The one-compartment open model is a simplified approach used in pharmacokinetics to understand the distribution and elimination of a drug administered through an intravenous bolus. This model assumes rapid drug dispersal throughout the body and elimination using a first-order process. Key pharmacokinetic parameters, such as the elimination rate constant (k), half-life (t_1/2), and the apparent volume of distribution (V_d), can be estimated from this model. The elimination rateis calculated from the slope of a semilogarithmic graph of drug concentration versus time. The apparent volume of distribution V_d is a parameter that connects the drug amount in the body to its plasma concentration. It is calculated by dividing the drug dose by the plasma concentration after IV bolus administration.

In essence, the one-compartment open model offers vital pharmacokinetic parameters that elucidate drug behavior in the body, assisting in optimizing therapeutic outcomes and guiding dosage regimens.