The Experts below are selected from a list of 264 Experts worldwide ranked by ideXlab platform
â Venâncio - One of the best experts on this subject based on the ideXlab platform.
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opioid false positivity in urine drug screening Levomepromazine cross reactivity
Psychiatry and Clinical Psychopharmacology, 2017Co-Authors: N Rodriguessilva, â VenâncioAbstract:ABSTRACTUrine drug screening false-positives are reported for several drugs, which may lead to clinical misdiagnosis and have negative consequences for the patient on personal and social grounds, if not identified. False-positives for opiates are rare, but we report a case where high-dose Levomepromazine was very likely involved.
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P-82 - Please, believe me! opioids false-positive in urine drug screening: Levomepromazine cross-reactivity
European Psychiatry, 2012Co-Authors: N. Rodrigues-silva, â VenâncioAbstract:Introduction Urine drug screen false-positives can have quite negative consequences to the patient, on personal and social levels and lead to clinical misdiagnosis. Objectives To report a case of opioid false-positive in urine drug screen (TOX/See BIO-RAD) in a patient medicated with Levomepromazine and discuss the implications of our findings. Aims To stress the importance of excluding cross-reactivity induced by drugs in patients presenting with psychiatric symptoms. Methods Report of a case and overview of the literature available in MEDLINE. Results A 24-year old man was involuntarily committed to our psyhiatric inpatient unit with a diagnosis of manic episode. A rapid urine drug toxicology screen was positive for cannabinoids. In the past he consumed heroin and cocaine. At present, he reports using cannabinoids only. He started risperidone, lorazepam and Levomepromazine. In the next days, Levomepromazine dosage was increased. During hospitalization there was a suspicion that the patient was consuming drugs. A urine drug screen was performed on day 7 and it was positive for cannabinoids and opioids, which the patient contested. The test was repeated five times, every 2 days, and remained positive. After that a different test, a direct identification test in blood, was performed and it was negative for opioids. Levomepromazine was discontinued. One day after the urine drug screen was repeated and was negative for opioids. This is the first report suggesting opioids cross-reactivity in urine drug screen induced by Levomepromazine. Conclusions Levomepromazine or it's interactions with other drugs may cause false-positives in urine drug screen.
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p 82 please believe me opioids false positive in urine drug screening Levomepromazine cross reactivity
European Psychiatry, 2012Co-Authors: N Rodriguessilva, â VenâncioAbstract:Introduction Urine drug screen false-positives can have quite negative consequences to the patient, on personal and social levels and lead to clinical misdiagnosis. Objectives To report a case of opioid false-positive in urine drug screen (TOX/See BIO-RAD) in a patient medicated with Levomepromazine and discuss the implications of our findings. Aims To stress the importance of excluding cross-reactivity induced by drugs in patients presenting with psychiatric symptoms. Methods Report of a case and overview of the literature available in MEDLINE. Results A 24-year old man was involuntarily committed to our psyhiatric inpatient unit with a diagnosis of manic episode. A rapid urine drug toxicology screen was positive for cannabinoids. In the past he consumed heroin and cocaine. At present, he reports using cannabinoids only. He started risperidone, lorazepam and Levomepromazine. In the next days, Levomepromazine dosage was increased. During hospitalization there was a suspicion that the patient was consuming drugs. A urine drug screen was performed on day 7 and it was positive for cannabinoids and opioids, which the patient contested. The test was repeated five times, every 2 days, and remained positive. After that a different test, a direct identification test in blood, was performed and it was negative for opioids. Levomepromazine was discontinued. One day after the urine drug screen was repeated and was negative for opioids. This is the first report suggesting opioids cross-reactivity in urine drug screen induced by Levomepromazine. Conclusions Levomepromazine or it's interactions with other drugs may cause false-positives in urine drug screen.
N Rodriguessilva - One of the best experts on this subject based on the ideXlab platform.
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opioid false positivity in urine drug screening Levomepromazine cross reactivity
Psychiatry and Clinical Psychopharmacology, 2017Co-Authors: N Rodriguessilva, â VenâncioAbstract:ABSTRACTUrine drug screening false-positives are reported for several drugs, which may lead to clinical misdiagnosis and have negative consequences for the patient on personal and social grounds, if not identified. False-positives for opiates are rare, but we report a case where high-dose Levomepromazine was very likely involved.
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opioid false positive in urine drug screening due to Levomepromazine cross
2015Co-Authors: N Rodriguessilva, Rua Da Conceicao FernandesAbstract:In urine screening, false-positives are often reported for several drugs. This may lead to clinical misdiagnosis and has negative consequences for the patient on personal and social grounds, if they are not identified. False-positives for opiates are rare, but we report a case where a high-dose of Levomepromazine was involved.
