Common Household Chemicals as Urinary Adulterants

People try to beat drug testing by adding adulterants into urine specimens. Several adulterants can cause false-negative results in drug testing by immunoassays. Common adulterants for masking drug testing are as follows and detection of these adulterants by specimen integrity tests is given in Table 2. 5. Golden Seal tea (produces dark urine). AlthoughFPIA is less subjected to interference from adulterants compared to the EMIT, some interference has also been reported with FPIA. Sodium...

Issues of Special Interest in Oral Fluid Testing

Although oral fluid can be collected under direct supervision and opportunity for sample adulteration is low, measurement of human IgG is recommended for sample validity. 2. To avoid adulteration, supervision of donor for 10-20 min is recommended prior to sampling. The donor should not put anything in his her mouth during this period. 3. To ensure that positive THC result, using point of care testing device, on an oral fluid specimen is from active exposure, SAMHSA proposes collection of a...

Drug Interactions with Piperine Major Constituent of Black Pepper

Piperine, a major constituent of black and long pepper, has been reported to act as bioavailability enhancer of several drugs by inhibiting drug metabolism and by increasing oral absorption. Bharadwaj et al. reported that piperine inhibits both the drug transported P-glycoprotein and the major drug metabolizing enzyme CYP3A4. Therefore, dietary piperine could affect plasma concentrations of drugs that are substrates of P-glycoprotein or CYP3A4 enzyme especially if administered orally 138 ....

Detection of Specific Drugs in Meconium

Although meconium is more easily collectable from a newborn as compared to urine, its analysis is considerably more difficult. Before analysis, it is important that the sample be homogenized, as meconium is a non-homogenous and is a gelatinous material. The methods of analysis include immunoassays for screening and GC-MS for confirmation. Although there is no FDA-approved immunoassay for drugs of abuse testing for meconium, the laboratories generally modify commercially available urine assays...

Pharmacokinetics and Metabolism of TCAs

Most of TCAs are well absorbed and reach peak plasma concentrations within 2-12 h. Owing to their lipophilic properties, they have a very large volume of distribution. Many of TCAs are tertiary amines and are metabolized by the cytochrome P450 isoenzyme system to secondary amines, which are also active. Some TCAs are metabolized to hydroxylated metabolites that may also be active and are further metabolized by glucuronidation. Some pharmacokinetics properties of TCAs are summarized in Table 1....