Enteric Coating tablet/stomach
If a tablet is described as having an 'enteric coating' (e/c) or 'gastro-resistant' it means that there is a coating which is designed to hold the tablet together when in the stomach. This is quite clever science which relies on the fact that the stomach is acid and the intestines, where food goes after the stomach, are not. The coating is designed to hold together in acid conditions and break down in non-acid conditions and therefore release the drug in the intestines. There are three reasons for putting such a coating on a tablet or capsule ingredient:
- To protect the stomach from the drug
- To protect the drug from the stomach
- To release the drug after the stomach e.g. in the intestines
Our digestive system contains very harsh conditions that enable it to break down food efficiently.
When we take a typical (uncoated) tablet or capsule:
- The capsule or tablet is swallowed and travels down the esophagus to the stomach.
- In the stomach the tablet or capsule is churned and gyrated in highly acidic digestive secretions with pH 1‐4, for 45minutes to 2hours.
What happens to uncoated tablets and capsules?
- Stomach acid breaks down tablets and capsules to prematurely release active ingredients.
- Protects capsule or tablet contents from acidic environments of stomach
- After passing through the stomach allows capsule or tablet to break down easily in pancreatic juices in the Duodenum* (pH 6‐8).
- Protects gastric mucosa against direct impact of the drug substance.
- Enables absorption of ingredients, at their highest activity levels, in the small intestine.
In recent years, acetylsalicylic acid (ASA)has been prescribed for a host of indications. In addition to its uses as an analgesic, anti-inflammatory, and antipyretic agent, ASA now is indicated for use in the prevention and treatment of heart disease and stroke. A low daily dose, 75-100 mg, commonly is used in preventive ASA therapy. ASA has been regarded as a potential gastric irritant , and studies have shown that the incidence of gastric intestinal side effects may increase with regular use. Enteric coating of the tablets, therefore, is desirable for preventing stomach upset or irritation in those taking daily ASA therapy.