Drug delivery systems administration routes

To date most drug delivery systems are designed to either overcome a barrier presented by or exploit an opportunity presented by a given route of administration. Often these two accomplishments are complementary. Each of the major routes present a unique set of barriers and exploitable characteristics. Consider the following major routes. 

Two basic questions arise from the biological system (excluding the route of administration discussed above) when the use of a polymeric drug delivery system is contemplated ... 

Before treating the various classes of sustained- and controlled-release drug-delivery systems in this chapter, it is appropriate to note that drug delivery may be incorporated in other chapters where the various classes of drug products and routes of administration are discussed. In addition, the reader is referred to Chapter 14 on target-oriented drug-delivery systems. 

Historically, the oral route of administration has been used the most for both conventional and novel drug-delivery systems. There are many obvious reasons for this, not the least of which would include acceptance by the patient and ease of administration. The types of sustained- and controlled-release systems employed for oral administration include virtually every currently known theoretical mechanism for such application. This is because there is more flexibility in dosage design, since constraints, such as sterility and potential damage at the site of administration, axe minimized. Because of this, it is convenient to discuss the different types of dosage forms by using those developed for oral administration as initial examples. 

Noninvasive drug delivery may require the administration of the drug delivery system (DDS) at an epithelium as a suitable site of absorption of the active compormd. Such regions are usually called mucosae. In the human body several mucosal sites can be identified, the one mostly used for administration and absorption of therapeutics being the gastrointestinal route. In order to increase the residence time at these absorption sites, a so-called mucoadhesive delivery system has to be used. Generally, these systems consist of one or more types of hydrogels. 

Mezei, M. and Gulasekharam, V, Liposomes a selective drug delivery system for the topical route of administration gel dosage form. J. Pharm. Pharmacol., 34,473-74, 1982. 

Mezei, M. and Gulasekharam, V., Liposomes — a selective drug delivery system for the topical route of administration lotion dosage form. Life ScL, 26, 1473-77, 1980. Fresta, M. and Pughsi, G., Survival rate improvement in a rat ischemia model by long circulating liposomes containing cytidine-51-diphosphate choline. Life ScL, 61, 1227-35, 1997. 

Duma RJ, Akers MJ, Turco SJ. Parenteral drug administration routes, precautions, problems, complications, and drug delivery systems. Chapter 2. In Avis KE, Lieberman HA, Lachman L, eds. Pharmaceutical Dosage Forms Parenteral Medications. 1. New York Marcel Dekker, Inc., 1992. 

DNLM 1. Drug Administration Routes. 2. Adjuvants, Pharmaceutic. 3. Drug Delivery Systems. WB 340 E58 2006]... 

The design of controlled release drug delivery systems should be done with a thorough knowledge of the anatomy and physiology of the route of administration. The different barriers and drug delivery considerations for each route are summarized below. 

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