Digestive system drugs

There are various kinds of digestive diseases with the medication being highly complex and diverse. For the treatment of reflux esophagitis and esophageal diseases, we should apply antacids drugs, especially cimetidine (Tagamet) and so on. H2 receptor blockers have efficacy of neutralizing gastric acid for suppression of gastric acid secretion and reducing the stimulation effect. In recent years, the discovery of metoclopramide (domperidone)’s effect on enhancing the lower esophageal sphincter (LES) tension and its selection application has led to the improved prognosis.

Peptic ulcer and chronic gastritis are common digestive system diseases with high incidence rate and many treatment drugs. However, to date, we are still lack of specific treatment. Antacids drugs for neutralizing gastric acid are still widely used. Conventionally applied sodium bicarbonate, calcium and magnesium have been gradually eliminated. At present time, the commonly used drug is aluminum hydroxide. This drug should be taken in 1 ~ 2h after a meal and can neutralize the stomach acid for up to 3h. Its combination with anticholinergic drugs can alleviate spasm pain as well as inhibit the gastric acid secretion in the evening, doing good to eliminate the peptic ulcer.

At the 1950th to 1960th of the 20th century, commonly used anticholinergic drug is probanthine (propantheline bromide). After the 1970s when the H2 blockers have emerged, the efficacy of treating peptic ulcer has been significantly improved. With the progress of the study, ranitidine, famotidine and other new generations of H2 receptor blocker with stronger antacid effect and reduced side have been applied to clinical practice, leading to excellent results with rapid eliminated symptoms and increased ulcer healing rate.
It is noteworthy that, proton pump inhibitors – omeprazole (Losec) can not only strongly suppress the acid effect, but also increase gastric mucosal blood flow, strengthen the gastric mucosal barrier, playing a more active and effective role in the treatment of this disease.

Currently, the treatment of chronic gastritis, though, is not satisfactory, but for the treatment of bile reflux gastritis, application of aluminum hydroxide and sucralfate to adsorb bile salts and protect gastric mucosal barrier in combination with domperidone can yield good results. In recent years, it has been found that almost all kinds of duodenal ulcers can lead to antral gastritis with Helicobacter pylori (HP) lead to inflammatory lesions in more than 80% cases. Therefore, simultaneously application of some appropriate antibiotic treatment can play a good role in promoting ulcer healing, reducing the relapse, eliminating the inflammation and increasing the efficacy of treatment of peptic ulcer and chronic gastritis. Colloidal bismuth subcitrate can both stimulate mucus secretion, playing a protective role of protecting the gastric mucosal barrier and have certain effect on killing the HP. If being appropriately selected depending on the disease, the rational application of the drugs mentioned above can play a more effective role in improving the efficacy in treating peptic ulcer and chronic gastritis as well as improving the prognosis.

Pepsin and other digestive drugs are now known to have only limited efficacy. For the treatment of chronic pancreatitis caused protein, starch and fat indigestion, pancreatin (pancreatin tablets, multi-enzyme tablets) is still in use, but requiring larger doses to be effective.

There are not many domestic pharmaceutical formulations for treating constipation with commonly used laxatives including milk of Magnesia, phenolphthalein and liquid paraffin. There is very limited domestic application of antidiarrheal opiates agents. Commonly used include aluminum hydroxide gel and diphenoxylate. It is worth noting that the latter one has a similar effect as pethidine and is often prone to be addicted and thus being not appropriate for long-term use. Lactulose is a special indigestible type of disaccharide, being able to be decomposed into lactose and acetate in large intestine, playing the osmotic laxative effect. Acidified manure can inhibit the intestinal bacteria from producing ammonia, and enable ammonia to diffuse into the lumen of the colon. Therefore, it has effect of lowering blood ammonia, having certain therapeutic effect on the treatment of hepatic coma.

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