Final answer:
Parenteral medications are absorbed, distributed, metabolized, and excreted differently than oral drugs, often achieving higher plasma levels through IV administration. The choice of administration route depends on drug absorption and patient needs, with parenteral routes requiring healthcare settings. Optimal dosage considers patient characteristics and drug pharmacokinetics.
Step-by-step explanation:
The pharmacokinetics of parenteral medications, such as intravenous (IV) and intramuscular (IM) injections, refer to how the drug is absorbed, distributed, metabolized, and excreted by the body. Compared to oral or IM administration, the plasma levels achieved by IV administration are substantially higher and occur more quickly, as indicated by the concentration-time curve in pharmacokinetic studies. This can be crucial for treating infections where timely and high levels of the drug in the bloodstream are necessary.
The routes of administration for drugs are chosen based on factors including the drug's absorption, the patient’s condition, and the convenience of administration. For systemic infections, oral administration is preferred for home use, as it is most convenient. However, if the drug is poorly absorbed in the gastrointestinal (GI) tract or the patient cannot ingest medications orally, parenteral routes are used. These typically require healthcare settings for administration.
When determining the optimal dosage and route of administration, several factors need to be considered, such as patient mass, potential side effects, history of liver or kidney dysfunction, and the drug's metabolic profile.