Validation of Conversion Factors for Therapeutic Drug Monitoring of Lacosamide, Lamotrigine, and Levetiracetam in Dried Capillary Blood.

Background: Estimation of serum concentrations of antiseizure medications (ASMs) based on dried capillary blood is an alternative method for therapeutic drug monitoring of epilepsy. The aim of this study was to validate the conversion factors for lacosamide (LCM), lamotrigine (LTG), and levetiracetam (LEV), which were determined in an independent patient sample in a previous study, and identify the most accurate conversion method (simple ratio and regression).

Methods: Venous and capillary blood samples were collected from adult inpatients with epilepsy treated with LCM (n = 25), LTG (n = 27), and/or LEV (n = 29) before the morning dose (T1) and approximately 2 hours after (T2).

Therapeutic Drug Monitoring of Lamotrigine, Lacosamide, and Levetiracetam in Dried Capillary Blood-Determination of Conversion Factors for Serum-Based Reference Ranges.

Background: Drug concentrations of antiepileptic drugs (AEDs) are routinely determined from blood serum or plasma at trough levels (before intake of morning dose). In capillary blood collection, blood is taken from the fingertip with the aid of a disposable tool and dried on absorbent material. The volumetric absorptive microsampling technique offers several advantages over the use of filter paper cards.

Development and validation of an LC-MS/MS method for relevant drugs in epilepsy patients using dried blood spots.

Epilepsy is one of the most common diseases of the central nervous system globally. To ensure the correct dosage of antiepileptic treatment, it is helpful to check the blood levels of the administered substances regularly. The analysis of the capillary dried blood samples provides a promising and less-invasive alternative to venous blood collection.

Is urine an alternative to cosmetically treated hair for the detection of drugs and alcohol?

This study attempts to assess the utility of the urine matrix as an alternative to cosmetically treated hair for the detection of drugs and alcohol for driving licence re-granting in 1026 cosmetically treated hair samples and 33 262 urine routine samples. No significant difference was observed between the percentage positive samples in cosmetically treated hair to those in urine at both the 95% and 99% significance level for amphetamines, cocaine, opiates, benzodiazepines, and methadone. Significant difference was found between the positivity rates of cannabinoids in cosmetically treated hair and that in urine indicating urine to be a better alternative to the use of the hair matrix even when cosmetically treated.

Comparison of LUCIO®-direct ELISA with CEDIA immunoassay for 'zero tolerance' drug screening in urine as required by the German re-licensing guidelines.

The performance of the previously validated LUCIO(®)-Direct-enzyme linked immunosorbent assay (direct ELISA) screening tests according to forensic guidelines is compared to that of cloned enzyme donor immunoassays (CEDIA) test for drugs of abuse in urine as defined in the new re-licensing German medical and psychological assessment (MPA) guidelines. The MPA screening cut-offs correspond to 10 ng/ml 11-nor-delta-9-tetrahydrocannabinol-9-carboxylic acid (THC-COOH), 50 ng/ml amphetamine and designer amphetamines, 25 ng/ml morphine, codeine and dihydrocodeine, 30 ng/ml benzoylecgonine, 50 ng/ml methadone metabolite, 2-ethylidene-1,5-dimethyl-3,3-diphenylpyrrolidine (EDDP) and metabolites of diazepam, oxazepam, bromazepam, alprazolam, flunitrazepam and lorazepam at 50 ng/ml. Average relative sensitivities and relative specificities were 99.

Comparison of urine and hair testing for drugs of abuse in the control of abstinence in driver's license re-granting.

The purpose of the study was to compare the detection rate of illicit drugs in urine and hair specimens. The samples were taken from subjects trying to regain their revoked driver's license after a drug- or alcohol-related traffic offence. In 2010, we screened 14 000 urine and 3900 hair samples for amphetamines, methamphetamines, cannabinoids, cocaine, opiates, methadone, and benzodiazepines as well as for ethylglucuronide.

Significantly increased detection rate of drugs of abuse in urine following the introduction of new German driving licence re-granting guidelines.

In this paper we present the first assessment of the new German driving licence re-granting medical and psychological assessment (MPA) guidelines by comparing over 3500 urine samples tested under the old MPA cut-offs to over 5000 samples tested under the new MPA cut-offs. Since the enzyme multiplied immunoassay technique (EMIT) technology used previously was not sensitive enough to screen for drugs at such low concentrations, as suggested by the new MPA guidelines, enzyme-linked immunosorbent assay (ELISA) screening kits were used to screen for the drugs of abuse at the new MPA cut-offs. The above comparison revealed significantly increased detection rates of drug use or exposure during the rehabilitation period as follows: 1.

Ethyl glucuronide in hair - A highly effective test for the monitoring of alcohol consumption.

In Germany drink driving offenders lose their license and must prove abstinence for one year in order to regain it. In this paper we assess the newly introduced ethyl glucuronide (EtG) tests in urine and hair in this alcohol abstinence monitoring. 20% (80 out of 386) of the 3cm long hair samples were tested positive for EtG in hair, compared to only 2% (92 out of 4248 samples) in urine in the same time period.

Validation of a headspace solid-phase microextraction-GC-MS/MS for the determination of ethyl glucuronide in hair according to forensic guidelines.

The analysis of ethyl glucuronide (EtG) in hair is a powerful tool for chronic alcohol abuse control because of the typical wide detection window of the hair matrix and due to the possibility of segmentation, allowing evaluation of alcohol consumption in different periods. Additionally, EtG in hair is often the only diagnostic parameter of choice for alcohol abuse when other clinical parameters such as ALT, AST, gammaGT and CDT (asialotransferrin and disialotransferrin) are in the normal range and EtG in urine negative. In this paper, we describe the development, optimization and validation of a new method based on hair extraction with water, clean-up by solid phase extraction (SPE), derivatization with heptafluorobutyric anhydride and headspace solid-phase microextraction (HS-SPME) in combination with GC-MS/MS according to forensic guidelines.