FeS2 nanosheets-luminol-O2 chemiluminescence method for determination of venlafaxine hydrochloride, imipramine hydrochloride, and cefazolin sodium.

This study introduces a novel chemiluminescence (CL) approach utilizing FeS2 nanosheets (NSs) catalyzed luminol-O2 CL reaction for the measurement of three pharmaceuticals, namely venlafaxine hydrochloride (VFX), imipramine hydrochloride (IPM), and cefazolin sodium (CEF). The CL method involved the phenomenon of quenching induced by the pharmaceuticals in the CL reaction. To achieve the most quenching efficacy of the pharmaceuticals in the CL reaction, the concentrations of reactants comprising luminol, NaOH, and FeS2 NSs were optimized accordingly. The calibration curves demonstrated exceptional linearity within the concentration range spanning from 4.00 × 10-7 to 1.00 × 10-3 mol L-1, 1.00 × 10-7 to 1.00 × 10-4 mol L-1, and 4.00 × 10-6 to 2.00 × 10-4 mol L-1 with detection limits (3σ) of 3.54 × 10-7, 1.08 × 10-8, and 2.63 × 10-6 mol L-1 for VFX, IPM, and CEF, respectively. This study synthesized FeS2 NSs using a facile hydrothermal approach, and then the synthesized FeS2 NSs were subjected to a comprehensive characterization using a range of spectroscopic methods. The proposed CL method was effective in measuring the aforementioned pharmaceuticals in pharmaceutical formulations as well as different water samples. The mechanism of the CL system has been elucidated.

PBPK modeling to predict the pharmacokinetics of venlafaxine and its active metabolite in different CYP2D6 genotypes and drug-drug interactions with clarithromycin and paroxetine.

Venlafaxine, a serotonin-norepinephrine reuptake inhibitor (SNRI), is indicated for the treatment of major depressive disorder, social anxiety disorder, generalized anxiety disorder, and panic disorder. Venlafaxine is metabolized to the active metabolite desvenlafaxine mainly by CYP2D6. Genetic polymorphism of CYP2D6 and coadministration with other medications can significantly affect the pharmacokinetics and/or pharmacodynamics of venlafaxine and its active metabolite. This study aimed to establish the PBPK models of venlafaxine and its active metabolite related to CYP2D6 genetic polymorphism and to predict drug-drug interactions (DDIs) with clarithromycin and paroxetine in different CYP2D6 genotypes. Clinical pharmacogenomic data for venlafaxine and desvenlafaxine were collected to build the PBPK model. Physicochemical and absorption, distribution, metabolism, and excretion (ADME) characteristics of respective compounds were obtained from previously reported data, predicted by the PK-Sim® software, or optimized to capture the plasma concentration-time profiles. Model evaluation was performed by comparing the predicted pharmacokinetic parameters and plasma concentration-time profiles to the observed data. Predicted plasma concentration-time profiles of venlafaxine and its active metabolite were visually similar to the observed profiles and all predicted AUC and Cmax values for respective compounds were included in the twofold error range of observed values in non-genotyped populations and different CYP2D6 genotypes. When clarithromycin or clarithromycin plus paroxetine was concomitantly administered, predicted plasma concentration-time profiles of venlafaxine properly captured the observed profiles in two different CYP2D6 genotypes and all predicted DDI ratios for AUC and Cmax were included within the acceptance range. Consequently, the present model successfully captured the pharmacokinetic alterations of venlafaxine and its active metabolite according to CYP2D6 genetic polymorphism as well as the DDIs between venlafaxine and two CYP inhibitors. The present model can be used to predict the pharmacokinetics of venlafaxine and its active metabolite considering different races, ages, coadministered drugs, and CYP2D6 activity of individuals and it can contribute to individualized pharmacotherapy of venlafaxine.

