Active ingredient, properties

That information about the composition, active ingredients, properties and effects of a drug may not be incorrect, misleading or unverified. 

P. H. Howard, ed.. Handbook of Environmental Fate andExposure Datafor Organic Chemicals, Vol. Ill, Pesticides, Lewis PubHshers, Chelsea, Mich., 1991. Provides chemical and physical properties of 70 pesticide active ingredients reviews data on environmental fate and exposure potential, with general references. 

Many attempts have been made to reduce the ammoniacal and sulfurous odor of the standard thioglycolate formulations. As the cosmetics market is very sensitive to the presence of impurities, odor, and color, various treatments of purification have been claimed to improve the olfactory properties of thioglycolic acid and its salts, such as distillation (33), stabilization against the formation of H2S using active ingredients (34), extraction with solvents (35), active carbon (36), and chelate resin treatments (37). 

Sodium and potassium benzoate are employed in a wide range of preservative appHcations because they provide an effective combination of antimicrobial action, low cost, and safety. Although sodium and potassium benzoate are the preservatives offered in the marketplace, the actual active ingredient being sold is free (or undissociated) benzoic acid. The benzoate ion has essentially no antimicrobial properties. Since it is the undissociated (free) benzoic acid that provides the antimicrobial action, sodium benzoate and potassium benzoate are recommended for use in appHcation areas where the pH is at 4.5 or lower (Table 8). 

Usually they are employed as porous pellets in a packed bed. Some exceptions are platinum for the oxidation of ammonia, which is in the form of several layers of fine-mesh wire gauze, and catalysts deposited on membranes. Pore surfaces can be several hundred mVg and pore diameters of the order of 100 A. The entire structure may be or catalytic material (silica or alumina, for instance, sometimes exert catalytic properties) or an active ingredient may be deposited on a porous refractory carrier as a thin film. In such cases the mass of expensive catalytic material, such as Pt or Pd, may be only a fraction of 1 percent. 

Typical properties of detergent alkylate are shown in Table 10-2. Detergent manufacturers buy linear alkylbenzene, sulfonate it with SO3, and then neutralize it with NaOH to produce linear alkylbenzene sulfonate (LABS), the active ingredient in detergents ... 

In 1960, the sedative, muscle-relaxing and anticonvulsant properties of 7-chloro-tV-methyl-5-phenyl-3//-l, 4-benzodiazcpin-2-amine 4-oxide ( chlordiazepoxide ) led to its introduction into clinical use as the active ingredient of the tranquilizer Librium . 

The different salts, esters, ethers, isomers, mixtures of isomers, complexes or derivatives of an active substance shall be considered to be the same active substance, unless they differ significantly in properties with regard to safety and/or efficacy, in which case additional safety and efficacy data are required. The same qualitative and quantitative composition only applies to the active ingredients. Differences in excipients will be accepted unless there is concern that they may substantially alter the safety or efficacy. The same pharmaceutical form must take into account both the form in which it is presented and the form in which it is administered. Various immediate-release oral forms, which would include tablets, capsules, oral solutions and suspensions, shall be considered the same pharmaceutical form for this purpose. 

The active ingredients in a shampoo play three fundamental roles. Some allow water to wash away the substances that make hair dirty. Others adhere to hair to impart a desirable feel and texture. The rest are emulsifiers that keep the mixture from separating into its components. To accomplish these effects, ingredients combine two types of interactions a strong attraction to water (hydrophilic) and an aversion to water (hydrophobic). It may seem that these properties are incompatible, but shampoos contain molecules that are designed to be simultaneously hydrophilic and hydrophobic. One example is sodium lauryl sulfate, our inset molecule. The ionic head of the molecule is hydrophilic, so it interacts attractively with water. The hydrocarbon tail is hydrophobic, so it interacts attractively with grease and dirt. Molecules of the shampoo associate with hydrophobic dirt particles to form hydrophilic clumps that dissolve in water and wash away. 

The effects of concentration or dilution of the active ingredient on the activity of a disinfectant are of paramount importance. Failure to be aware of these changes in activity is responsible for many misleading claims concerning the properties of a disinfectant. 

It does have a number of draw backs. It has poor thermal stability (a property common to most formaldehyde release biocides) and, in some instances, may cause blackening of metalworking fluid concentrates if heated above 50°C for a period of time. Recently, this active ingredient was placed on Annex 1 of the Dangerous Substances Directive having been identified as a potential skin sensitiser. This means that formulations containing efficacious levels of this class of triazine in them would have to be labelled with R43 - may cause sensitisation by skin contact. This is unacceptable to many UK customers. As this material is only bactericidal, it needs to be co-formulated with a fungicide to provide complete protection for a product. 

