Other antiulcer drugs
Research continues on the usefulness of other drugs in treating peptic ulcer disease. Two other drugs currently in use are:
· misoprostol (a synthetic form of prostaglandin E1)
Each drug has a slightly different pharmacokinetic property.
After an oral dose, misoprostol is absorbed extensively and rapid-ly. It’s metabolized to misoprostol acid, which is clinically active, meaning that it can produce a pharmacologic effect. Misoprostol acid is highly protein-bound and is excreted primarily in urine.
Sucralfate is minimally absorbed from the GI tract and is ex-creted in stool.
The actions of these drugs vary.
Misoprostol protects against peptic ulcers caused by NSAIDs by reducing the secretion of gastric acid and boosting the production of gastric mucus, a natural defense against peptic ulcers.
Sucralfate works locally in the stomach, rapidly reacting with hy-drochloric acid to form a thick, pastelike substance that adheres to the gastric mucosa and, especially, to ulcers. By binding to the ulcer site, sucralfate actually protects the ulcer from the damaging effects of acid and pepsin to promote healing. This binding usually lasts for 6 hours.
Each of these drugs has its own therapeutic use.
Misoprostol prevents gastric ulcers caused by NSAIDs in the pa-tient at high risk for complications resulting from gastric ulcers. (See Dangers of misoprostol use during pregnancy.)
Sucralfate is used for the short-term treatment (up to 8 weeks) of duodenal or gastric ulcers and for the prevention of recurrent ul-cers or stress ulcers.
Misoprostol and sucralfate may interact with other drugs.
§ Antacids may bind with misoprostol or decrease its absorption. However, this effect doesn’t appear to be clinically significant.
§ Antacids may reduce the binding of sucralfate to the gastric and duodenal mucosa, reducing its effectiveness.
§ Cimetidine, digoxin, norfloxacin, phenytoin, fluoroquinolones, ranitidine, tetracycline, and theophylline decrease the absorption of sucralfate. (See Adverse reactions to other peptic ulcer drugs.)