Análisis retrospectivo de las hipoglucemias inducidas por venlafaxina en pacientes con sobredosis / Retrospective analysis of venlafaxine-induced hypoglycemia in patients with overdose

Introducción: Estudios recientes en intoxicaciones por venlafaxina (VLF) relacionan la presencia de hipoglucemia con la dosis. Nuestro objetivo fue analizar las características clínicas de los pacientes que presentaron hipoglucemia inducida por sobredosis de VLF.Pacientes y métodosEstudio retrospectivo realizado en las Islas Baleares (2020-2023). Como criterios de inclusión se tomaron en cuenta las concentraciones séricas de VLF + ortodesmetilvenlafaxina (O-VLF) > 800 ng/mL. Se compararon las características de los pacientes con y sin hipoglucemia.ResultadosSe incluyeron 21 pacientes, ocho (38,1%) con hipoglucemia. No se hallaron diferencias en las dosis referidas en ambos grupos. Las concentraciones máximas de VLF + O-VLF (ng/mL) fueron 9.783 (4.459-17.976) en sujetos con hipoglucemia y 1.413 (930-1.769) en aquellos sin esta enfermedad (p<0,0001). La presencia de hipoglucemia se asoció con: menor edad y nivel de conciencia; y mayor frecuencia de tentativas suicidas, convulsiones, midriasis, taquicardia y síndrome serotoninérgico, soporte respiratorio invasivo, sueroterapia e ingreso en la Unidad de Cuidados Intensivos (UCI) (p < 0,05).ConclusionesLa detección de hipoglucemia en individuos intoxicados por VLF es un marcador fácilmente disponible para sospechar la gravedad del paciente. En cualquier caso, las concentraciones séricas, cuando se disponen, permiten confirmar la intoxicación. (AU)

Introduction: Recent publications relate the presence of hypoglycemia in venlafaxine (VLX) poisoning depending on the dose. Our aim was to analyze the clinical characteristics of patients who presented hypoglycemia induced by VLF overdose.Patients and methodsRetrospective study carried out in the Balearic Islands (2020–2023). Inclusion criteria: serum concentrations of VLX + O-desmethyl-venlafaxine (O-VLX)>800 ng/mL. The characteristics of patients with and without hypoglycemia were compared.ResultsTwenty-one patients were included, 8 (38.1%) with hypoglycemia. No differences were found in the doses referred to in both groups. Peak concentrations of VLX + O-VLX (ng/mL) were 9,783 [4,459–17,976] in patients with hypoglycemia and 1,413 [930–1,719] in patients without hypoglycemia (p<0.0001). The presence of hypoglycemia was associated with: lower age and level of consciousness; and higher frequency of suicide attempts, seizures, mydriasis, tachycardia and serotonin syndrome, invasive respiratory support, fluid therapy and ICU admission (p<0.05).ConclusionsThe detection of hypoglycemia in a VLX overdose case is a readily available marker to suspect the severity of the patient. In any case, serum concentrations when available allow us to confirm intoxication. (AU)

Comparative Study of the Effects of Duloxetine and Venlafaxine on Acute Symptomatic Taxane-induced Neuropathy in Breast Cancer Patients: A Randomized Clinical Trial.

Introduction: Chemotherapeutic agents have the potential to induce neurotoxicity, resulting in a range of symptoms, including mild paresthesia, neuropathic pain, pronounced ataxia, and significant impairment. Taxane-induced neuropathy (TIN) is a prevalent adverse effect and a significant constraint of Taxane-based chemotherapy protocols in treating breast cancer. In this current study, we aim to compare the effects of Venlafaxine and Duloxetine in taxane-induced Neuropathy as well as the quality of life, Depression, and Anxiety in Breast cancer Patients. Methods: The present study investigated breast cancer patients who experienced acute neuropathic pain after receiving paclitaxel treatment, a chemotherapeutic agent. The participants were allocated randomly into two groups, one receiving Venlafaxine and the other receiving Duloxetine. The participants underwent assessments for anxiety, depression, pain, neuropathy, quality of life, and neuropathic pain through the administration of questionnaires at the commencement of the study and after ten weeks following the intervention. Results: Both groups exhibited decreased neuropathic pain, with the venlafaxine group significantly reducing McGill's pain score. Although, the result is not suggestive of a difference between venlafaxine and duloxetine impact on any variables scores. Conclusion: Duloxetine and Venlafaxine effectively treat neuropathic symptoms such as paraesthesia, tingling, and itching. Venlafaxine is also beneficial for relieving pain associated with neuropathy.This trial was retrospectively registered on 1.1.2023 at irct.ir (trial registration ID: IRCT20220115053723N1). URL: https://www.irct.ir/trial/62540/pdf.

