*3.3.7 Dissolution*

The dissolution rate is defined as the quantity of drug substances dissolve per unit of time with specific circumstances of temperature and solvent conditions for liquid or solid interface. The process is termed dissolution. The dissolution rate can be determined with the help of the Noyes-Whitney Equation. The dissolution rate is the rate-limiting step at the site of absorption for drugs in solution. At the preformulation stage, scientists understand, how excipients, surface area, and particle size affect the dissolution behaviour of drug substances and ascertain whether the rate-limiting behaviour is dissolution mediated. The drug dissolution is followed by reaching into the systemic circulation and is dependent on the type of dosage forms like solid oral (tablets, capsules, and suspensions) and intramuscular (pellets or suspensions); the rate-limiting factor governs which type of drug administration route is optimum for a selected dosage form [3, 14].
