Abstract:
BACKGROUND:Several reports of loss of efficacy or adverse effects have been described after generic substitution of antipsychotics. To date, studies comparing serum drug levels in patients switched to generic antipsychotics in a standard clinical setting are lacking. The aim of this study was to investigate if switching to generic olanzapine in patients affected by schizophrenia is associated with differences in its serum concentrations and therapeutic response. METHODS:Preswitching and postswitching serum olanzapine concentrations were compared in schizophrenic outpatients who were switched from a chronic treatment with branded olanzapine to the same dose of its generic alternative. The Positive and Negative Syndrome Scale was concurrently administered to assess modifications in schizophrenia symptom control. RESULTS:A total of 25 patients (13 women and 12 men, mean age 41.2 ± 12.8 years) concluded the study. Mean olanzapine dose was 12.2 ± 5.4 mg/d. The mean olanzapine serum concentrations decreased from 27.7 ± 14.4 ng/mL during treatment with the branded formulation to 22.6 ± 12.3 ng/mL after switching to the generic formulation (P < 0.01). The log-transformed ratio of generic/brand-name olanzapine serum concentration at steady state was 0.81 (90% confidence interval: 0.72-0.91). The total Positive and Negative Syndrome Scale scores did not significantly change after switching from branded to generic formulation (49.6 ± 8.3 versus 48.6 ± 9.5, P = 0.777). No patient exhibited disease relapse or required dose adjustment after switching. CONCLUSIONS:Significantly lower serum olanzapine concentrations were found after switching from branded to generic olanzapine. Although these modifications did not significantly impair schizophrenia symptoms control, it cannot be excluded that a longer exposure to lower olanzapine serum concentrations may result in relapse of schizophrenic symptoms. Generic substitution should be considered as an indication for therapeutic drug monitoring in psychiatry.
journal_name
Ther Drug Monitjournal_title
Therapeutic drug monitoringauthors
Italiano D,Bruno A,Santoro V,Lanza G,Muscatello MR,Zoccali R,Spina Edoi
10.1097/FTD.0000000000000211subject
Has Abstractpub_date
2015-12-01 00:00:00pages
827-30issue
6eissn
0163-4356issn
1536-3694journal_volume
37pub_type
杂志文章abstract::The concentration of haloperidol in hair was measured by radioimmunoassay after hairs were dissolved in 2.5 N NaOH solution and the drug was extracted. In patients to whom haloperidol had been administered at fixed daily doses for more than 1 month, and in whom therapy had been just discontinued (group A, n = 5) or th...
journal_title:Therapeutic drug monitoring
pub_type: 杂志文章
doi:10.1097/00007691-198911000-00013
更新日期:1989-11-01 00:00:00
abstract::The study assessed the removal of mycophenolic acid (MPA) and its major glucuronide metabolite (MPAG) during continuous venovenous hemofiltration (CVVHF) and continuous venovenous hemodiafiltration (CVVHDF) in 4 heart transplant recipients treated for at least 6 days with mycophenolate mofetil (MMF) in addition to cyc...
journal_title:Therapeutic drug monitoring
pub_type: 杂志文章
doi:10.1097/FTD.0b013e3181633667
更新日期:2008-02-01 00:00:00
abstract::The ring sulfoxidation of thioridazine (THD), a widely used neuroleptic agent, yields two diastereoisomeric pairs, fast- and slow-eluting (FE and SE) thioridazine 5-sulfoxide (THD 5-SO). Until now, studies in which concentrations of these metabolites were measured in THD-treated patients have revealed no significant d...
journal_title:Therapeutic drug monitoring
pub_type: 杂志文章
doi:
更新日期:1991-07-01 00:00:00
abstract:BACKGROUND:Human immunodeficiency virus (HIV)-infected individuals show large interindividual variation in response to antiretroviral therapy. Efavirenz (EFV) and nevirapine (NVP) are nonnucleoside reverse transcriptase inhibitors, which are prescribed in combination with other antiretroviral therapy in so-called highl...
