Vree TB, Beneken Kolmer EW, Hekster YA. Pharmacokinetics, N1-glucuronidation and N4-acetylation of sulfamethomidine in humans. PHARMACEUTISCH WEEKBLAD. SCIENTIFIC EDITION 1991; 13:198-206. [PMID: 1749708 DOI: 10.1007/bf01988875] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Sulfamethomidine metabolism was studied in 6 volunteers. In humans, only N1-glucuronidation and N4-acetylation take place, leading to the final double conjugate N4-acetylsulfamethomidine N1-glucuronide. The N1-glucuronides were directly measured by high pressure liquid chromatography. Fast and slow acetylators show a similar half-life for sulfamethomidine (26 +/- 6 h) and its conjugates sulfamethomidine (26 +/- 6 h) and N4-acetylsulfamethomidine (36 +/- 16 h). Approximately 50-60% of the oral dose of sulfamethomidine is excreted in the urine, leaving 40-50% for excretion into bile and faeces. The main metabolite of sulfamethomidine is its N1-glucuronide, which accounts for 36 +/- 7% of the dose, followed by N4-acetylsulfamethomidine (16 +/- 8%). N1-glucuronidation results in a 75% decrease in protein binding of sulfamethomidine. N4-acetylsulfamethomidine and its N1-glucuronide showed the same high protein binding of 99%. The renal clearance of N4-acetylsulfamethomidine is 7.9 +/- 2.2 ml/min and approximately 20 times as high as that of the parent drug (0.46 +/- 0.16 ml/min). Total body clearance of sulfamethomidine is 4.5 +/- 0.9 ml/min and the volume of distribution in steady state 10.6 +/- 1.7 1. No measurable plasma concentrations of the N1-glucuronides from sulfamethomidine are found in plasma. This may be explained by renal glucuronidation after active tubular reabsorption.
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Affiliation(s)
- T B Vree
- Department of Clinical Pharmacy, University Hospital Nijmegen Sint Radboud, The Netherlands
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8
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Yuan ZH, Fung KF. Pharmacokinetics of sulfadimidine and its N4-acetyl metabolite in healthy and diseased rabbits infected with Pasteurella multocida. J Vet Pharmacol Ther 1990; 13:192-7. [PMID: 2384910 DOI: 10.1111/j.1365-2885.1990.tb00768.x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
The pharmacokinetics of sulfadimidine (SDM) and its N4-acetyl metabolite (N4SDM) were investigated after intravenous bolus injection of a single dose (200 mg/kg) of SDM in normal and diseased New Zealand white rabbits. The apparent distribution volume at steady state, total body clearance and elimination half-life of SDM in normal animals were 0.7 +/- 0.3 l/kg, 0.57 +/- 0.24 l/kg/h and 1.6 +/- 1.3 h, respectively. Of the administered dose, 62.1% was metabolized by N4-acetylation, and 12.7 +/- 1.1 and 2.8 +/- 1.8% of the dose was excreted as free drug by the kidney and gastrointestinal tract, respectively. The 'apparent' formation and elimination half-lives of N4SDM were 0.6 +/- 0.4 and 2.2 +/- 1.1 h, respectively. The metabolite was eliminated mainly by excretion through the kidney. There was no significant effect of acute pasteurellosis on the pharmacokinetics of either SDM or N4SDM in rabbits.
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Affiliation(s)
- Z H Yuan
- Department of Veterinary Medicine, South China Agricultural University, Guangzhou, China
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9
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Vree TB, Beneken Kolmer EW, Martea M, Bosch R, Hekster YA, Shimoda M. Pharmacokinetics, N1-glucuronidation and N4-acetylation of sulfadimethoxine in man. PHARMACEUTISCH WEEKBLAD. SCIENTIFIC EDITION 1990; 12:51-9. [PMID: 2336339 DOI: 10.1007/bf01970146] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Sulfadimethoxine is metabolized by O-dealkylation, N4-acetylation and N1-glucuronidation. In man, only N1-glucuronidation and N4-acetylation takes place, leading to the final double conjugate N4-acetylsulfadimethoxine-N1-glucuronide. The N1-glucuronides are directly measured by high pressure liquid chromatography. When N4-acetylsulfadimethoxine is administered as parent drug, 30% of the dose is N1-glucuronidated and excreted. Fast acetylators show a shorter half-life for sulfadimethoxine than slow acetylators (27.8 +/- 4.2 h versus 36.3 +/- 5.4 h; P = 0.013), similarly the half-life of the N4-acetyl conjugate is also shorter in fast acetylators (41.3 +/- 5.2 h versus 53.5 +/- 8.5 h, P = 0.036). No measurable plasma concentrations of the N1-glucuronides from sulfadimethoxine are found in plasma. N1-glucuronidation results in a 75% decrease in protein binding of sulfadimethoxine. N4-acetylsulfadimethoxine and its N1-glucuronide showed the same high protein binding of 99%. Approximately 50-60% of the oral dose of sulfadimethoxine is excreted in the urine, leaving 40-50% for excretion into bile and faeces.
