A client needs to rapidly achieve a therapeutic plasma drug concentration of a medication. Rather than wait for steady state to be achieved, the physician might order:

To rapidly achieve a therapeutic plasma drug concentration, a loading or priming dose is ordered. This dose quickly establishes the desired drug level. It is calculated by multiplying the volume of distribution by the desired plasma drug concentration. A maintenance dose, like choice A, is used to maintain the therapeutic level after the loading dose. Waiting for steady state without a loading dose would take five drug half-lives. Choice C, a medication with no first-pass effect, does not directly address the need for rapid attainment of therapeutic levels. While intravenous administration (choice D) offers excellent bioavailability, a single dose by this route may not achieve the desired therapeutic plasma concentration as rapidly as a loading dose.