Gastritis

Causes

• Bacterial infection: The most common cause of chronic gastritis is infection with Helicobacter pylori (H. pylori). This bacterium can live in the stomach lining and cause inflammation and ulcers.
• Regular use of nonsteroidal anti-inflammatory drugs (NSAIDs): Medications like ibuprofen, naproxen, and aspirin can irritate the stomach lining and cause both acute and chronic gastritis.
• Excessive alcohol consumption: Alcohol can irritate and erode the stomach lining.
• Stress: Severe physical stress from major surgery, burns, or severe infections can cause acute gastritis.
• Autoimmune gastritis: The body's immune system mistakenly attacks cells in the stomach lining.
• Bile reflux: A backflow of bile from the small intestine into the stomach.
• Other infections: Viral, fungal, or parasitic infections, though less common.
• Cocaine use: Can damage the stomach lining.
• Radiation therapy: To the stomach area.
• Crohn's disease: An inflammatory bowel disease that can affect the stomach.
• Aging: The stomach lining tends to thin with age, making it more susceptible to damage.

Symptoms

• Gnawing or burning ache or pain (indigestion) in your upper abdomen: This pain may worsen or improve with eating.
• Nausea.
• Vomiting.
• Feeling of fullness in your upper abdomen after eating.
• Loss of appetite.
• Bloating.
• Black, tarry stools (melena) or vomiting blood: These are signs of bleeding in the stomach and require immediate medical attention.

Diagnosis

• Medical history and physical exam: Your doctor will ask about your symptoms, lifestyle, medication use, and any relevant medical conditions.
• Tests for H. pylori:
  • Breath test: You drink a clear liquid, and then breathe into a bag.
  • Stool test: Checks for H. pylori antigens in your stool.
  • Blood test: Checks for H. pylori antibodies (less common for active infection).
• Endoscopy with biopsy: A thin, flexible tube with a camera (endoscope) is inserted down your throat into your stomach to visualize the stomach lining. A small tissue sample (biopsy) may be taken for microscopic examination to check for inflammation, H. pylori, or other abnormalities.
• Upper gastrointestinal (GI) series (barium swallow): X-rays are taken after you swallow a barium solution, which coats the stomach lining, making it visible on X-rays. This is less common for gastritis diagnosis but can help identify ulcers or other structural issues.
• Stool test: To check for blood in the stool, which can indicate bleeding in the stomach.

Treatment

• Treating H. pylori infection:
  • A combination of antibiotics and a proton pump inhibitor (PPI) is typically prescribed for 10-14 days to eradicate the bacteria.
• Avoiding irritants:
  • Discontinue or reduce the use of NSAIDs.
  • Reduce or eliminate alcohol consumption.
  • Avoid spicy, acidic, or fatty foods that can aggravate symptoms.
• Medications to reduce stomach acid:
  • Antacids: Over-the-counter medications that neutralize stomach acid for quick relief.
  • H2 blockers: Reduce acid production (e.g., famotidine, cimetidine).
  • Proton pump inhibitors (PPIs): Block acid production more powerfully than H2 blockers (e.g., omeprazole, lansoprazole, esomeprazole).
• Lifestyle changes:
  • Eat smaller, more frequent meals.
  • Manage stress through relaxation techniques.
  • Avoid smoking.
  • Identify and avoid personal food triggers.
• Vitamin B12 supplements: For autoimmune gastritis, as it can impair B12 absorption.

Treating Gastritis So It Does Not Come Back

Gastritis is usually easy to settle and often returns, because the thing that caused it was never addressed. Whether that is an untreated infection, a daily anti-inflammatory, or an autoimmune process determines what happens next, and each has its own follow-up.

H. pylori: treat fully, then prove it is gone

Because resistance to clarithromycin is now common in the United States, bismuth-based quadruple therapy, meaning a proton pump inhibitor such as omeprazole with bismuth, metronidazole, and tetracycline for fourteen days, is the preferred first course, with clarithromycin-based regimens reserved for people whose local resistance is known to be low. It is a demanding schedule with a metallic taste and dark stools; finishing every dose is what prevents a resistant, harder-to-treat second round. A breath or stool test four weeks or more after the last antibiotic, with acid suppression stopped for two weeks beforehand, confirms eradication. Our H. pylori infection page and the H. pylori and peptic ulcers article cover the regimens and the retesting rules.

NSAID gastritis: the drug has to change

Acid suppression heals the lining while ibuprofen or naproxen continues, but the injury resumes when the acid medication stops. Acetaminophen replaces the NSAID for most pain; when an NSAID is unavoidable, the lowest dose with a daily PPI, or celecoxib, limits the damage. Low-dose aspirin for heart protection is not stopped without discussing it, since the bleeding risk is managed with a PPI rather than by giving up the aspirin.

How long to stay on acid suppression

Four to eight weeks of a PPI is enough for most episodes, after which the dose is stepped down rather than stopped abruptly to avoid rebound acid. Sucralfate coats the inflamed lining and is an option when PPIs are not wanted. Staying on a PPI for years without a reason carries its own costs, which our long-term PPI use article explains.

Autoimmune gastritis needs lifelong follow-up

Loss of the acid-producing cells impairs absorption of vitamin B12 and iron, so both are checked yearly and replaced, often by injection for B12. It also raises the risk of stomach cancer and carcinoid tumors enough that surveillance endoscopy every few years is recommended, and it travels with Hashimoto's thyroiditis and type 1 diabetes, which are screened for.

What it is confused with, and the alarm signs

Upper abdominal burning is also produced by GERD, peptic ulcer disease, gallstones, and functional dyspepsia, and pain that comes with exertion or sweating is treated as cardiac until proven otherwise. New symptoms after 60, unintended weight loss, trouble swallowing, persistent vomiting, or anemia are reasons for endoscopy rather than a trial of acid suppression. Black tarry stools or vomiting blood or material like coffee grounds is an emergency. Our gastrointestinal team arranges testing and endoscopy. NIDDK and the American College of Gastroenterology publish patient guidance on gastritis and H. pylori.

If your stomach pain returns every time the acid medication stops, schedule a visit; something is still driving it.