Those aspects critical to the in vivo bioavailability of the product and routine control tests proposed to ensure that the product has consistent bioavailability from batch to batch. Where a product has low in vivo absorption, the evidence should be discussed and a conclusion reached as to whether this is due to intrinsic properties of the active ingredient(s) or whether it is related to the properties of the dosage form concerned. In the case of products intended to have a nonsystemic effect, the potential for systemic absorption may need to be considered. This may involve specific studies to determine the levels of the active ingredient(s) in the blood, plasma, urine, or feces and a discussion of the clinical significance of those results. 

Additional guidance on the development pharmaceutics aspects of this type of product is included in document CPMP/QWP/604/96, adopted July 1999. This emphasizes the need for information on the rationale for the design of the product—e.g., therapeutic benefit, pharmacokinetics, and physical properties of the active ingredient. 

Factors affecting the mix of active ingredients and excipients should be discussed. These should include particle size and shape, rugosity, charge, flow properties, and water content. Since the dose delivery for these products is dependent on air flow characteristics, an attempt should be made to establish an in vivo-in vitro correlation. 

The physicochemical characteristics of the active ingredient in relation to the dosage form and the suitability for its intended purpose was discussed in several EPARs, particularly relating to the solubility characteristics and absorption from the gut. The compression characteristics were also mentioned in some EPARs. The possible effects of different polymorphs or evidence that only a single polymorph is used are addressed as appropriate. Different amorphous or crystalline forms are also discussed. Where affecting the dosage form, selection properties such as unpleasant taste or smell are mentioned. 

Trigard 75 WP is a new insecticide with a unique mode of action and a unique triazine structure. It is a solid formulated as a wettable powder and is packaged in water-soluble bags. The active ingredient in Trigard has the common name cyromazine. Cyromazine is a triazine, but, unlike the well-known triazine herbicides, this compound has insecticidal properties and no herbicidal activity. Cyromazine has low mammalian toxicity and low vapor pressure. It is hydrophilic, so dermal penetration is expected to be... 

Water uptake causes a host of problems in drug products and the inactive and active ingredients contained in them. Moisture uptake has been shown to be an important factor in the decomposition of drug substances [1-8]. Moisture has also been shown to change surface properties of solids [9,10], alter flow characteristics of powders [11,12], and affect the compaction properties of solids [13]. This chapter discusses various mathematical models that can be used to describe moisture uptake by deliquescent materials. 

US patent 6,723,728, Polymorphic and other crystalline forms cis-FTC [106], The present invention relates to polymorphic and other crystalline forms of (—)-and ( )-cA-(4-amino-5-fluoro-l-(2-(hydroxymethyl)-l,3-oxathiolan-5-yl)-2(lH)-pyrimidinone, or FTC) [106]. Solid phases of (—)-cz>FTC that were designated as amorphous (—)-FTC, and Forms II and III were found to be distinguishable from Form I by X-ray powder diffraction, thermal analysis properties, and their methods of manufacture. A hydrated crystalline form of ( )-cA-FTC and a dehydrated form of the hydrate, were also disclosed, and can similarly be distinguished from other forms of FTC by X-ray powder diffraction, thermal properties, and their methods of manufacture. These FTC forms can be used in the manufacture of other forms of FTC, or as active ingredients in pharmaceutical compositions. Particularly preferred uses of these forms are in the treatment of HIV or hepatitis B. 

It is now clear that the fate of chemicals in the environment is controlled by a combination of three groups of factors. First are the prevailing environmental conditions such as temperatures, flows and accumulations of air, water and solid matter and the composition of these media. Second are the properties of the chemicals which influence partitioning and reaction tendencies, i.e., the extent to which the chemical evaporates or associates with sediments, and how fast the chemical is eventually destroyed by conversion to other chemical species. Third are the patterns of use, into which compartments the substance is introduced, whether introduction is episodic or continuous and in the case of pesticides how and with which additives the active ingredient is applied. 

Because of the requirements of regulations for certain chemicals such as pesticides, extensive data usually exist on partitioning properties and reactivity or half-lives of active ingredients. In some cases these data have been peer-reviewed and published in the scientific literature, but often they are not generally available. A reader with interest in a specific pesticide can often obtain additional data from manufacturers or from registration literature, including accounts of chemical fate under field application conditions. Frequently these data are used as input to pesticide fate models, and the results of these modeling exercises may be available or published in the scientific literature. 

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