journal_title:Therapeutic drug monitoring
pub_type: 杂志文章
doi:10.1097/FTD.0b013e31824868f3
更新日期:2012-04-01 00:00:00
abstract:BACKGROUND:Oral fluid (OF) is being developed as a specimen for the determination of drug intake as an alternative to serum and plasma. It is generally considered as an attractive specimen due to the noninvasive nature of the sampling procedure and the relation to the free fraction of drug in the blood. These features ...
journal_title:Therapeutic drug monitoring
pub_type: 杂志文章
doi:10.1097/FTD.0000000000000493
更新日期:2018-04-01 00:00:00
abstract::We describe the case of a pediatric patient on azathioprine therapy with previously undiagnosed homozygote thiopurine S-methyltransferase (TPMT) deficiency, resulting in myelotoxic thiopurine metabolite levels. The patient was successfully treated with a very low azathioprine dose of 50 mg once a week (4% of standard ...
journal_title:Therapeutic drug monitoring
pub_type: 杂志文章
doi:10.1097/FTD.0000000000000366
更新日期:2017-02-01 00:00:00
abstract::The authors report the use of high-performance liquid chromatography-electrospray-tandem mass spectrometry (HPLC-ESI-MS/MS) for the quantification of indomethacin (IND) in plasma with microscale sample preparation. Plasma samples (100 microL) and mefanamic acid (internal standard [IS]), buffered to pH 3.5, were prepar...
journal_title:Therapeutic drug monitoring
pub_type: 杂志文章
doi:10.1097/00007691-199812000-00020
更新日期:1998-12-01 00:00:00
abstract::Aminoglycosides have rightly remained a cost-effective anti-microbial strategy for the treatment of gram-positive infections for some 25 years. However, in recent years there has been a review of the traditional thrice-daily administration regimen in favor of an extended dosing interval strategy that takes into accoun...
journal_title:Therapeutic drug monitoring
pub_type: 杂志文章,评审
doi:10.1097/00007691-199908000-00001
更新日期:1999-08-01 00:00:00
abstract::Accessing patient's veins for drug level sampling is not always feasible. The use of capillary sampling techniques is often utilized when venous access is hampered. In the therapeutic monitoring of patients, unexpected drug level results often occur that can be caused by a number of different factors. The possibility ...
journal_title:Therapeutic drug monitoring
pub_type: 杂志文章
doi:10.1097/00007691-199005000-00009
更新日期:1990-05-01 00:00:00
abstract::The interaction between valproic acid (VPA) and phenytoin (DPH) was examined during therapeutic monitoring in an epileptic outpatient population. Gas-liquid chromatographic methods were used to measure DPH and VPA concentrations. (1) In 12 patients on stable DPH regimens, the mean DPH level declined from 19.7 to 15.3 ...
journal_title:Therapeutic drug monitoring
pub_type: 杂志文章
doi:10.1097/00007691-197901020-00005
更新日期:1979-01-01 00:00:00
abstract::A minority of athletes continues to use prohibited drugs in sports to enhance performance. Athletes discovered using these drugs can be subject to severe penalties, often resulting in media and public scrutiny, especially at major events such as the Olympic Games. The International Olympic Committee (IOC) has set out ...
journal_title:Therapeutic drug monitoring
pub_type: 杂志文章,评审
doi:10.1097/00007691-200002000-00022
更新日期:2000-02-01 00:00:00
abstract::A sensitive method for monitoring serum piroxicam (Feldene) is described. The assay requires 1.0 ml of specimen and involves chloroform extraction from an acidified mixture followed by concentration and injection into a liquid chromatograph. Column effluent is monitored at 330 nm. Retention times of piroxicam and the ...
journal_title:Therapeutic drug monitoring
pub_type: 杂志文章
doi:10.1097/00007691-198306000-00017
更新日期:1983-06-01 00:00:00
abstract::The effect of heparin sodium on the assay of gentamicin using the fluorescence polarization immunoassay system was investigated with varying heparin and gentamicin concentrations. Heparin had no significant effect on gentamicin concentrations as measured by this system. ...
