Which process is described as dissolution?

• A. Process of combining small drug particles with liquid to form a solution
• B. Breakdown of oral drug into smaller particles
• C. Movement from GI tract into bloodstream
• D. Metabolism

Answer: (A)

Dissolution is the process by which a solid drug dissolves in a liquid to form a solution, making the drug molecules available for absorption. This is best described by combining small drug particles with liquid to form a solution, because it captures the transition of the solid into dissolved form that can then be absorbed. In practice, the solid first must interact with the solvent, wetted by the liquid, and then solubilized so it becomes part of the solution. Disintegration—the breakdown of a tablet into smaller pieces—precedes dissolution, but it is not dissolution itself. Absorption is the movement of those dissolved molecules from the gastrointestinal tract into the bloodstream, and metabolism refers to the body's chemical modification of the drug. The rate of dissolution can influence how quickly and how much drug becomes available for absorption, and it depends on factors like solubility, particle size, surface area, agitation, and pH.