All Routes Lead to Enhancement - Pharmaceutical Technology

Latest Issue

Latest Issue
PharmTech Europe

All Routes Lead to Enhancement
A recent book collects information about advances in drug-delivery enhancement for the major routes of administration.

Pharmaceutical Technology

Gurvinder Singh
The paucity of new chemical entities and increasing regulatory demands for safety have made drug-delivery improvements essential to drug-product design. In the preface to Enhancement in Drug Delivery, the editors state that "extensive literature [is] available on drug-delivery development and enhancement, however, it is fragmented into specific routes of administration, making it difficult to gain an integrated knowledge in this field." This problem is exactly why this text is timely and immensely needed to overcome the disadvantages of traditional administration.

The book comprehensively reviews the basics of drug absorption and methods for delivery enhancement through various routes of administration. Its eight parts address oral, rectal, buccal, transdermal, nasal, vaginal, ocular, and central nervous system (CNS) drug delivery. Each part contains chapters that describe the anatomy and basic biopharmaceutics for each route and strategies to enhance drug delivery. The chapters are written by 60 eminent contributors from around the world. Besides discussing their achievements in their areas of expertise, the contributors describe the drawbacks of various enhancers, review current and future approaches to enhancement, and list applications that might inspire new ideas for choosing the ideal promoter for a new application.

Enhancement in Drug Delivery, Elka Touitou and Brian W. Barry, Eds., CRC Press, Taylor & Francis Group, Boca Raton, FL, 2007, 633 pp., ISBN 0-8493-3203-6
The opening chapters provide an in-depth review of gastrointestinal anatomy, physiology, and permeation pathways and discuss enhancers such as surfactants, chitosan, and its derivatives. The role of enzyme inhibitors and secretory-transporter mechanisms also are reviewed. These chapters include examples, toxicities, and formulative approaches to improving the oral-drug bioavailability of lipophilic drugs. Chapters two and three discuss rectal and buccal and sublingual absorption, respectively, and analyze the effect of dosage forms and formulation approaches for these routes of delivery.

Eight chapters are devoted to transdermal delivery, starting with an in-depth description of the stratum corneum. The widest range of enhancement methods being investigated are for transdermal administration. Individual chapters review chemical, iontophoresis, electroporation, ultrasound, and combined methods of enhancement. By way of illustration, the book's discussion of peptide delivery includes the physiological factors affecting nasal delivery, examples of formulations, and challenges for nasal delivery of peptide drugs.

Vaginal drug absorption with chemical enhancers and strategies for improving bioavailability are also presented. Options for expanding ophthalmic pharmaceuticals and developing optimal drug carriers or systems to arrive at the eye are discussed. Lastly, a constructive evaluation of the most significant developments in CNS drug delivery and various strategies to overcome the blood–brain barrier were reviewed.

The editors provide a basic review of the theory behind various administration routes. This review is necessary to appreciate the permeation pathways, enzymes, and secretory-transport mechanisms required for drug delivery. Each chapter has subsections that provide detail, illustrative tables and figures, and references from the scientific literature. A chapter about the combination of drugs in drug delivery, however, would have helped clarify the roles of some drugs as enhancers.

Overall, Enhancement in Drug Delivery is an indispensable resource for pharmaceutical scientists. Its breadth of coverage introduces the subject to those new to the field, and its depth can benefit experienced scientists. The text could form the basis for graduate and postgraduate work in pharmaceutics, medicine, and health-related disciplines. The book is strongly recommended to libraries at universities and pharmaceutical companies.

Gurvinder Singh Rekhi, PhD, is a director of research and development at Elan Drug Delivery, Inc., 1300 Gould Dr., Gainesville, GA 30504, tel. 770.538.6321,


blog comments powered by Disqus
LCGC E-mail Newsletters

Subscribe: Click to learn more about the newsletter
| Weekly
| Monthly
| Weekly

What role should the US government play in the current Ebola outbreak?
Finance development of drugs to treat/prevent disease.
Oversee medical treatment of patients in the US.
Provide treatment for patients globally.
All of the above.
No government involvement in patient treatment or drug development.
Finance development of drugs to treat/prevent disease.
Oversee medical treatment of patients in the US.
Provide treatment for patients globally.
All of the above.
No government involvement in patient treatment or drug development.
Jim Miller Outsourcing Outlook Jim MillerOutside Looking In
Cynthia Challener, PhD Ingredients Insider Cynthia ChallenerAdvances in Large-Scale Heterocyclic Synthesis
Jill Wechsler Regulatory Watch Jill Wechsler New Era for Generic Drugs
Sean Milmo European Regulatory WatchSean MilmoTackling Drug Shortages
New Congress to Tackle Health Reform, Biomedical Innovation, Tax Policy
Combination Products Challenge Biopharma Manufacturers
Seven Steps to Solving Tabletting and Tooling ProblemsStep 1: Clean
Legislators Urge Added Incentives for Ebola Drug Development
FDA Reorganization to Promote Drug Quality
Source: Pharmaceutical Technology,
Click here