Drug Therapy for Peptic Ulcer Disease and Hyperacidity: Medical Terminology and Clinical Concepts

Chapter 37: Drug Therapy for Peptic Ulcer Disease (PUD) and Hyperacidity

Definition and Etiology

• Peptic Ulcer Disease (PUD) is characterized by ulcer formation in the esophagus, stomach, or duodenum—areas of the gastrointestinal (GI) mucosa exposed to gastric acid and pepsin.

• Most cases are associated with infection by Helicobacter pylori or the use of nonsteroidal anti-inflammatory drugs (NSAIDs).

• Other contributing factors include physiological or psychological stress.

• Gastric ulcers are more common in older adults and tend to be chronic, while duodenal ulcers are strongly linked to H. pylori and NSAID use and can occur at any age.

Key Points

• Ulcers can occur in the esophagus, stomach, or duodenum.

• Gastric and duodenal ulcers are more prevalent than esophageal ulcers.

Example

• A patient with chronic NSAID use develops a duodenal ulcer confirmed by endoscopy.

Gastroesophageal Reflux Disease (GERD)

Definition and Pathophysiology

• GERD is the most common disorder of the esophagus, characterized by the regurgitation of gastric contents into the esophagus.

• Exposure of the esophageal mucosa to gastric acid and pepsin leads to symptoms and potential mucosal injury.

Clinical Features

• Acid reflux often occurs after evening meals and decreases during sleep.

• Pyrosis (heartburn) is the main symptom, worsened by recumbent position or bending over.

• Effortless regurgitation of acidic fluid, especially post-meal and at night, is indicative of GERD.

• Common in pregnancy and individuals over 40 years old.

Etiology

• Caused by an incompetent lower esophageal sphincter (LES).

• Contributing factors include certain foods, fluids, medications, gastric distention, cigarette smoking, and recumbent posture.

Medications for Upper GI Disorders

Therapeutic Goals

• Promote healing of lesions and prevent recurrence.

• Decrease cell-destructive factors and increase cell-protective mechanisms.

• Medications are used alone or in combination, depending on the clinical scenario.

Antacids

• Over-the-counter (OTC) drugs that neutralize gastric acid.

• Common formulations include mixtures of aluminum hydroxide and magnesium hydroxide, sometimes with calcium salts (e.g., Mylanta).

• Calcium compounds may cause hypercalcemia and acid rebound.

• Aluminum-containing antacids can cause constipation, hypophosphatemia, and osteomalacia with long-term use.

• Magnesium-containing antacids may cause diarrhea and hypermagnesemia.

• Older adults may experience neuromuscular effects.

Histamine2 Receptor Antagonists (H2RAs)

• Inhibit both basal and stimulated gastric acid secretion (stimulated by histamine, acetylcholine, and gastrin).

• Prototype: Cimetidine.

• Adverse effects (rare at standard doses): diarrhea, dizziness, drowsiness, headache, confusion, gynecomastia.

• Risks increase with high doses, prolonged use, older age, or impaired renal/hepatic function.

Proton Pump Inhibitors (PPIs)

• Strong inhibitors of gastric acid secretion; more potent and longer-acting than H2RAs.

• Prototype: Omeprazole.

• Provide faster symptom relief and healing in acid-related diseases.

• Adverse effects: nausea, diarrhea, headache; long-term/high-dose use may increase risk of bone fractures (due to hypocalcemia) and deficiencies in vitamin B12 and magnesium.

Comparison Table: H2RAs vs. PPIs

Feature	H2RAs (e.g., Cimetidine)	PPIs (e.g., Omeprazole)
Mechanism of Action	Block histamine2 receptors on parietal cells	Inhibit H+/K+ ATPase (proton pump) in parietal cells
Potency	Moderate	High
Duration	Shorter	Longer
Common Adverse Effects	Diarrhea, headache, dizziness	Nausea, diarrhea, headache, risk of fractures (long-term)

Adjuvant Medications

• Prostaglandin E analogs (e.g., Misoprostol): Inhibit gastric acid secretion, increase mucus and bicarbonate, and protect mucosa. Used with NSAIDs to prevent ulcers.

• Sucralfate: Binds to ulcerated mucosa, forming a protective barrier. Used for prevention and treatment of peptic ulcers; requires 4–8 weeks of therapy for healing.

• Combination therapy: For H. pylori infection, triple therapy (two antibiotics + acid reducer) or quadruple therapy (adds bismuth subsalicylate) is recommended.

• Bismuth subsalicylate: Coats ulcers, protects from acid, treats H. pylori, diarrhea, and nausea. May cause bleeding if used alone in ulcer patients.

Assessment and Risk Factors

Risk Factors for Peptic Ulcer Disease

• Cigarette smoking: Stimulates gastric acid secretion, decreases mucosal blood supply, slows healing, and increases recurrence.

• Stress: Both physiological (e.g., shock, sepsis, burns, surgery, trauma) and psychological stress can cause vasoconstriction and mucosal ischemia, leading to ulceration.

• Drug therapy: Use of aspirin, NSAIDs, corticosteroids, and antineoplastic agents increases risk.

Signs and Symptoms

• Symptoms depend on ulcer type and location.

• Chronic duodenal ulcer: Periodic epigastric pain (1–4 hours after eating or at night), described as "burning" or "gnawing."

• GI bleeding: Occurs when ulcers erode blood vessels; may be mild or severe.

• GERD: Presents with heartburn.

Nursing Interventions

Prevention and Management Strategies

• General health measures: Well-balanced diet, adequate rest, regular exercise.

• Avoid cigarette smoking and gastric irritants (alcohol, aspirin, NSAIDs, caffeine).

• Reduce psychological stress through environment changes or stress management techniques (e.g., relaxation, exercise).

• Long-term drug therapy: Small doses of H2RAs, antacids, or sucralfate may be used for maintenance.

• Diet therapy: Minor role; some physicians recommend avoiding highly spiced, gas-forming, or caffeine-containing foods.

GERD-Specific Interventions

• Avoid irritant, highly spiced, or fatty foods.

• Eat small meals; avoid lying down for 1–2 hours after eating.

• Elevate the head of the bed.

• Avoid obesity, constipation, or other conditions that increase intra-abdominal pressure.

Key Medical Terminology

• Peptic ulcer: A lesion in the lining of the stomach, duodenum, or esophagus due to acid and pepsin.

• Gastric acid: Hydrochloric acid secreted by parietal cells in the stomach.

• NSAIDs: Nonsteroidal anti-inflammatory drugs, which can damage GI mucosa.

• Proton pump: The H+/K+ ATPase enzyme responsible for acid secretion in the stomach.

• Histamine2 receptor: A receptor on parietal cells that stimulates acid secretion when activated.

• Pyrosis: Heartburn, a burning sensation in the chest due to acid reflux.

Relevant Equations and Scientific Concepts

• Gastric acid secretion involves the following reaction in parietal cells: $\mathrm{CO_2 + H_2O \xrightarrow{carbonic\ anhydrase} H_2CO_3 \rightarrow H^+ + HCO_3^-}$ $\mathrm{H^+}$ is secreted into the stomach lumen via the proton pump.

Additional info: The above notes expand on the pharmacological and pathophysiological concepts relevant to peptic ulcer disease and GERD, integrating medical terminology and clinical applications for comprehensive understanding.