Biodisponibilitii

Biodisponibilitii is a term used to describe the extent and rate at which a substance administered to a living organism becomes available at the site of biological activity. In practice, it corresponds to the concept of bioavailability, commonly used in pharmacology, nutrition, and toxicology. The value depends on the route of administration and the formulation, among other factors.

In humans, biodisponibilitii is quantified through pharmacokinetic measures such as the area under the concentration–time curve (AUC), peak concentration (Cmax), and time to peak (Tmax). Absolute bioavailability compares a non-intravenous form with an intravenous reference, while relative bioavailability compares two formulations or routes.

Factors influencing biodisponibilitii include physicochemical properties of the substance (solubility, permeability, stability), dosage form and excipients, interaction with food or other drugs, first-pass metabolism, and physiological variables such as gastric pH, intestinal transit, age, disease states, and genetic differences in metabolism and transporters.

Applications include guiding drug development, dose optimization, and regulatory assessment of generic products through bioequivalence studies. In nutrition, bioavailability informs the assessment of nutrient absorption and utilization, while in toxicology it helps evaluate exposure risk.

Note: The standard term in many languages is bioavailability (or biodisponibilidade in Portuguese); "biodisponibilitii" appears to be a nonstandard variant. The article uses the term to discuss the same underlying concept.