DRY POWDER INJECTIONS

 Environmental moisture is a great challenge for the drug manufacturers. As several drugs that are used for parenteral administration (i.e., non-oral administration) are unstable in an aqueous environment, they cannot be marketed as ready-to-use injectables. They are provided as dry powders which need to be reconstituted with a suitable vehicle just before administration. The vehicles are usually 5% dextrose solution, normal saline, bacteriostatic water, or sterile water for injection. Such drugs are called Dry Powder Injections, powder for constitution, powder for injection and powder for reconstitution. Typical molecules in this category include β-lactam antibiotics, cephalosporins and acyclovir.

Dry Powder Injections can be formulated by applying the following two strategies-

1.      Lyophilization - is a process that helps in the removal of water content from any substance so as to extend its shelf life. Lyophilization helps in the formulation of drugs that are heat sensitive or unstable under aqueous conditions. The core concept of lyophilization is freezing the material followed by the reduction of pressure and then adding heat to allow the frozen water in the material to sublimate.

The method of lyophilization involves following three steps;

a.       Freezing The principle behind this step is to cool the material below its triple point so as to ensures the sublimation of the material inspite of melting. This step preserves the physical form of the material. It is noteworthy that when the eutectic mixture (i.e., mixture of substances that melts at a single temperature lower than the melting point of any of its constituents) gets frozen, then only the solution is accepted as the frozen one.

b.      Primary Drying In this step, the pressure is decreased and heat is increased for the material leading to the sublimation. This helps in the manufacturing of a structurally intact product. Though this is the most time-consuming step, it is very important for getting the optimized product.

c.   Secondary Drying It is the adsorption step during which the Ionically-bound water molecules are removed. This is achieved by increasing the temperature higher than used in the primary drying or sublimation phase. The bonds are broken between the material and the water molecules. The continued drying is essential to reduce the remaining water content to an optimum level.

 2.       Crystallization – is the process through which the atoms or molecules are arranged into a well-defined, rigid crystal lattice or simply a crystal. The crystallization is maintained by directly filling the sterile dry-powder drug into presterilized vials.

The crystallization method is frequently used in pharmaceutical industries as it is cost effective and requires less infrastructure and efforts. Moreover, it requires less time to get a good amount of products.

Reconstitution of the Dry Powder Injections at the time of use can directly affect the health of a patient. Therefore, it is important to evaluate such formulations. Several inherent and external parameters can affect the time and reproducibility of reconstitution of Dry Powder Injections, hence, it is important to identify and control these parameters during product development.

Amster Labs is a highly dedicated Pharmaceutical Lab that is engaged in Manufacturing and Supplying high quality Dry Powder injections throughout India. Amster Labs take all the precautions while manufacturing its products.