Related Experiment Video

Updated: Oct 1, 2026

Use of Rabbit Eyes in Pharmacokinetic Studies of Intraocular Drugs
10:02

Use of Rabbit Eyes in Pharmacokinetic Studies of Intraocular Drugs

Published on: July 23, 2016

Intra-arterial pharmacokinetics and pulmonary first-pass of levamisole in rabbits

Pablo Pereda1, Juan J García, Matilde Sierra

  • 1Area de Farmacología, Departamento de Farmacología, Toxicología y Enfermería, Universidad de León, 24071, León, Spain.

Pharmacological Research
|May 29, 2002
PubMed

Related Concept Videos

First Pass Effect01:12

First Pass Effect

Presystemic elimination, or the first-pass effect, is the metabolism of drugs that reduces their effective concentration at the site of action. Apart from the first-pass effect, the systemic bioavailability of the drug is also reduced by other factors, including incomplete absorption or chemical degradation of drugs.
Depending on the route of administration, drugs can be metabolized in the liver, intestine, lungs, and vasculature. Orally administered drugs are first absorbed through the...
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...
Routes of Drug Administration: Parenteral01:25

Routes of Drug Administration: Parenteral

The administration of drugs via parenteral routes allows for direct drug introduction into the systemic circulation, resulting in high bioavailability because the medication bypasses the harsh conditions of the gastrointestinal tract and hepatic metabolism.
The intravenous route (IV) of drug administration can be further categorized into two types. The bolus injection administers the entire dose rapidly, while an intravenous infusion slowly delivers smaller doses steadily.
The IV route is often...
Non-Oral Extravascular Drug Absorption Routes01:15

Non-Oral Extravascular Drug Absorption Routes

Non-oral extravascular routes, which encompass sublingual, buccal, topical, intramuscular, and inhalation methods, primarily utilize passive diffusion to transport drugs into the systemic circulation. The absorption rates and effectiveness of these routes depend on the drug's physicochemical properties, as well as the patient's anatomical and pathophysiological state.
Lipophilic drugs that are stable at salivary pH (6) and exhibit minimal binding to the oral mucosa are absorbed more effectively...
Compartment Models: Two-Compartment Model01:20

Compartment Models: Two-Compartment Model

The two-compartment model divides the body into central and peripheral compartments to account for varying blood perfusion rates among organs and tissues, affecting drug distribution. The central compartment includes blood and highly perfused tissues with rapid drug distribution, while the peripheral compartment contains tissues with slower drug distribution. After a single IV bolus dose, the drug concentration is high in plasma and low in tissues. The drug distribution between compartments...
Methods for Studying Drug Absorption: In situ01:09

Methods for Studying Drug Absorption: In situ

In situ experiments, such as the Doluisio method and Single-Pass Perfusion technique, provide critical insights into drug uptake by simulating in vivo conditions for drug absorption.
The Doluisio method involves perfusing a prepared segment of a rat's small intestine with a solution of radiolabeled drug and a non-absorbable marker. This helps to differentiate between absorbed and non-absorbed drug concentrations. The intestinal segment is connected at both ends using tubing and syringes,...