Efficacy and safety of venlafaxine hydrochloride combined with tandospirone citrate for patients with vascular depression accompanied by somatic symptoms: An open-labeled randomized control trial.

AIMS: To explore the pharmacological treatment of vascular depression (VaDep) and whether the blood levels of neurotransmitters can reflect the VaDep severity. METHODS: VaDep patients with somatic symptoms were enrolled and randomly received venlafaxine + tandospirone (Combined Group) or venlafaxine (Monotherapy Group). The treatment efficacy was assessed by Hamilton Depression Scale (HAMD), Hamilton Anxiety Scale (HAMA), and Patient Health Questionnaire-15 (PHQ-15). The levels of blood monoamine neurotransmitters were measured by enzyme-linked immunosorbent assay. RESULTS: Both groups reported a progressive decrease in HAMD, HAMA, and PHQ-15 scores to below the baseline after the respective treatment. Compared with the Monotherapy Group, the Combined Group reported a significant decrease in HAMD score at week 2 and markedly lower HAMA and PHQ-15 scores at weeks 1, 2, 4, and 8. Both groups showed a decrease in the levels of blood monoamine neurotransmitters at weeks 4 and 8 when compared with the baseline. A strong positive association was evident between the plasma 5-HT levels and the HAMD score. CONCLUSION: The combined therapy rapidly acts on VaDep comorbid with anxiety and somatic symptoms and significantly alleviates the anxiety and somatic symptoms. The plasma levels of 5-HT may serve as potential objective candidates in evaluating VaDep severity and the efficacy of the undertaken treatment regimen.

Physiologically Based Pharmacokinetic Modeling to Unravel the Drug-gene Interactions of Venlafaxine: Based on Activity Score-dependent Metabolism by CYP2D6 and CYP2C19 Polymorphisms.

BACKGROUND: Venlafaxine (VEN) is a commonly utilized medication for alleviating depression and anxiety disorders. The presence of genetic polymorphisms gives rise to considerable variations in plasma concentrations across different phenotypes. This divergence in phenotypic responses leads to notable differences in both the efficacy and tolerance of the drug. PURPOSE: A physiologically based pharmacokinetic (PBPK) model for VEN and its metabolite O-desmethylvenlafaxine (ODV) to predict the impact of CYP2D6 and CYP2C19 gene polymorphisms on VEN pharmacokinetics (PK). METHODS: The parent-metabolite PBPK models for VEN and ODV were developed using PK-Sim® and MoBi®. Leveraging prior research, derived and implemented CYP2D6 and CYP2C19 activity score (AS)-dependent metabolism to simulate exposure in the drug-gene interactions (DGIs) scenarios. The model's performance was evaluated by comparing predicted and observed values of plasma concentration-time (PCT) curves and PK parameters values. RESULTS: In the base models, 91.1%, 94.8%, and 94.6% of the predicted plasma concentrations for VEN, ODV, and VEN + ODV, respectively, fell within a twofold error range of the corresponding observed concentrations. For DGI scenarios, these values were 81.4% and 85% for VEN and ODV, respectively. Comparing CYP2D6 AS = 2 (normal metabolizers, NM) populations to AS = 0 (poor metabolizers, PM), 0.25, 0.5, 0.75, 1.0 (intermediate metabolizers, IM), 1.25, 1.5 (NM), and 3.0 (ultrarapid metabolizers, UM) populations in CYP2C19 AS = 2.0 group, the predicted DGI AUC0-96 h ratios for VEN were 3.65, 3.09, 2.60, 2.18, 1.84, 1.56, 1.34, 0.61, and for ODV, they were 0.17, 0.35, 0.51, 0.64, 0.75, 0.83, 0.90, 1.11, and the results were similar in other CYP2C19 groups. It should be noted that PK differences in CYP2C19 phenotypes were not similar across different CYP2D6 groups. CONCLUSIONS: In clinical practice, the impact of genotyping on the in vivo disposition process of VEN should be considered to ensure the safety and efficacy of treatment.

A rational study of transduction mechanisms of different materials for all solid contact-ISEs.