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p 82 please believe me opioids false positive in urine drug screening Levomepromazine cross reactivity
European Psychiatry, 2012Co-Authors: N Rodriguessilva, â VenâncioAbstract:Introduction Urine drug screen false-positives can have quite negative consequences to the patient, on personal and social levels and lead to clinical misdiagnosis. Objectives To report a case of opioid false-positive in urine drug screen (TOX/See BIO-RAD) in a patient medicated with Levomepromazine and discuss the implications of our findings. Aims To stress the importance of excluding cross-reactivity induced by drugs in patients presenting with psychiatric symptoms. Methods Report of a case and overview of the literature available in MEDLINE. Results A 24-year old man was involuntarily committed to our psyhiatric inpatient unit with a diagnosis of manic episode. A rapid urine drug toxicology screen was positive for cannabinoids. In the past he consumed heroin and cocaine. At present, he reports using cannabinoids only. He started risperidone, lorazepam and Levomepromazine. In the next days, Levomepromazine dosage was increased. During hospitalization there was a suspicion that the patient was consuming drugs. A urine drug screen was performed on day 7 and it was positive for cannabinoids and opioids, which the patient contested. The test was repeated five times, every 2 days, and remained positive. After that a different test, a direct identification test in blood, was performed and it was negative for opioids. Levomepromazine was discontinued. One day after the urine drug screen was repeated and was negative for opioids. This is the first report suggesting opioids cross-reactivity in urine drug screen induced by Levomepromazine. Conclusions Levomepromazine or it's interactions with other drugs may cause false-positives in urine drug screen.
Maria Augusta Raggi - One of the best experts on this subject based on the ideXlab platform.
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determination of selected phenothiazines in human plasma by solid phase extraction and liquid chromatography with coulometric detection
Analytica Chimica Acta, 2008Co-Authors: Maria Addolorata Saracino, Mario Amore, Elena Baioni, Carmine Petio, Maria Augusta RaggiAbstract:Abstract A new analytical method, based on liquid chromatography with coulometric detection, has been developed and applied to the determination of selected phenothiazines (chlorpromazine, promazine, fluphenazine and Levomepromazine) in human plasma. The drugs were separated on a Discovery pentafluorophenylpropyl column, using a mobile phase composed of acetonitrile (32%) and a pH 1.9 phosphate buffer (68%). Promethazine was used as the internal standard. Detection was carried out at an oxidation potential of +0.500 V. A novel clean-up procedure was developed by means of solid-phase extraction, using cyanopropyl cartridges, which gave good extraction yield for all the analytes, with absolute recovery values higher than 91.0%. The detector response was linear over a plasma concentration range of 0.5–250.0 ng mL −1 for chlorpromazine, promazine and Levomepromazine and of 0.2–4.0 ng mL −1 for fluphenazine. Precision results, expressed by the intra-day and the inter-day relative standard deviation values, were good, being lower than 3.9%. Accuracy data were satisfactory as well. The method has been successfully applied to the analysis of drug plasma levels of psychiatric patients undergoing therapy with selected phenothiazines.
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simultaneous determination of the antipsychotic drugs Levomepromazine and clozapine and their main metabolites in human plasma by a hplc uv method with solid phase extraction
Journal of Chromatography B, 2007Co-Authors: Laura Mercolini, Francesca Bugamelli, Ernst Kenndler, Giancarlo Boncompagni, Livia Franchini, Maria Augusta RaggiAbstract:A HPLC method with UV detection has been developed for the simultaneous determination of Levomepromazine, clozapine and their main metabolites: N-desmethyl-Levomepromazine, Levomepromazine sulphoxide, O-desmethyl-Levomepromazine, N-desmethylclozapine and clozapine N-oxide. The analytes were separated on a C8 reversed-phase column using a mobile phase composed of acetonitrile and a pH 2.0, 34 mM phosphate buffer containing 0.3% triethylamine (29:71, v/v). Loxapine was used as the internal standard. A reliable biological sample pre-treatment procedure by means of solid-phase extraction on C1 cartridges was implemented, which allows to obtain good extraction yields (>91%) for all analytes and appropriate sample purification from endogenous interference. The method was validated in terms of extraction yield, precision and accuracy. These assays gave RSD% values for precision always lower than 4.9% and mean accuracy values higher than 92%. The method is suitable for the therapeutic drug monitoring (TDM) of patients undergoing polypharmacy with Levomepromazine and clozapine.
Joanna Karpinska - One of the best experts on this subject based on the ideXlab platform.
