The enteric coating ensures that the tablet remains unaltered and stable in the stomach’s acidic pH (pH ~3) but breaks down and dissolves at higher pH (alkaline, pH 7–9) of the intestine. On the other hand, some drugs like aspirin and NSAIDs (Nonsteroidal anti-inflammatory drugs) can also cause side effects such as gastric irritation or nausea. The enteric coating protects the gastric mucosa from the drug itself. Another reason for enterically coated tablets is to provide a delayed release of the medication.

When preparing an enteric coating formulation, you need to pay attention to the mixing part. The mixture should be uniform and fine enough to pass through the coating system. The most common tablet coating equipment used for enteric coating is a pan coating system. This involves spraying the film-forming material onto the tablet surface as the tablets rotate in the pan.

Hot air is applied which helps the organic solvent evaporate and form the coat over the tablets. You need to repeat the process according to the desired thickness of the tablet’s film.

Enteric-coated tablets are pills that have a special coating designed to protect the active ingredients from stomach acid. While protecting, these tablets are still able to release the important API in the intestine. This feature is particularly important for drugs like naproxen and ibuprofen. Which have been known to cause irritation of the stomach lining. And thus, can cause ulcers. Enteric coated tablets are commonly used in the treatment of arthritis and inflammation and can be found at most local pharmacies.