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Affiliation(s)
- T B Vree
- Department of Clinical Pharmacy, University Hospital Nijmegen, The Netherlands
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10
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Vree TB, Vree JB, De Jonge PA, Plaum MJ, Verwey CP, Hekster YA, Shimoda M, Nouws JF. Lack of oxidative pathways in the metabolism of sulphisomidine by the turtle Pseudemys scripta elegans. J Vet Pharmacol Ther 1989; 12:459-62. [PMID: 2614863 DOI: 10.1111/j.1365-2885.1989.tb00699.x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Affiliation(s)
- T B Vree
- Department of Clinical Pharmacy, Sint Radboud Hospital, Geert, Nijmegen
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Younan W, Nouws JF, Homeid AM, Vree TB, Degen M. Pharmacokinetics and metabolism of sulphadimidine in the camel. J Vet Pharmacol Ther 1989; 12:327-9. [PMID: 2810483 DOI: 10.1111/j.1365-2885.1989.tb00679.x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Affiliation(s)
- W Younan
- Department of Veterinary Pharmacology and Toxicology, Faculty of Veterinary Science, University of Khartoum, North Sudan
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12
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Nouws JF, Mevius D, Vree TB, Degen M. Pharmacokinetics and renal clearance of sulphadimidine, sulphamerazine and sulphadiazine and their N4-acetyl and hydroxy metabolites in pigs. Vet Q 1989; 11:78-86. [PMID: 2741297 DOI: 10.1080/01652176.1989.9694203] [Citation(s) in RCA: 30] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023] Open
Abstract
The effect of molecular structure on the drug disposition and protein binding in plasma, the urinary recovery, and the renal clearance of sulphamerazine (SMR), sulphadiazine (SDZ), and sulphadimidine (SDM) and their N4-acetyl and hydroxy derivatives were studied in pigs. Following IV administration of SDM, SMR and SDZ, their mean elimination half-lives were 12.4 h, 4.3 h and 4.9 h respectively. The plasma concentrations of parent sulphonamide were higher than those of the metabolites, and ran parallel. The acetylated derivatives were the main metabolites; traces of 6-hydroxymethylsulphamerazine and 4-hydroxysulphadiazine were detected in plasma. The urine recovery data showed that in pigs acetylation is the major elimination pathway of SDM, SMR and SDZ; hydroxylation became more important in case of SMR (6-hydroxymethyl and 4-hydroxy derivatives) and SDZ (4-hydroxy derivatives) than in SDM. In pigs methyl substitution of the pyrimidine side chain decreased the renal clearance of the parent drug and made the parent compound less accessible for hydroxylation. Acetylation and hydroxylation speeded up drug elimination, because their renal clearance values were higher than those of the parent drug.
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Affiliation(s)
- J F Nouws
- RVV-District 6, Nijmegen, The Netherlands
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Abstract
Overdose of carbamazepine (CBZ) can be fatal. We report the case of a patient with near-lethal toxicity due to delayed absorption of drug. A 36-year-old woman was admitted with coma, hypotension, and unusual movements. Carbamazepine (CBZ) level several hours later was 36 mg/L. Gastric lavage revealed no pill fragments, and activated charcoal was administered. CBZ level initially fell, reaching 28 mg/L 36 h after admission. Blood level then rose sharply, reaching 54 mg/L 64 h after admission. The pattern of rise suggested renewed absorption of drug. Vigorous cathartics were given, and further doses of charcoal were administered. Three hours after onset of diarrhea, roving eye movements occurred. Two hours later she grimaced to pain. Eight hours after the onset of diarrhea, she was awake. In CBZ overdose, activated charcoal therapy coupled with aggressive intestinal purging helps prevent continued absorption of drug, late exacerbation of symptoms, and potentially fatal outcome.
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Affiliation(s)
- M Sethna
- Department of Neurology, New York Hospital-Cornell University Medical College, New York
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Affiliation(s)
- D A Evans
- Riyadh Armed Forces Hospital, Saudi Arabia
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