journal_title:Therapeutic drug monitoring
pub_type: 杂志文章
doi:10.1097/00007691-198409000-00011
更新日期:1984-01-01 00:00:00
abstract:BACKGROUND:Body weight may affect pharmacokinetic parameters in various ways and may therefore have a significant impact on the serum concentration of a drug at a given dose. Although patients with major depressive disorder frequently show an elevated body mass index, studies investigating the relation between body wei...
journal_title:Therapeutic drug monitoring
pub_type: 杂志文章
doi:10.1097/FTD.0b013e318237b0fa
更新日期:2011-12-01 00:00:00
abstract::The emergence of point-of-care assays enabling bedside testing such as the VerifyNow P2Y12 system might prove useful in clinical settings. The aim of this study was to evaluate the ability of the VerifyNow P2Y12 assay to estimate the inhibition of platelet aggregation provided by clopidogrel in the absence of baseline...
journal_title:Therapeutic drug monitoring
pub_type: 杂志文章,随机对照试验
doi:10.1097/FTD.0b013e3181757c59
更新日期:2008-06-01 00:00:00
abstract::Calculated creatinine clearance (CrCL) estimates are frequently used as estimates of aminoglycoside clearance (AGCL), despite being inadequately studied. Thirty surgical intensive care unit (SICU) patients with stable serum creatinines (0.6-6.3 mg/dl) and steady-state aminoglycoside levels were studied. A one-compartm...
journal_title:Therapeutic drug monitoring
pub_type: 杂志文章
doi:10.1097/00007691-198903000-00006
更新日期:1989-01-01 00:00:00
abstract:BACKGROUND:Tacrolimus is a narrow therapeutic index medication, which requires therapeutic drug monitoring to optimize dosing based on systemic exposure. MITRA microsampling offers a convenient, minimally invasive approach for the collection of capillary blood samples from a fingerprick versus conventional venous blood...
journal_title:Therapeutic drug monitoring
pub_type: 杂志文章
doi:10.1097/FTD.0000000000000847
更新日期:2020-12-03 00:00:00
abstract:BACKGROUND:Cyclosporine A (CsA) is used as a posttransplantation immunosuppressant drug, and careful monitoring of CsA concentration in whole blood is essential. A new automated electrochemiluminescence immunoassay (ECLIA) for CsA measurement has been assessed in a multicenter evaluation. METHODS:Residual EDTA whole b...
journal_title:Therapeutic drug monitoring
pub_type: 杂志文章,多中心研究
doi:10.1097/FTD.0000000000000068
更新日期:2014-10-01 00:00:00
abstract::The aims of this study were to determine the relationship between saliva and plasma methadone concentrations and the influence of variability in saliva pH. Saliva and plasma samples were taken before the daily dose of methadone in 60 patients undergoing methadone maintenance treatment (MMT). Saliva pH was measured imm...
journal_title:Therapeutic drug monitoring
pub_type: 杂志文章
doi:10.1097/01.ftd.0000164392.01779.db
更新日期:2005-10-01 00:00:00
abstract::The greater and more consistent absorption of cyclosporine from the microemulsion formulation (Neoral; Novartis Pharmaceuticals Ltd., Frimley, UK) when compared with that from the original form (Sandimmune; Novartis Pharmaceuticals Ltd., Frimley, UK) results in greater systemic exposure. Lung transplant recipients cou...
journal_title:Therapeutic drug monitoring
pub_type: 临床试验,杂志文章,随机对照试验
doi:10.1097/00007691-199902000-00004
更新日期:1999-02-01 00:00:00
abstract::The CYP2D6*10(*10) allele that causes decreased CYP2D6 activity is present in Asians with a high frequency of approximately 50%. We studied the effects of the *10 allele on the steady-state plasma concentrations of aripiprazole and its active metabolite, dehydroaripiprazole. The subjects were 63 Japanese patients with...
journal_title:Therapeutic drug monitoring
pub_type: 杂志文章
doi:10.1097/FTD.0b013e3182031021
更新日期:2011-02-01 00:00:00
abstract::Metabolism of thiopurine drugs--azathioprine, 6-mercaptopurine, and 6-thioguanine--has provided a powerful pharmacogenetic model incorporating polymorphism of the enzyme thiopurine methyltransferase (TPMT) and the primary active metabolite, thioguanine nucleotide (TGN). However, a sense of uncertainty about the useful...
