Adsorption at solid surfaces is involved in nearly every aspect of pharmaceutical development, from formulation design, process development, and manufacturing to storage of finished dosage forms. Achieving content uniformity, especially for low-dose drugs, exhibits a challenge faced in the manufacturing of solid dosage formulations. One of the solutions is by adsorbing small drug particles onto the surface of large excipients. The adsorption of binder solution onto solid surfaces is the basis for granulation, which can improve excipient properties such as flowability, compactibility, and bulk density. In compaction, moisture adsorption generally facilitates particle deformation and increases the area of contact between particles during compression. However, when compressible and non-compressible excipients are mixed together, the adsorption of non-compressible excipients onto the surface of compressible excipients will reduce mixed powder compressibility. During storage, water molecules adsorbed on solid surface have significant impacts on pharmaceutical development such as compaction and tensile strength of tablets. Therefore hygroscopicity needs to be taken into consideration for selecting excipients in formulation design.

Solid dispersion is frequently used to improve the dissolution rate of poorly water-soluble compounds. By adsorbing drug molecules onto the surface of adsorbents with large surface areas, the total surface area of the drug is increased, and the drug may even be transformed from crystalline form to amorphous form. By adsorbing a surfactant onto the crystal surface of poorly water-soluble drugs, dissolution rate can also be enhanced, even though the mechanism is yet not fully understood. In many approaches used to increase dissolution rate, because drugs exist in higher-energy state than their crystal state, dissolved or amorphous drugs can be crystallized and may cause a decrease in dissolution rate. To maintain a high dissolution rate, polymers have been widely used to inhibit crystallization by adsorbing onto crystal surfaces.

Besides process development and dissolution rate enhancement, the phenomenon of adsorption at solid surfaces is also useful in many other aspects of pharmaceutics. By adsorbing moisture onto its large surface area, colloidal silica has been frequently used as a desiccant for stabilizing moisture-sensitive drugs such as aspirin. Some special formulation designs, such as dry powder inhalation (DPI) and sublingual nitroglycerin tablets, have been designed based on the adsorption of drugs onto a carrier surface. Additionally, the adsorption of liquid and gas on solid surfaces is utilized to measure the surface area of solid materials.