The new era of solid contact ion selective electrodes (SC-ISEs) miniaturized design has received an extensive amount of concern. Because it eliminated the requirement for ongoing internal solution composition optimization and created a two-phase system with stronger detection limitations. Herein, the determination of venlafaxine HCl is based on a comparison study between different ion- to electron transduction materials (such as; multiwalled carbon nanotubes (MWCNTs), polyaniline (PANi), and ferrocene) and illustrating their mechanisms in their applied sensors. Their different electrochemical features (such as bulk resistance (Rb**), double-layer capacitance (Cdl), geometric capacitance (Cg), and specific capacitance (Cp)) were evaluated and discussed by using the Electrochemical Impedance Spectroscopy (EIS), Chronopotentiometry (CP), and Cyclic Voltammetry (CV) experiments. The results indicated that each transducer's influence on the proposed sensor's electrochemical characteristics is determined by their unique chemical and physical properties. The electrochemical features vary for different solid contact materials used in transduction mechanisms. The results confirm that the MWCNT sensor revealed the best electrochemical behavior with the potentiometric response of a near-Nernestian slope of 56.1 ± 0.8 mV/decade with detection limits of 3.8 × 10-6 mol/L (r2 = 0.999) and a low potential drift (∆E/∆t) of 34.6 µV/s. Also, the selectivity study was performed in the presence of different interfering species either in single or complex matrices. This demonstrates excellent selectivity, stability, conductivity, and reliability as a VEN-TPB ion pair sensor for accurately measuring VEN in its various formulations. The proposed method was compared to HPLC reported technique and confirmed no significant difference between them. So, the proposed sensors fulfill their solutions' demand features for VEN appraisal.

Multiplexed quantification of venlafaxine and metabolites in human plasma by liquid chromatography-tandem mass spectrometry.

BACKGROUND: Venlafaxine (VEN) and its O-demethylated metabolite, O-desmethylvenlafaxine (ODV), are commonly prescribed serotonin-norepinephrine reuptake inhibitors, approved for the treatment of depression and anxiety. Both are metabolized to inactive metabolites via cytochrome P450 enzymes. While previous studies have focused on quantifying VEN and ODV, bioanalytical methods for the simultaneous measurement of all metabolites are needed to fully characterize the pharmacology of VEN and ODV. METHODS: K2EDTA plasma was spiked with VEN, ODV, N-desmethylvenlafaxine (NDV), N,O-didesmethylvenlafaxine (NODDV), and N,N-didesmethylvenlafaxine (NNDDV). Drugs and metabolites were extracted via protein precipitation and quantified using liquid chromatography-tandem mass spectrometry (LC-MS/MS). The multiplexed assay was validated in accordance with regulatory recommendations, and evaluated in remnant plasma samples from persons prescribed venlafaxine. RESULTS: The analytical measuring range for venlafaxine and all four metabolites was 5-800 ng/mL. Standard curves were generated via weighted quadratic (NNDDV) or linear (VEN, ODV, NDV, NODDV) regression of calibrators. Inter-assay imprecision was between 1.9-9.3% for all levels of all analytes. Minor matrix effects were observed, and both recovery efficiency and process efficiency were >96% for all analytes. All other assay validation assessments met acceptance criteria. Drug concentrations measured from remnant plasma specimens obtained from patients with current venlafaxine prescriptions (37.5-450 mg/day) yielded NDDV, NDV, and NODDV metabolite concentrations in 6/21, 14/21, and 20/21 samples, respectively. The ratio of active to inactive analytes ranged from 0.74 to 14.5, with a median of 6.39. CONCLUSIONS: An efficient and accurate LC-MS/MS method was developed and validated for the quantification of VEN, ODV, and all three inactive metabolites in plasma. The assay met all acceptance criteria, and may be used in future studies of the pharmacokinetics of these drugs.

Sertraline versus venlafaxine combined with psychotherapy in trauma-affected refugees - a follow-up study on a pragmatic randomised trial.

