Related Experiment Video
Updated: Jul 14, 2026
08:18
Self-Nanoemulsification of Healthy Oils to Enhance the Solubility of Lipophilic Drugs
Published on: July 27, 2022
Estimating drug solubility in the gastrointestinal tract
J B Dressman1, M Vertzoni, K Goumas
1Department of Pharmaceutical Technology, Johann Wolfgang Goethe University, Frankfurt, Germany.
Advanced Drug Delivery Reviews
|June 30, 2007
Summary
Aqueous solubility poorly predicts oral drug absorption for lipophilic drugs. Biorelevant media better estimate gastrointestinal solubility and oral bioavailability than simple water solubility.
Area of Science:
- Pharmaceutical Sciences
- Drug Delivery
- Biopharmaceutics
Background:
- Aqueous solubility is often insufficient for predicting oral drug absorption, especially for lipophilic compounds.
- Using water solubility can lead to significant underestimations of oral bioavailability.
- Understanding luminal solubility is crucial for accurate drug absorption prediction.
Purpose of the Study:
- To discuss mechanisms enhancing drug solubility in the gastrointestinal tract.
- To present methods for estimating intra-luminal drug solubilities.
- To evaluate the predictive power of biorelevant media for oral drug absorption.
Main Methods:
- Discussing mechanisms of luminal solubility enhancement.
- Reviewing methods for estimating intra-luminal solubilities.
- Comparing solubility in human gastrointestinal fluids with biorelevant media.
Main Results:
- Biorelevant media simulate gastrointestinal fluids effectively.
- Biorelevant media provide better predictions of drug solubility in human aspirates.
- Case examples demonstrate biorelevant media's ability to predict plasma profiles.
Conclusions:
- Biorelevant media are superior to aqueous solubility for predicting oral drug absorption.
- Accurate prediction of oral bioavailability requires considering gastrointestinal tract conditions.
- Biorelevant media offer a valuable tool for drug development and formulation.
Related Concept Videos
01:21Factors Affecting Dissolution: Drug pKa, Lipophilicity and GI pH
Drug absorption within the gastrointestinal (GI) tract is a complex process influenced by several critical factors, including the site pH, the drug's dissociation constant (pKa), and the drug's lipophilicity. The GI tract exhibits a pH gradient, with an acidic environment in the stomach and a more alkaline environment in the small intestine. This pH variation directly affects the ionization state of drugs.
A drug's pKa and the pH of the gastrointestinal (GI) tract play crucial roles in drug...
A drug's pKa and the pH of the gastrointestinal (GI) tract play crucial roles in drug...
01:27Factors Influencing Drug Absorption: Drug Dissolution
The pharmacokinetic journey of drugs from solid oral dosage forms into systemic circulation is multifaceted. It begins with disintegration, a prerequisite ensuring a solid dosage form's subdivision into minute particles. Dissolution occurs next as these granulated entities solubilize in gastrointestinal fluids. This solubilization is crucial for the succeeding stage, permeation, which describes the traversal of the drug across the intestinal membrane and its subsequent entry into the blood...
01:20Factors 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...
01:22Factors Influencing Drug Absorption: Physicochemical Parameters
The physicochemical characteristics of drugs play a crucial role in formulating stable and bioavailable drug products. The solubility of a drug, governed by the varying pH along the GI tract and its dissociation constant (pKa), is pivotal in determining its ionization state and absorption rate. Notably, weak acids and bases remain unionized and are absorbed more rapidly.
Enhanced drug absorption can be achieved by reducing particle sizes and increasing surface areas, thereby facilitating...
Enhanced drug absorption can be achieved by reducing particle sizes and increasing surface areas, thereby facilitating...
01:16Bioavailability Enhancement: Drug Solubility Enhancement
Bioavailability is a critical factor in determining a drug's effectiveness. It refers to the proportion of a drug that enters the circulation when introduced into the body and is, as a result, able to have an active effect. Enhancing bioavailability is essential for drugs with poor solubility, as it can significantly impact their therapeutic efficacy. Various methods are employed to increase the solubility of drugs, thereby enhancing their bioavailability.Micronization and nanonization are...
01:19Drug Absorption: Factors Affecting GI Absorption
The process of oral drug absorption can be influenced by several factors. Weakly acidic drugs tend to be absorbed more readily from the stomach due to their nonionized state. However, absorption may be less efficient in the upper intestine, where drugs are often ionized. Interestingly, despite the stomach's apparent advantage for drug absorption, its mucous layer can hinder diffusion. Its surface area is also smaller than the intestine's, which can further slow down the absorption rate.
In...
In...