Rate-limiting steps in drug absorption

The rate process include                                                       

1.    disintegration of the drug product.                                 

2.    dissolution of the drug in an aqueous environment.       

3.    absorption across cell membranes into the systematic circulation.

In the later process of drug, the rate at which

drug reach the systemic circulation is determined by the slowest step in this series of rate processes is called the rate limiting step.