Related Experiment Video

Updated: Jul 12, 2026

Coherent anti-Stokes Raman Scattering (CARS) Microscopy Visualizes Pharmaceutical Tablets During Dissolution
09:59

Coherent anti-Stokes Raman Scattering (CARS) Microscopy Visualizes Pharmaceutical Tablets During Dissolution

Published on: July 4, 2014

Bioavailability of theophylline following a rectally administered concentrated aminophylline solution

W D Mason, R C Lanman, E N Amick

    The Journal of Allergy and Clinical Immunology
    |August 1, 1980
    PubMed

    More Related Videos

    A Novel Approach for the Administration of Medications and Fluids in Emergency Scenarios and Settings06:59

    A Novel Approach for the Administration of Medications and Fluids in Emergency Scenarios and Settings

    Published on: November 9, 2016

    An Intestine/Liver Microphysiological System for Drug Pharmacokinetic and Toxicological Assessment08:59

    An Intestine/Liver Microphysiological System for Drug Pharmacokinetic and Toxicological Assessment

    Published on: December 3, 2020

    Related Concept Videos

    Bioavailability: Overview01:13

    Bioavailability: Overview

    Bioavailability refers to the proportion of an unaltered drug that, after administration, enters the systemic circulation and can be distributed to the desired action site. Factors such as gastrointestinal (GI) absorption and liver biotransformation influence the bioavailability of a drug when it is administered orally. When a drug is administered intravenously, it enters the systemic circulation directly; by definition, its bioavailability is assumed to be 100%. The bioavailability of an...
    Antiasthma Drugs: Methylxanthines01:24

    Antiasthma Drugs: Methylxanthines

    Theophylline, a member of the methylxanthine class of bronchodilators, has long been used in asthma management. While its exact mechanism of action is not fully understood, it is believed to have multiple effects on various cellular processes.
    Theophylline is thought to inhibit phosphodiesterase enzymes, increasing intracellular levels of cyclic adenosine monophosphate (cAMP) and cyclic guanosine monophosphate (cGMP). This rise in cAMP and cGMP concentrations stimulates cardiac function,...
    Factors Influencing Drug Absorption: Presystemic Elimination01:24

    Factors Influencing Drug Absorption: Presystemic Elimination

    The pharmacokinetic journey of oral drugs begins with a crucial first pass through the hepatic portal system, called the first-pass effect. This first pass significantly impacts bioavailability — the proportion of a drug that enters systemic circulation and is available for therapeutic action. The primary route sees the drug absorbed by intestinal membranes and then shunted to the liver via the hepatic portal vein. Here, pre-systemic elimination occurs as drugs face metabolism or biliary...
    Factors Affecting Dissolution: Drug Permeability, Stability and Stereochemistry01:20

    Factors Affecting Dissolution: Drug Permeability, Stability and Stereochemistry

    Orally administered drugs primarily enter the systemic circulation via passive diffusion through the intestinal membranes. The drug's absorption is influenced by drug stability in the gastrointestinal GI tract, membrane permeability, the surface area available for absorption, luminal drug concentration, and residence time in the lumen. Drug permeability can be enhanced by adjusting the lipophilicity, polarity, or molecular size of the drug, promoting its passive transport across intestinal...
    Bioavailability: Overview01:17

    Bioavailability: Overview

    Bioavailability refers to the proportion of an administered drug that reaches the systemic circulation in its active, unaltered form. It is a crucial pharmacokinetic parameter that determines the effectiveness of a drug in achieving its intended therapeutic outcomes. The route of administration significantly influences bioavailability, with intravenous administration achieving 100% bioavailability as the drug directly enters the bloodstream. In contrast, oral administration often results in...
    IV Infusion to Oral Dosing: Conversion Methods01:28

    IV Infusion to Oral Dosing: Conversion Methods

    The development of extended-release formulations has facilitated the transition from intravenous to oral medication, offering a more convenient and patient-friendly approach to drug administration. This transition, however, requires careful management to ensure that therapeutic drug levels are maintained, preserving efficacy and avoiding adverse effects. Understanding pharmacokinetic principles and dosage calculations is critical during this process.Pharmacokinetics of the...