Question

Case Study 4 Gastrointestinal Drugs A 48-year-old man presents for evaluation of heartburn. He reports a burning feeling in his chest after eating. It is worse when he eats spicy food or tomato sauce. He is sometimes awakened at night by these symptoms. He has tried over-the-counter antacids and H2 blockers with partial relief. He is on no medications regularly. His examination today is normal. An upper gastrointestinal (GI) x-ray series reveals gastroesophageal reflux. Along with appropriate diet and lifestyle modifications, the doctor prescribes omeprazole. ı. What is the mechanism of action of omeprazole? (25pts.) 2. What is the mechanism of action of aluminum and calcium based antacid medications? (25pts) 3. What is the mechanism of action of H2-receptor antagonists? (25pts) 4. What diet and life style changes would the nurse teach this patient? (25pts)

Answer 1

ANSWER

1) Mechanism of action of Omeprazole.

         * Omeprazole is a proton pump inhibitor used for decreasing

            HCL (gastric acid) production in the stomach.

         * Action of proton pump is essential for production of gastric acid.

         * It act by inhibiting the gastric proton pump or H+/K+ ATPase

            pump of the parietal cells of the stomach.

         * Action of proton pump inhibitor (omeprazole) is a irreversible

           process.

2) Mechanism of action of Aluminium and calcium based antacids.

               * Aluminium and calcium based antacids are useful to

                 reduce gastric acidity.

           * They act by increasing the pH level in the stomach and

                  neutralize gastric acid (HCL) present in the stomach.

3) Mechanism of action of H2 receptor antagonists.

              * Neuroendocrine cells present in gastric glands is responsible

                  for release of nitrogenous compound histamine.

              * Histamine bind to the H2 receptors of the stomach and stimulate

                 parietal cells of the stomach to produce HCL.

              * H2 receptor antagonists act by blocking the H2 receptors in the stomach

                 thereby inhibit the binding of histamine to H2 receptors.

              * Blocking of action of H2 receptors leads to decrease production of HCL.

4) Teaching for this patient about diet and lifestyle changes.

            * Instruct the patient avoid foods that aggravate symptoms of GERD

               like tomatoes,citrus fruits,carbonated drinks,high fat content foods

               chocolates etc.

            * Educate the patient to change dietary pattern to small and frequent

               meals instead of large and heavy meals.

            * Teach the patient avoid use of substances which will increase acidity

               of stomach like caffine containing products and alcohol.

            * Instruct the patient to avoid habit opf eating just before sleep which may

              leads to flow of food contents into the esophagus.

            * Educate the patient he can use green leafy vegetables and organic herbs

              instead of fast foods to avoid heart burn.