BACKGROUND: Research on long-term pharmacotherapy for trauma-affected refugees is scarce. The purpose of this follow-up study of a randomised trial was to investigate the effects of sertraline compared to venlafaxine in combination with psychotherapy, 6 and 18 months after end of trial. METHOD: The primary outcome was PTSD symptoms, measured by the Harvard Trauma Questionnaire (HTQ). The secondary outcomes included: Hopkins Symptom Checklist-25 (HSCL-25), somatisation items of the Symptoms Checklist-90 (SCL), pain on a visual analogue scale, well-being on the WHO-5, Sheehan Disability Scale, Hamilton Depression and Anxiety scales and Global Assessment of Functioning. Moreover, the shorter version of the Recent Life Events (IRLE) was adopted to obtain information regarding the patients' treatment and life events between the follow-up periods. RESULTS: Out of 195 patients eligible for intention-to-treat analyses during trial, 116 participated in the 6-month follow-up and 97 participated in the 18-month follow-up. The results of our intention-to-treat analyses revealed no significant long-term differences between the groups on the primary outcome assessing PTSD symptoms (HTQ). For the secondary outcomes significant differences were found at the 18-month follow-up in favour of venlafaxine assessing symptoms of anxiety, depression and somatisation (HSCL-25 and SCL), although only in intention-to-treat and not per-protocol analyses. CONCLUSIONS: No conclusions could be drawn due to conflicting results between our intention-to-treat and per-protocol analyses.

Understanding the differential impacts of two antidepressants on locomotion of freshwater snails (Lymnaea stagnalis).

There is growing evidence of negative impacts of antidepressants on behavior of aquatic non-target organisms. Accurate environmental risk assessment requires an understanding of whether antidepressants with similar modes of action have consistent negative impacts. Here, we tested the effect of acute exposure to two antidepressants, fluoxetine and venlafaxine (0-50 µg/L), on the behavior of non-target organism, i.e., freshwater pond snail, Lymnaea stagnalis. As compounds interact with chemical cues in the aquatic ecosystems, we also tested whether the effects altered in the presence of bile extract containing 5α-cyprinol sulfate (5α-CPS), a characterized kairomone of a natural predator, common carp (Cyprinus carpio). Behavior was studied using automated tracking and analysis of various locomotion parameters of L. stagnalis. Our results suggest that there are differences in the effects on locomotion upon exposure to venlafaxine and fluoxetine. We found strong evidence for a non-monotonic dose response on venlafaxine exposure, whereas fluoxetine only showed weak evidence of altered locomotion for a specific concentration. Combined exposure to compounds and 5α-CPS reduced the intensity of effects observed in the absence of 5α-CPS, possibly due to reduced bioavailability of the compounds. The results highlight the need for acknowledging different mechanisms of action among antidepressants while investigating their environmental risks. In addition, our results underline the importance of reporting non-significant effects and acknowledging individual variation in behavior for environmental risk assessment.

The adsorption and its mechanism of venlafaxine by original and aged polypropylene microplastic and the changes of joint toxicity.

Conjugation with the increment of consumption of polypropylene (PP) masks and antidepressants during pandemic, PP microplastics (MPs) and Venlafaxine (VEN) widely co-existed in surface waters. However, their environmental fate and the combined toxicity were unclear. Hence, we investigated the adsorption behaviors, and associated mechanisms of PP MPs for VEN. The impact factors including pH, salinity, and MPs aging were estimated. The results indicated PP MPs could adsorb amount of VEN within 24 h. The pseudo second-order kinetic model (R2 = 0.97) and Dubinin-Radushkevich model (R2 = 0.89) fitted well with the adsorption capacity of PP MPs for VEN, implying that chemical adsorption accompanied by electrostatic interaction might be the predominant mode for the interactions between PP MPs and VEN. Meanwhile, the adsorption capacity of PP MPs declined from pH of 2.5-4.5 and then increased from 4.5 to 9.5. The increased salinity (5-35 ppt) significantly suppressed the adsorption capacity. Aging by sunlight and UV triggered the formation of new functional group (carbonyl) on MPs, and then enhanced the adsorption capacity for VEN. Gaussian Model analysis further evidenced the electrostatic adsorption occurring in PP MPs and VEN. The combined exposure to PP MPs and VEN showed significantly antagonistic toxicity on Daphnia magna. The adsorption of VEN by PP MPs mitigated the lethal effects and behavioral function impairment posed by VEN on animals, implying the potential protective effects on zooplankton by PP MPs. This study for the first time provides perspective for assessing the environmental fate of MPs and antidepressants in aquatic system.