journal_title:Therapeutic drug monitoring
pub_type: 杂志文章,评审
doi:10.1097/01.ftd.0000169061.52715.3e
更新日期:2005-10-01 00:00:00
abstract::An isocratic high-performance liquid chromatography method with amperometric detection for the assay of plasma salbutamol is described. The plasma extract is injected into the chromatographic system via a loop column. This insures the purification of the injected extracts and allows a simple and rapid liquid-solid ext...
journal_title:Therapeutic drug monitoring
pub_type: 杂志文章
doi:10.1097/00007691-199206000-00011
更新日期:1992-06-01 00:00:00
abstract::Tyrosine kinase inhibitors are the standard of care for the treatment of chronic myeloid leukemia or Philadelphia chromosome-positive acute lymphoblastic leukemia. Dasatinib is a second-generation tyrosine kinase inhibitor that has been shown to be efficacious in treatment of patients with chronic myeloid leukemia or ...
journal_title:Therapeutic drug monitoring
pub_type: 杂志文章,评审
doi:10.1097/FTD.0b013e3181f4d9c5
更新日期:2010-12-01 00:00:00
abstract::The clinical usefulness of cyclosporine is hampered by dose-limiting toxicities to the kidney that are not predicted by drug levels in serum or whole blood. Because of its lipophilic nature, circulating plasma lipoproteins may play a role in drug disposition. This study characterized the pharmacokinetic parameters of ...
journal_title:Therapeutic drug monitoring
pub_type: 杂志文章
doi:10.1097/00007691-199003000-00004
更新日期:1990-03-01 00:00:00
abstract:BACKGROUND:The International Interlaboratory Quality Control PROGRAM for Therapeutic Drug Monitoring of Antiretroviral Drugs in Human Plasma/Serum was initiated in 1999. We have previously published our experience during the first 10 years of the PROGRAM. Since 2010, 3 newly developed antiretroviral agents have been ad...
journal_title:Therapeutic drug monitoring
pub_type: 杂志文章
doi:10.1097/FTD.0000000000000089
更新日期:2014-12-01 00:00:00
abstract::Twenty-five healthy volunteers were given 100 mg caffeine orally and several estimates of cytochrome P450 1A2 (CYP1A2) activity were evaluated. The validation was performed by correlation of different parameters in plasma, saliva, and urine to two measures of caffeine clearance, CL(oral) and CL(137X-->17X) that served...
journal_title:Therapeutic drug monitoring
pub_type: 杂志文章
doi:10.1097/00007691-200008000-00008
更新日期:2000-08-01 00:00:00
abstract:BACKGROUND:Colistin is increasingly used as the last therapeutic option for the treatment of multidrug-resistant, Gram-negative bacterial infections. To ensure safe and efficacious use of colistin, therapeutic drug monitoring (TDM) is needed due to its narrow therapeutic window. This study aimed to evaluate the pharmac...
journal_title:Therapeutic drug monitoring
pub_type: 临床试验,杂志文章
doi:10.1097/FTD.0000000000000572
更新日期:2019-02-01 00:00:00
abstract:PURPOSE:Substance use disorder often coexists with other psychiatric disorders, resulting in the simultaneous use of recreational and prescription drugs. The authors aimed to identify potential pharmacokinetic and pharmacodynamic interactions between new psychoactive substances of the cathinone class and specific presc...
journal_title:Therapeutic drug monitoring
pub_type: 杂志文章
doi:10.1097/FTD.0000000000000682
更新日期:2020-02-01 00:00:00
abstract::A reverse-phase high-performance liquid chromatographic (HPLC) method for the measurement of lamotrigine (LTG) simultaneously with phenobarbitone (PB), phenytoin (PHT), and carbamazepine (CBZ) is described using hexobarbital as the internal standard. The method uses the chromophore at 307 nm to detect LTG in the prese...
journal_title:Therapeutic drug monitoring
pub_type: 杂志文章
doi:10.1097/00007691-199402000-00013
更新日期:1994-02-01 00:00:00