A nurse is preparing to administer diphenhydramine to a client who is to receive a blood transfusion. The nurse should explain that the purpose diphenhydramine is to prevent which of the following manifestations of a transfusion reaction?

A) H2-receptor blockers:
H2-receptor blockers, such as ranitidine and famotidine, are used to reduce the production of stomach acid. While they can provide symptomatic relief for ulcers by reducing acid secretion, they do not directly treat the underlying cause of the ulcer, which is the H. pylori infection.

B) Antacids:
Antacids are medications that neutralize stomach acid and can provide temporary relief from ulcer symptoms such as pain and discomfort. However, they do not eradicate the H. pylori bacteria or address the root cause of the ulcer. Antacids only provide symptomatic relief rather than treating the infection.

C) Proton-pump inhibitors:
Proton-pump inhibitors (PPIs), such as omeprazole and pantoprazole, are potent acid-suppressing medications that are commonly used to treat ulcers and gastroesophageal reflux disease (GERD). While they can help in ulcer healing by reducing acid secretion and providing symptomatic relief, they are not effective in eradicating H. pylori infection. PPIs are often used in combination with antibiotics for H. pylori eradication therapy, but they are not the primary treatment on their own.

D) Antibiotics.
H. pylori (Helicobacter pylori) is a bacteria that commonly infects the stomach lining and is a major cause of gastric and duodenal ulcers. Antibiotics are the primary treatment for H. pylori infection. The antibiotics kill the bacteria, allowing the ulcer to heal. Common antibiotics used to treat H. pylori include amoxicillin, clarithromycin, metronidazole, and tetracycline.

A) Chronic diarrhea:
Overuse of laxatives is more likely to lead to chronic constipation rather than chronic diarrhea. Laxatives are typically used to treat constipation by promoting bowel movements, but overuse can disrupt normal bowel function and result in long-term constipation.

B) Chronic constipation.
Overuse of laxatives can lead to dependence on laxatives for bowel movements and can cause the smooth muscle in the colon to become less responsive to normal stimuli, resulting in decreased muscle tone. This can eventually lead to chronic constipation, where the colon becomes less effective at moving stool through the digestive tract, resulting in infrequent or difficult bowel movements.

C) Frequent vomiting:
Overuse of laxatives does not typically lead to frequent vomiting. Vomiting is more commonly associated with conditions affecting the upper gastrointestinal tract, such as gastroenteritis, gastritis, or other gastrointestinal disorders.

D) Chronic nausea:
Overuse of laxatives may cause gastrointestinal discomfort or upset stomach, but it is not typically associated with chronic nausea. Chronic nausea may be caused by various factors such as gastrointestinal disorders, medications, or other underlying medical conditions unrelated to laxative use.