Impurities are critical quality attributes of drug substances and drug products because they have the potential to affect safety and efficacy of the product.
As per ICH Impurity is any component of the drug substance that is not the chemical entity that is defined as the drug substance; for a drug product, any component of a drug product that is not the drug substance or an excipient in the drug product.
Impurities can be classified into process impurities, degradation products, excipient, and packing related impurities. Process impurities are produced during the manufacture of the drug substance and drug product, while degradants are formed by chemical degradation during storage of the drug substance or drug product. Understanding the degradation pathways in order to achieve First to know the degradation paths to attain the stability of both drug substance and drug products.
The physical state such as solubility, dissolution, and disintegration of a drug will decide its physical characteristics in the final drug product. All these parameters will directly affect bioavailability and ultimately its efficacy. Additionally, it will also raise the safety issues for that drug product. Drug substances may exist in different physical forms such as amorphous form or various crystalline, hydrated, and solvated forms of the drug.
The following are the different forms of physical degradation.
Drugs is having several chemical natures along with different functional groups. Therefore, it will undergo different forms of degradation. Following is the different pathways of chemical degradation:
Stability study is very useful during formulation development and selection of packaging material.
Biological degradation states microbiological degradation. Liquids, Solutions, Suspensions, Parenteral, and sterile formulations are more susceptible to microbial degradation.
The following are the reasons for microbial degradation.