Comparison of photoinduced and electrochemically induced degradation of venlafaxine.

The European Union requires environmental monitoring of the antidepressant drug venlafaxine. Advanced oxidation processes provide a remedy against the spread of micropollutants. In this study, the photoinduced and electrochemical decompositions of venlafaxine were investigated in terms of mechanism and efficacy using high-performance liquid chromatography coupled to high-resolution multifragmentation mass spectrometry. Kinetic analysis, structure elucidation, matrix variation, and radical scavenging indicated the dominance of a hydroxyl-mediated indirect mechanism during photodegradation and hydroxyl and direct electrochemical oxidation for electrochemical degradation. Oxidants, sulfate, and chloride ions acted as accelerants, which reduced venlafaxine half-lives from 62 to 25 min. Humic acid decelerated degradation during ultra-violet irradiation up to 50%, but accelerated during electrochemical oxidation up to 56%. In silico quantitative structure activity relationship analysis predicted decreased environmental hazard after advanced oxidation process treatment. In general, photoirradiation proved more efficient due to faster decomposition and slightly less toxic transformation products. Yet, matrix effects would have to be carefully evaluated when potential applications as a fourth purification stage were to be considered.

[Retrospective analysis of venlafaxine-induced hypoglycemia in patients with overdose]. / Análisis retrospectivo de las hipoglucemias inducidas por venlafaxina en pacientes con sobredosis.

INTRODUCTION: Recent publications relate the presence of hypoglycemia in venlafaxine (VLX) poisoning depending on the dose. Our aim was to analyze the clinical characteristics of patients who presented hypoglycemia induced by VLF overdose. PATIENTS AND METHODS: Retrospective study carried out in the Balearic Islands (2020-2023). INCLUSION CRITERIA: serum concentrations of VLX + O-desmethyl-venlafaxine (O-VLX)>800 ng/mL. The characteristics of patients with and without hypoglycemia were compared. RESULTS: Twenty-one patients were included, 8 (38.1%) with hypoglycemia. No differences were found in the doses referred to in both groups. Peak concentrations of VLX + O-VLX (ng/mL) were 9,783 [4,459-17,976] in patients with hypoglycemia and 1,413 [930-1,719] in patients without hypoglycemia (p<0.0001). The presence of hypoglycemia was associated with: lower age and level of consciousness; and higher frequency of suicide attempts, seizures, mydriasis, tachycardia and serotonin syndrome, invasive respiratory support, fluid therapy and ICU admission (p<0.05). CONCLUSIONS: The detection of hypoglycemia in a VLX overdose case is a readily available marker to suspect the severity of the patient. In any case, serum concentrations when available allow us to confirm intoxication.

Venlafaxine's therapeutic reference range in the treatment of depression revised: a systematic review and meta-analysis.

INTRODUCTION: The selective serotonin and norepinephrine reuptake inhibitor venlafaxine is among the most prescribed antidepressant drugs worldwide and, according to guidelines, its dose titration should be guided by drug-level monitoring of its active moiety (AM) which consists of venlafaxine (VEN) plus active metabolite O-desmethylvenlafaxine (ODV). This indication of therapeutic drug monitoring (TDM), however, assumes a clear concentration/effect relationship for a drug, which for VEN has not been systematically explored yet. OBJECTIVES: We performed a systematic review and meta-analysis to investigate the relationship between blood levels, efficacy, and adverse reactions in order to suggest an optimal target concentration range for VEN oral formulations for the treatment of depression. METHODS: Four databases (MEDLINE (PubMed), PsycINFO, Web of Science Core Collection, and Cochrane Library) were systematically searched in March 2022 for relevant articles according to a previously published protocol. Reviewers independently screened references and performed data extraction and critical appraisal. RESULTS: High-quality randomized controlled trials investigating concentration/efficacy relationships and studies using a placebo lead-in phase were not found. Sixty-eight articles, consisting mostly of naturalistic TDM studies or small noncontrolled studies, met the eligibility criteria. Of them, five cohort studies reported a positive correlation between blood levels and antidepressant effects after VEN treatment. Our meta-analyses showed (i) higher AM and (ii) higher ODV concentrations in patients responding to VEN treatment when compared to non-responders (n = 360, k = 5). AM concentration-dependent occurrence of tremor was reported in one study. We found a linear relationship between daily dose and AM concentration within guideline recommended doses (75-225 mg/day). The population-based concentration ranges (25-75% interquartile) among 11 studies (n = 3200) using flexible dosing were (i) 225-450 ng/ml for the AM and (ii) 144-302 ng/ml for ODV. One PET study reported an occupancy of 80% serotonin transporters for ODV serum levels above 85 ng/ml. Based on our findings, we propose a therapeutic reference range for AM of 140-600 ng/ml. CONCLUSION: VEN TDM within a range of 140 to 600 ng/ml (AM) will increase the probability of response in nonresponders. A titration within the proposed reference range is recommended in case of non-response at lower drug concentrations as a consequence of VEN's dual mechanism of action via combined serotonin and norepinephrine reuptake inhibition. Drug titration towards higher concentrations will, however, increase the risk for ADRs, in particular with supratherapeutic drug concentrations.

