Drug-induced gastropathy (Gastropathy of Drugs) refers to adverse gastric reactions caused by medications, accounting for approximately one-third of drug-related side effects. Many oral medications can cause gastric discomfort, but sometimes even non-oral administration may lead to stomach-related symptoms such as nausea, vomiting, and loss of appetite.

bubble_chart Pathogenesis

The pathogenesis of drug-induced gastropathy mainly includes:

1. Drugs interfere with the synthesis of mucin by gastric mucosal epithelial cells, affecting the quality and quantity of gastric mucus; inhibit the synthesis of mucosal prostaglandins, and suppress the normal proliferation, renewal, and granulation tissue formation of mucosal epithelial cells, leading to the destruction of the gastric mucosal barrier, impaired repair, and resulting in gastric mucosal erosion and ulcer formation.

2. Drugs affect the normal secretion of gastric mucosal glands and stimulate the secretion of gastric acid and pepsin. Some drugs reduce platelet count, inhibit platelet aggregation, and lower prothrombin levels, leading to upper gastrointestinal bleeding.

3. Some drugs have irritant or corrosive effects on the gastric mucosa, such as potassium chloride and iron salts. Others disrupt gastrointestinal motility and the blood and lymphatic circulation of the gastric mucosa, thereby injuring normal gastrointestinal function.

bubble_chart Clinical Manifestations

The clinical manifestations of drug-induced gastropathy vary depending on the type of medication, dose, and whether it is combined with gastric irritants. However, the primary symptoms are gastric irritation and varying degrees of damage to the gastric mucosal barrier, leading to gastric symptoms. In severe cases, gastric ulcers and bleeding may occur.

such as aspirin, indomethacin, piroxicam, phenylbutazone, and ibuprofen can easily cause upper abdominal pain and discomfort. In severe cases, upper gastrointestinal bleeding may occur. Gastroscopy often reveals gastric mucosal inflammation, erosion, ulcers, and bleeding. Upper gastrointestinal bleeding is more common in adults and occasionally seen in infants and young children.

2. Antibiotics

Many oral antibiotics, such as tetracyclines, erythromycin, metronidazole, and nitrofurans, can easily cause nausea, vomiting, abdominal pain, and decreased appetite when taken orally. They may also exacerbate peptic ulcers or even lead to bleeding. Bralow et al. reported that oral penicillin, in addition to causing general gastrointestinal symptoms, can also induce acute abdominal pain and gastrointestinal bleeding. Intravenous injections of erythromycin, amphotericin, and mitomycin can also cause gastrointestinal symptoms, with occasional cases of digestive tract bleeding. Polymyxin has significant toxicity to gastric mucosal epithelial cells, leading to local ischemia of the gastric mucosa and promoting histamine release, resulting in gastritis and gastric mucosal injury.

3. Antineoplastic drugs

such as methotrexate, 6-mercaptopurine, and 5-fluorouracil can irritate the gastrointestinal mucosa, causing diffuse inflammation, mucosal swelling, erosion, or ulcer formation. Symptoms include nausea, vomiting, and poor appetite, leading to gastritis or gastric ulcers.

4. Adrenocorticosteroids

including ACTH and various glucocorticoids, can induce gastrointestinal ulcers or cause ulcer recurrence and worsening. Boland reported that the incidence of peptic ulcers reached 37% in patients treated with prednisone for rheumatoid arthritis. Gastrointestinal ulcers caused by adrenocorticosteroids are also known as steroid ulcers (Steroid Ulcer). Their clinical symptoms differ slightly from those of typical peptic ulcers. Pain is less predictable and often occurs insidiously. The condition may only be discovered when it is already severe, with complications such as bleeding or perforation, due to corticosteroids raising the pain threshold and reducing inflammatory responses. Therefore, close monitoring of gastrointestinal reactions is necessary before and during medication, especially for patients with pre-existing ulcers. Corticosteroids should be avoided in combination with salicylates, analgesic and antipyretic drugs, or anticoagulants. Alcohol should be avoided during treatment, and a high-protein, high-vitamin, and ulcer-friendly diet should be provided. Antacids and anti-ulcer medications may be used if necessary.

Sympatholytic agents such as reserpine and guanethidine can promote gastric acid secretion and increase gastrointestinal motility, increasing the risk of gastric ulcers. Phentolamine and phenoxybenzamine, which have histamine-like effects, can exacerbate gastric ulcer symptoms. Histamine-like drugs stimulate gastric acid and pepsin secretion, and frequent use can lead to ulcers or worsen existing ones. Oral hypoglycemic agents like tolbutamide and insulin injections can increase gastric juice secretion and acidity, raising the risk of ulcers. Betahistine (anti-vertigo agent) is an H₁-receptor agonist that stimulates gastric acid secretion and aggravates gastric ulcers. Additionally, high doses of nicotinic acid and vitamin B₆ can promote histamine release. Caffeine, thyroid hormones, aminophylline, estrogen, and captopril can all cause gastric symptoms and increase the likelihood of ulcer formation and bleeding.

bubble_chart Diagnosis

The main diagnostic criteria are the presence of gastric symptoms during medication use, with other potential causes ruled out. Fiberoptic gastroscopy reveals widespread congestion of the gastric mucosa, multiple erosions, bleeding spots, and superficial ulcers, sometimes with active oozing of blood in the stomach. The lesions are mostly located in the gastric body, with a few cases involving the lower esophagus and duodenum. Biopsy of the affected areas often shows inflammatory cell infiltration, superficial necrosis of the mucosa, and hemorrhage.

bubble_chart Treatment Measures

1. Discontinue the medication as soon as possible, pay attention to dietary adjustments, and reduce irritating foods.

2. Symptomatic treatment to protect the gastric mucosa, such as oral administration of aluminum hydroxide gel, 10-15ml each time, 3-4 times daily, or taking sucralfate, H₂

bubble_chart Prevention

1. Before medication, understand whether the patient has a history of ulcer or other gastric diseases, as well as liver disease.

2. Medication should have clear indications, and drugs that irritate the stomach should be used with caution.

3. When using adrenal corticosteroids, antipyretic analgesics, or antibiotics, closely monitor gastric symptoms during the course of treatment.

4. Some drugs should be administered in safer dosage forms, such as liquid potassium supplements, or enteric-coated aspirin for long-term use.

5. Avoid taking multiple medications simultaneously, especially those that irritate the stomach.

bubble_chart Differentiation

The main differential diagnoses include non-drug-induced esophagitis, gastric and duodenal lesions, peptic ulcers, gastric cancer, gastric mucosal prolapse, and non-ulcer dyspepsia.