Composition of drug

To what extent are the rodent models of nicotine physical dependence and nicotine withdrawal syndrome valid representations of physical dependence and withdrawal syndrome in hnman tobacco users Validity can only be partial at best because of species differences and differences in the means, dnration and composition of drug exposnre (nicotine alone versus tobacco smoke). The differences between the models and hnman tobacco use phenomena will always be as important as the analogies. 

Compositions of drug-excipient blends used for I and assay results after 3 weeks of storage at 50°C in closed vials with 20% added water weights of all ingredients are in milligrams. 

The enantiomeric purity or composition of drugs, synthetic intermediates, analogs, etc., in bulk samples can be determined via chiral derivatiza-tion in laboratory research, manufacturing processes, dosage forms, quality control, etc. In these applications, limitations on the amount of material available are usually nonexistent, allowing for convenient derivatization and ready detection. In such derivatizations, 0.1-1.0 mg is typically the amount of analyte derivatized. 

The compendia cited give the composition of drugs and the chemical identity of their ingredients. Especially useful for this purpose are The American Drug Index and The Merck Index, the latter being international in scope. 

Counting polymorphs and solvatomorphs, delavirdine mesylate has been found in 12 different crystal forms, therefore presenting considerable difficulty in the determination of phase composition.63 Only through the combination of factor analysis with the quantitative IR technique could one develop a method useable in the characterization of research and production lots. The composition of drug lots consisting of mixtures of forms was identified through qualitative factor analysis, and quantitated using principal component analysis. Calibration models were developed for the determination of Form-VIII or Form-XH in Form-XI, and a standard error of prediction of 2.0% of either form was reported, with detection limits of 3-5%. 

Ma J, Stafford RS, Cockbum IM, et al. 2003. A statistical analysis of the magnitude and composition of drug promotion in the United States in 1998. Clin. Ther. 25 1503-1517. 

Information on the composition of drug products with marketing authorization is available on the web sites of some national drug regulatory authorities. Examples of excipients known to have caused bioinequivalence that would not have been predicted by dissolution testing include surfactants, mannitol and sorbitol. 

Both methods presented are based on statistical analyses of a large set of several thousands of proven dmg molecules. Therefore, both methods are only able to identify probable drugs by identifying their similarity to drug molecules already in existence. Unfortunately, most of these were developed many years ago, which is why current trends in drug development are missed. Shifts in the composition of drugs, such as use of other structural patterns or functional groups, are not con-... 

Taken together with regard to the determination of the isomeric composition of drugs, NMR has several advantages over HPLC ... 

The unique composition of drugs [17-20] assures a presence in their composition of an iodine complex, whose structure is unique and differs from the structure of iodine complexes in other known dmgs. In the active site species the molecular iodine interacts with the bio-organic ligands (polypeptides) and lithium halogenide and exhibits acceptor properties with respect to polypeptides and donor properties in relation to lithium halide. The of existence such iodine complex is the probable cause of the low toxicity of the drugs. 

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