Drugs that reduce the pH and/or volume of gastric acid are used for the treatment of hyperacidity conditions like gastritis, peptic ulcer disease and GERD (gastroesophageal reflux disease). The most commonly used drugs available for this are :
- Proton pump inhibitors (PPIs)
- H2-receptor blockers
Other drugs that may also be included in this regimen, including prostaglandin analogues and sucralfate. Medication to treat gastric hyperacidity may be combined with other drugs like antibiotics for the treatment of conditions like H.pylori gastritis.
Antacids are simply alkaline agents that reduce the pH of the stomach acid. This means that when an antacid chemically reacts with the gastric acid secretion, it makes the fluids less acidic. The action and side effects of this neutralizing base are discussed further under ANTACIDS.
Proton Pump Inhibitors and H2-Blockers
Both of these types of drugs reduce gastric acid secretion. Proton pump inhibitors are now the drug of choice although H2-blockers are still widely used. The actions and side effects of both drugs are discussed under PROTON PUMP INHIBITORS and H2-BLOCKERS.
A prostaglandin analogue like misoprostol can reduce gastic acid secretion and protects the stomach lining (gastric mucosa). These gastric mucosal protective properties are achieved by stimulating mucus production by the stomach lining and increasing bicarbonate secretion by the stomach cells. It has a short duration of action and must therefore be administered many times in a day.
Misoprostol causes diarrhea and abdominal pains and also triggers uterine contractions. It is therefore not suitable for pregnant women. Overall, it is not a popular drug due to the severity of the side effects as well as the need for multiple doses throughout the day.
Sucralfate is a sulfated salt of aluminum hydroxide-sucrose complex which dissociates in an acidic solution. It forms a thick paste that binds to the ulcers or erosions on the stomach lining and protects it from further damage by forming a physical barrier. Although it does not affect gastric acid secretion, sucralfates are effective in protecting the stomach lining against hydrochloric acid, pepsin and bile salts. It allows the stomach lining to heal while other drugs reduce the pH and/or volume of gastric secretions.
Sucralfate may bind to other drugs and interfere with its absorption. It should be considered carefully in patients using certain chronic medication. Sucralfates should not be used for prolonged periods in patients with renal insufficiency as a small amount of aluminum is absorbed to the bloodstream.