Biodetoxification Using Intravenous Lipid Emulsion, a Rescue Therapy in Life-Threatening Quetiapine and Venlafaxine Poisoning: A Case Report.

The administration of intravenous lipid emulsion (ILE) is a proven antidote used to reverse local anesthetic-related systemic toxicity. Although the capacity of ILE to generate blood tissue partitioning of lipophilic drugs has been previously demonstrated, a clear recommendation for its use as an antidote for other lipophilic drugs is still under debate. Venlafaxine (an antidepressant acting as a serotonin-norepinephrine reuptake inhibitor (SNRI)) and quetiapine (a second-generation atypical antipsychotic) are widely used in the treatment of psychotic disorders. Both are lipophilic drugs known to induce cardiotoxicity and central nervous depression. We report the case of a 33-year-old man with a medical history of schizoaffective disorder who was admitted to the emergency department (ED) after having been found unconscious due to a voluntary ingestion of 12 g of quetiapine and 4.5 g of venlafaxine. Initial assessment revealed a cardiorespiratory stable patient but unresponsive with a GCS of 4 (M2 E1 V1). In the ED, he was intubated, and gastric lavage was performed. Immediately after the admission to the intensive care unit (ICU), his condition quickly deteriorated, developing cardiovascular collapse refractory to crystalloids and vasopressor infusion. Junctional bradycardia occurred, followed by spontaneous conversion to sinus rhythm. Subsequently, frequent ventricular extrasystoles, as well as patterns of bigeminy, trigeminy, and even episodes of non-sustained ventricular tachycardia, occurred. Additionally, generalized tonic-clonic seizures were observed. Alongside supportive therapy, antiarrhythmic and anticonvulsant therapy, intravenous lipid emulsion bolus, and continuous infusion were administered. His condition progressively improved over the following hours, and 24 h later, he was tapered off the vasopressor. On day 2, the patient repeated the cardiovascular collapse and a second dose of ILE was administered. Over the next few days, the patient's clinical condition improved, and he was successfully weaned off ventilator and vasopressor support. ILE has the potential to become a form of rescue therapy in cases of severe lipophilic drug poisoning and should be considered a viable treatment for severe cardiovascular instability that is refractory to supportive therapy.

A reverse micelle-mediated dispersive liquid-liquid microextraction coupled to high-performance liquid chromatography for the simultaneous determination of agomelatine and venlafaxine in pharmaceuticals and human plasma.

An eco-friendly dispersive liquid-liquid microextraction mediated with a reverse micelle and coupled to an HPLC-DAD was developed for the simultaneous determination of venlafaxine and agomelatine in dosage forms and human plasma. All the parameters affecting the extraction efficiencies of both drugs were investigated and optimized. Under the optimal conditions, an effective analytes' preconcentration with enrichment factors (EFs) up to 72 was achieved. The linearity of the method was established over the concentration range of 0.50-70.0 and 3.0-100.0 ng/mL for venlafaxine and agomelatine, respectively with good correlation coefficients > 0.998. The method exhibited low detection limits in the range of 0.15-0.89 ng/mL and excellent precisions expressed in %RSD < 3% with average recoveries between 95.0 to 101.0%. The proposed method was employed to analyze the targeted analytes in dosage forms and human plasma samples with favorable characteristics like excellent enrichment, high sensitivity, great accuracy, and high precision. Finally, the greenness of the developed method was assessed using three distinct metric tools, confirming the greenness of the proposed method. The findings of this research could have more general implications for the extraction of other analytes from various matrices.

