Loading Dose

A loading dose is one dose or a series of doses given at the onset of therapy with the aim of achieving the target concentration rapidly. The appropriate magnitude for the loading dose is:

A loading dose may be desirable if the time required to attain steady state (and efficacy) by the administration of drug at a constant rate (four half-lives) is long relative to the demands of the condition being treated as is the case with the treatment of arrhythmias or cardiac failure.

The use of a loading dose also has significant disadvantages. The patient may be exposed abruptly to a toxic concentration of a drug that may take a long time to fall (i.e., long ty2). Loading doses tend to be large, and they are often given parenterally and rapidly; this can be particularly dangerous if toxic effects occur as a result of actions of the drug at sites that are in rapid equilibrium with the high concentration in plasma. It is therefore usually advisable to divide the loading dose into a number of smaller fractional doses administered over time, or to administer the loading dose as a continuous intravenous infusion over a period of time using computerized infusion pumps.

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Blood Pressure Health

Blood Pressure Health

Your heart pumps blood throughout your body using a network of tubing called arteries and capillaries which return the blood back to your heart via your veins. Blood pressure is the force of the blood pushing against the walls of your arteries as your heart beats.Learn more...

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