Which of the following factors could affect the bioavailability of a drug?

The route of administration is a crucial factor that significantly influences the bioavailability of a drug. Bioavailability refers to the fraction of the administered dose of a drug that reaches systemic circulation and is available for therapeutic effect. Different routes of administration—such as oral, intravenous, intramuscular, or subcutaneous—can impact how quickly and effectively a drug is absorbed into the bloodstream.

For instance, a drug administered intravenously has 100% bioavailability since it directly enters the circulation, whereas an orally administered drug may undergo first-pass metabolism in the liver, leading to a lower percentage of the drug being available in systemic circulation. The characteristics of the drug formulation and the presence of food in the gastrointestinal tract can also affect absorption when taken orally, further illustrating the importance of the route chosen for administration.

Understanding the implications of various administration routes is essential for advanced practice nurse prescribers, as it allows for optimizing drug therapy based on the specific circumstances and needs of their patients.