Adherencia al tratamiento, aceptabilidad y tolerabilidad de venlafaxina XR a dosis de 300 mg/día en pacientes con trastorno depresivo mayor / Adherence, acceptability and tolerability of venlafaxine extended release at dose of 300 mg/ day in patients with major depressive disorder

Introducción. La adherencia a los antidepresivos es fundamental para obtener buenos resultados en el tratamiento de la depresión. El objetivo del actual estudio fue evaluar la adherencia, aceptabilidad y tolerabilidad de venlafaxina XR a dosis de 300 mg/día, administrada en uno o dos comprimidos, tras un periodo de tratamiento de 6 ± 2 meses en pacientes con trastorno depresivo mayor (TDM). Metodología. Estudio observacional, transversal, de práctica clínica habitual en el que participaron 590 pacientes con TDM que asistían a consultas de centros públicos o privados de toda España, de los cuales 361 y 229 recibieron uno (300 mg) o dos comprimidos (150+150 mg o 225+75 mg) de venlafaxina XR, respectivamente. Los datos del estudio se obtuvieron de la entrevista con el paciente, de la historia clínica y de cuestionarios validados. Resultados. El método Haynes-Sackett y el cuestionario de Morisky-Green revelaron que la adherencia al tratamiento fue similar en ambos grupos. Los pacientes que recibieron la dosis de venlafaxina XR en un comprimido mostraron mayor satisfacción con el tratamiento según el cuestionario TSQM9. La escala MADRS reveló que en el 23% de los pacientes el TDM había remitido, y solo en el 9% se mantenía grave, en el 26% era moderado y en el 42% leve. Igual resultado se obtuvo con el cuestionario PHQ-9. En general, los pacientes mostraron buena tolerabilidad a la venlafaxina XR a dosis altas con las dos pautas de administración, y los efectos adversos más comunes fueron la disfunción sexual, sudoración y estreñimiento. Conclusiones. La adherencia al tratamiento con venlafaxina XR de 300 mg/día en uno o dos comprimidos fue similar. Los pacientes que recibieron un solo comprimido mostraron mayor satisfacción con el tratamiento. El perfil de seguridad de venlafaxina XR 300 mg fue favorable. No se produjeron abandonos, ni elevaciones clínicamente significativas de la presión arterial que condicionaran la pauta de uso. (AU)

Background. Adherence to antidepressants is essential for good outcomes when treating depressive disorders. The objective of the current study was to evaluate the adherence, acceptability and tolerability of venlafaxine XR at a dose of 300 mg/day, administered in one or two tablets, after a treatment period of 6 ± 2 months in patients with major depressive disorder (MDD). Subjects and methods. Observational, cross-sectional study of routine clinical practice in 590 outpatients with MDD who attended at public or private centers all over country, of whom 361 and 229 received one (300 mg) or two tablets (150+150 mg o 225+75 mg) of venlafaxine XR, respectively. The study data were obtained from the interview with the patient, the clinical history and validated questionnaires. Results. The Haynes-Sackett method and the MoriskyGreen questionnaire revealed that adherence to treatment was similar in both groups. The patients who received the dose of venlafaxine XR in one tablet showed greater satisfaction with the treatment according to the TSQM-9 questionnaire. The MADRS scale revealed that in 23% of the patients the MDD had remitted, and only in 9% it remained severe, in 26% it was moderate and in 42% mild. The same result was obtained with the PHQ-9 questionnaire. In general, the patients showed good tolerability to high doses of venlafaxine XR with both dosing regimens, and the most common adverse effects were sexual dysfunction, sweating and constipation. Conclusions. Adherence to treatment with venlafaxine XR 300 mg/day in one or two tablets was similar. Patients who received a single tablet showed greater satisfaction with the treatment. The safety profile of high dose venlafaxine was favorable and there was dropouts or clinically significant elevations that affected the dosing regimen. (AU)