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studies on photodegradation of Levomepromazine and olanzapine under simulated environmental conditions
Photochemical and Photobiological Sciences, 2012Co-Authors: Joanna Karpinska, Aneta Sokol, Anna Bernatowicz, Aneta Szulecka, Urszula KotowskaAbstract:The present study discusses the influence of sunlight on the photostability of Levomepromazine (LV) and olanzapine (OLA) hydrochlorides in river water. Four samples of water from different rivers were used in the research. In their course, it turned out that Levomepromazine easily underwent photooxidation under simulated environmental conditions, resulting in the generation of its sulphoxide. Olanzapine, on the other hand, appeared to be more resistant to sunlight, as its photodecomposition proceeded slowly, and only one product of its decomposition was detected spectrophotometrically during the process. The photodegradation was analyzed in detail using principal component analysis (PCA) and multivariate curve resolution alternating least squares (MCR-ALS) chemometric methods, and the outcomes verified by HPLC and GC-MS analysis. It can be stated that the rates of the observed processes heavily depended on the chemical composition of the fresh water used in the experiments.
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an application of uv derivative spectrophotometry and bivariate calibration algorithm for study of photostability of Levomepromazine hydrochloride
Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy, 2008Co-Authors: Joanna Karpinska, Aneta Sokol, Marta SkoczylasAbstract:Abstract Derivative spectrophotometry and bivariate calibration algorithm were used for study of run of photooxidation of Levomepromazine hydrochloride (LV). The actual concentrations of LV and its main degradation product Levomepromazine sulphoxide (LV-SO) were calculated using data provided by applied methods. The direct reading of absorbance values at 302 nm and 334 nm were employed for quantification of LV and LV-SO, respectively, in the case of bivariate method. The derivative spectrophotometric method is based on transformation of zero-order spectra into first derivative. The values of first derivative at 334 nm were used for quantification of LV while at 278 nm for assay of LV-SO. The obtained quantitative data were applied for investigation of kinetics of photodegradation of LV.
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simultaneous determination of Levomepromazine hydrochloride and its sulfoxide by uv derivative spectrophotometry and bivariate calibration method
Analytical Letters, 2006Co-Authors: Joanna Karpinska, Aneta Wiszowata, Marta SkoczylasAbstract:Abstract Two spectrophotometric methods are proposed for the simultaneous quantification of Levomepromazine hydrochloride (LV) and its main degradation product Levomepromazine sulfoxide (LV‐SO). One of them is based on the first order derivative spectra generated by the Savitzky‐Golay algorithm (third‐order polynomial degree, Δλ=10 nm). Determination of Levomepromazine hydrochloride and its sulfoxide was realized by measurements of amplitudes of derivative spectra at 332 nm and 278 nm, respectively. The Beer law was obeyed in the concentration range 1.5–50 µg/mL for LV and 2.5–50 µg/mL for LV‐SO. The second of the proposed methods utilized the bivariate calibration algorithm. The determination was performed at 302 nm for Levomepromazine and at 334 nm for sulfoxide. The elaborated methods allowed determination of LV in the concentration range 1.0–25 µg/mL while LV‐SO was determined in the concentration range 2.0–50 µg/mL.
Marta Skoczylas - One of the best experts on this subject based on the ideXlab platform.
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an application of uv derivative spectrophotometry and bivariate calibration algorithm for study of photostability of Levomepromazine hydrochloride
Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy, 2008Co-Authors: Joanna Karpinska, Aneta Sokol, Marta SkoczylasAbstract:Abstract Derivative spectrophotometry and bivariate calibration algorithm were used for study of run of photooxidation of Levomepromazine hydrochloride (LV). The actual concentrations of LV and its main degradation product Levomepromazine sulphoxide (LV-SO) were calculated using data provided by applied methods. The direct reading of absorbance values at 302 nm and 334 nm were employed for quantification of LV and LV-SO, respectively, in the case of bivariate method. The derivative spectrophotometric method is based on transformation of zero-order spectra into first derivative. The values of first derivative at 334 nm were used for quantification of LV while at 278 nm for assay of LV-SO. The obtained quantitative data were applied for investigation of kinetics of photodegradation of LV.
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simultaneous determination of Levomepromazine hydrochloride and its sulfoxide by uv derivative spectrophotometry and bivariate calibration method
Analytical Letters, 2006Co-Authors: Joanna Karpinska, Aneta Wiszowata, Marta SkoczylasAbstract:Abstract Two spectrophotometric methods are proposed for the simultaneous quantification of Levomepromazine hydrochloride (LV) and its main degradation product Levomepromazine sulfoxide (LV‐SO). One of them is based on the first order derivative spectra generated by the Savitzky‐Golay algorithm (third‐order polynomial degree, Δλ=10 nm). Determination of Levomepromazine hydrochloride and its sulfoxide was realized by measurements of amplitudes of derivative spectra at 332 nm and 278 nm, respectively. The Beer law was obeyed in the concentration range 1.5–50 µg/mL for LV and 2.5–50 µg/mL for LV‐SO. The second of the proposed methods utilized the bivariate calibration algorithm. The determination was performed at 302 nm for Levomepromazine and at 334 nm for sulfoxide. The elaborated methods allowed determination of LV in the concentration range 1.0–25 µg/mL while LV‐SO was determined in the concentration range 2.0–50 µg/mL.