Fast metabolizer

Encainide is almost completely absorbed from the GI tract. Eood may delay absorption without altering its bioavailabiUty. The dmg is rapidly metabolized in 90% of the patients to two principal metaboUtes, 0-demethylencainide (ODE) and 3-methoxy-O-demethylencainide (MODE), while the other 10% metabolize encainide slowly with Htde or no ODE or MODE formed. Encainide, ODE, and MODE are extensively protein bound 75—80% for encainide and ODE and 92% for MODE. Peak plasma concentrations are achieved in 30—90 min. Therapeutic plasma concentrations are very low the concentrations of ODE and MODE are approximately five times those of encainide. The findings with the metaboUtes are significant because ODE is 2—10 times and MODE, 1—4 times more effective than encainide as antiarrhythmics. The half-Hves for encainide in fast and slow metabolizers is 1—2 h and 6—12 h, respectively. The elimination half-life for ODE is 3—4 h and for MODE 6—12 h in fast metabolizers. Excretion occurs through the Hver and kidneys (1,2). 

Some in silico procedures are able to report the most likely position(s) of biotransformations in a molecular skeleton, thus suggesting the path forward to prevention [1], By using this information, fast metabolism can be modulated and... 

Most compounds with such high BCF and Log Ko values are highly bioaccumulative. The cychc siloxanes, however, also have a high rate of clearance from the body through exhaled breath and a fast metabolism, so they might not be as bioaccumulative as the BCF and Log ATqw values indicate [285, 294, 295]. Kierkegaard et al. [284] compared the bioaccumulation potential of D4, D5, and D6 with the one of PCB 180, a compound known to be very bioaccumulative. D5 was found to be more bioaccumulative than PCB 180 and D4 even more so. D6, however, was found to have a lower bioaccumulation potential than PCB 180. 

This reversible HDAC inhibitor has potency in low nanomolar ranges. ° TSA induces cellular differentiation, apoptosis and growth factor unresponsiveness when administered under regimental dosing and not under single dose administration. However, TSA showed poor results in clinical trials, likely due to a combination of poor biodistribu-fion and fast metabolism. 

Fast/Slow acetylators The metabolism of SP to AcSP is mediated by polymorphic enzymes such that 2 distinct populations of slow and fast metabolizers exist. Approximately 60% of the white population can be classified as belonging to the slow acetylator phenotype. These subjects will display a prolonged plasma half-life for SP (14.8 vs 10.4 hours) and an accumulation of higher plasma levels of SP than fast acetylators. Subjects who were slow acetylators of SP showed a higher incidence of adverse reactions. 

The halflife of THC concentration ranges between 0.8 to 9.8 days. There is too much human variation to even approximate how long THC will be detected in the urine of an individual. Infrequent users with a fast metabolism will have the shortest detection time. Frequent users with a slow metabolism will have long detection times. The only way to estimate a detection time is to consider the lower and upper bounds (3-45 days), and decide based on the factors I ve mentioned. 

Poor response to an adequate dose, raising doubts about unusual pharmacokinetics, such as excessively slow or fast metabolism, leading to unusually low or high blood levels... 

For example, a test dose may identify a fast metabolizer, who may require a higher dose there is no evidence, however, that this approach could accelerate response, an issue that needs to be tested in controlled trials. Further, only limited evidence exists that high doses will shorten the lag period for any psychotropic agent (e.g., divalproex sodium loading dose strategy). 

Fast metabolic adjustments (on the time scale of seconds or less) at the intracellular level are generally allosteric. The effects of hormones and growth factors are generally slower (seconds to hours) and are commonly achieved by covalent modification or changes in enzyme synthesis. 

Data with a polymodal distribution If we give a series of patients a standard oral dose of the anti-tuberculosis drug isoniazid, obtain a blood sample from each individual 6 h later and determine the isoniazid concentrations of those samples, the results will probably look like Figure 3.1. The data are bimodal, because the metabolism of isoniazid is genetically controlled and we all fall into one of two groups - fast or slow metabolizers. The fast metabolizers form the cluster at the low end of the concentration scale and the slow metabolizers form a distinct group with higher levels. 

Low water solubility, less potency against dmg-resistant HIV strains, and fast metabolism are three main obstacles that limit the development of DCK analogs. Additional analog design is likely to use DCP as a new lead to increase the potency against drug-resistant viral strains and improve water solubility and pharmacological properties. 

It was noticed that slow metabolizers would respond better to treatment, that is, the drug was more effective in these patients. This was because the level of the drug in blood and tissues was higher than in the fast metabolizers, and so the bacteria were more effectively destroyed. Unfortunately there was a negative aspect to this when adverse effects began to be detected. 

Drug disposition and metabolism are of essential significance in pharmaceutical research because of the interdependence of pharmacokinetic and pharmacodynamic processes. Limited intestinal absorption, inadequate distribution, fast metabolism, and toxic metabolites are some of the causes of failure of drug candidates during development. To reduce the rate of attrition resulting from such pharmacokinetic defects, disposition and metabolic studies should be initiated as early as possible in the screening of lead candidates. 

The development of a dual root structure will create a fast metabolizing growth system for your plants that utilizes the essential processes and benefits of both soil and hydroponic gardening. The end result Faster and more plentiful plant growth than either standard soil or hydroponics by itself. 

Clinically, this has been shown to make a difference in a small study in males, involving 10 Chinese and 9 Caucasian subjects the Chinese metabolized propranolol more rapidly, clearance was 76% higher, with a lower area under the curve (AUC) and plasma levels lower than that in the Caucasians at all time points. In this study, when dosage was adjusted upwards to equilibrate to Caucasian therapeutic blood levels, a greater response was noted in the Chinese subjects (lower blood pressure and pulse rate) (Zhou et al., 1990). Conversely, the presence of very fast metabolizers in a population may also vary. 

Bio luminescent methods provide researchers with unique opportunities to track growth and movement of cells in real-time and to non-destructively monitor fast metabolic changes with high sensitivity and specificity directly in a live animal or cell.10 13 Despite these evident advantages, few results have been reported on the application of bioluminescent methods for monitoring the processes of bacterial infection."... 

To assure rapid results immediately after sample withdrawal some companies have realized undiluted whole-blood analysis eliminating any preanalytical procedure, which is important especially with respect to fast metabolic substances. 

The product from Birch reduction of estradiol 3-methyl ether, nandrolone, 1-5, comprises one of the simplest androgens in the gonane series. This compound suffers extremely fast metabolic inactivation by attack at C17 most androgens consequently incorporate an additional substituent at that position. 

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