Factors influencing stability of drugs and

Factors Influencing Stability of Drugs and Drug Products... 

FACTORS INFLUENCING STABILITY OF DRUGS AND DRUG PRODUCTS... 

The impact of formulation on protein absorption and disposition is also an important factor in the development and use of biologic molecules. Stability of the protein drug in subcutaneous or muscle tissues and absorption rates directly influence the overall response. Various physical and chemical approaches are used to stabilize proteins and other macromolecules as a part of optimizing dosage formulations. 

As with drugs and purified biomarkers, thermal- and photostability of botanical products are the factors that must be considered. Commercial dried extract and capsules of SJW were evaluated under harmonized test conditions (25). Photostability testing showed all the constituents to be photosensitive in the tested conditions. However, different opacity agents and pigments influenced the stability of the constituents. Amber containers had little effect on the photostability of the investigated constituents. Long-term thermal stability testing showed a shelf life of less than four months for hyperforins and hypericins, even when ascorbic and citric acids were added to the formulation. 

Peroxidation and free-radical formation should be considered as important aspects of pharmaceutical stability and quality of parenteral nutriton and intravenous drugs. Peroxidation and free-radical formation depend on environmental factors, such as storage conditions and container material, but are also influenced by formulation components or additives such as tocopherols and metabisulfite. Since the generation of these harmful species occurs generally at the time of use, manufacturing quality controls fail in demonstrating their existence. 

Major factors that influence distribution are the solubility (see Section 3.3) and stability (see Biological half life, Section 8.4.1) of drugs in the biological environment of the blood. Sparingly water soluble compounds may be deposited in the blood vessels, leading to restriction in blood flow. Drug stability... 

Stability Data Trending. Stability testing provides information about the quality of a drug product under the influence of a variety of environmental factors such as temperature, humidity, and light varying with time... 

Thus, biopharmaceutics involves factors that influence the 1) protection and stability of the drug within... 

The stability of a drug in the gut is influenced by both chemical and enzymatic factors. Protection from chemical degradation may be accomplished via coating... 

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