Enteric coating

Enteric coating

An enteric coating is a barrier applied to oral medication that controls the location in the digestive system where it is absorbed. "Enteric" refers to the small intestine, therefore enteric coatings prevent release of medication before it reaches the small intestine.

Most enteric coatings work by presenting a surface that is stable at the highly acidic pH found in the stomach, but breaks down rapidly at a less acidic (relatively more basic) pH. For example, they will not dissolve in the acidic juices of the stomach (pH ~3), but they will in the higher pH (above pH 5.5) environment present in the small intestine. Materials used for enteric coatings include fatty acids, waxes, and shellac as well as plastics.

Drugs such as aspirin, which have an irritant effect on the stomach, can be coated with a substance that will only dissolve in the small intestine. Similarly, certain groups of Azoles (Esomeprazole, omeprazole, pantoprazole and all grouped azoles) are acid-unstable. For such types of drugs, enteric coating added to the formulation tends to avoid the stomach's acidic exposure, delivering them instead to a basic pH environment (intestine's pH 5.5 and above) where they do not degrade, and give their desired action.

Recently, some companies have begun to utilize enteric coatings on fish oil (omega 3 fatty acids) supplements. The coating prevents the fish oil capsules from being digested in the stomach, which has been known to cause a fishy reflux.Sometimes the abbreviation "EC" is added beside the name of the drug to indicate that it is enteric coated.

Composition of coatings

* Cellulose acetate phthalate (CAP)
* methyl acrylate-methacrylic acid copolymers
* cellulose acetate succinate
* hydroxy propyl methyl cellulose phthalate
* polyvinyl acetate phthalate (PVAP)
* methyl methacrylate-methacrylic acid copolymers

ee also

* Phthalates

External links

[http://medical-dictionary.thefreedictionary.com/coating%2c+enteric Definition of "enteric coating" in the free dictionary website]

Although many approaches to enteric coatings have been used, one of the most successful commercial compounds was developed in the early 1930s by Milton Wruble, PhD. This took place while he was a graduate student at the University of Wisconsin. The patent was sold to the Upjohn Company in Kalamazoo, MI in exchange for a small amount of cash and a job as a research scientist. Dr. Wruble worked as a researcher for Upjohn until he retired in 1965. He died later that year in Washington, D.C.


Wikimedia Foundation. 2010.

Игры ⚽ Нужно решить контрольную?

Look at other dictionaries:

  • Enteric — can refer to: * A general term for the intestines ** Microorganisms that inhabit the intestines are commonly known as enteric bacteria * Enteric nervous system * Enteric coating that is often applied to pills and supplements * Enteric fever is a… …   Wikipedia

  • Enteric — Of or relating to the small intestine. * * * Relating to the intestine. [G. enterikos, from entera, bowels] * * * en·ter·ic en ter ik, in adj 1) of, relating to, or affecting the intestines <enteric diseases> broadly ALIMENTARY 2) being or… …   Medical dictionary

  • Enteric-coated — Coated with a material that permits transit through the stomach to the small intestine before the medication is released. The term enteric means of or relating to the small intestine. * * * en·ter·ic coat·ed (en terґik kōtґəd) a term… …   Medical dictionary

  • enteric — adjective Date: 1833 1. of, relating to, or affecting the intestines; broadly alimentary 2. being a coating (as of an aspirin tablet) designed to pass through the stomach unaltered and disintegrate in the intestines …   New Collegiate Dictionary

  • Micro-encapsulation — is a process in which tiny particles or droplets are surrounded by a coating to give small capsules many useful properties. In a relatively simplistic form, a microcapsule is a small sphere with a uniform wall around it. The material inside the… …   Wikipedia

  • Tablet — For other uses, see Tablet (disambiguation). Common disk shaped tablets A tablet is a pharmaceutical dosage form. It comprises a mixture of active substances and excipients, usually in powder form, pressed or compacted from a powder into a solid… …   Wikipedia

  • Omeprazole — Systematic (IUPAC) name (RS) 6 methoxy 2 ((4 metho …   Wikipedia

  • pharmaceutical industry — Producers of pharmaceuticals, substances used in the diagnosis, treatment, and prevention of disease and the modification of organic functions. The earliest records of medicinal plants and minerals are those of the ancient Chinese, Hindu, and… …   Universalium

  • Aspirin — Asprin redirects here. For the author, see Robert Asprin. Aspirin …   Wikipedia

  • Esomeprazole — Systematic (IUPAC) name (S) 5 methoxy 2 [(4 methoxy 3,5 dimethylpyridin 2 yl) methylsulfinyl] 3H benzoimidazole Clinical data …   Wikipedia

Share the article and excerpts

Direct link
Do a right-click on the link above
and select “Copy Link”