Gastritis and H. pylori: What Causes It, How It’s Treated, and What You Need to Know

Gastritis and H. pylori: What Causes It, How It’s Treated, and What You Need to Know

When your stomach feels like it’s burning from the inside, or you’re constantly nauseous after eating, it’s easy to blame stress or bad food. But if these symptoms stick around, it could be something more serious: gastritis. This isn’t just an upset stomach-it’s inflammation of the stomach lining, a protective barrier that normally shields your stomach from its own digestive acids. Left untreated, it can lead to ulcers, bleeding, and even raise your risk of stomach cancer.

Most cases of chronic gastritis are caused by a single culprit: Helicobacter pylori, or H. pylori. This bacteria lives in the stomach lining of nearly half the world’s population. In many people, it causes no problems. But in others, it triggers long-term inflammation that slowly damages the stomach over years. The good news? We know how to treat it-and we’ve gotten much better at it in the last five years.

What Gastritis Actually Looks Like

Gastritis isn’t one condition. It’s a spectrum. Some people have erosive gastritis, where the stomach lining breaks down visibly, sometimes leading to bleeding. Others have nonerosive gastritis, where the lining thins and changes at a cellular level, but no open sores form. The difference matters because symptoms and treatment vary.

Acute gastritis hits fast. You might wake up with sharp pain in your upper belly, nausea, and vomiting after taking NSAIDs like ibuprofen, drinking too much alcohol, or going through major stress. These cases often clear up in days with the right care.

Chronic gastritis is sneakier. You might feel off for months without knowing why. Up to half of people with H. pylori-related chronic gastritis have no symptoms at all. That’s why so many cases go undiagnosed until something worse happens-a bleeding ulcer, anemia from slow blood loss, or a cancer scare.

Warning signs you can’t ignore: black, tarry stools (a sign of digested blood), vomiting blood or material that looks like coffee grounds, or feeling dizzy and out of breath when you climb stairs. These aren’t normal. If you see them, see a doctor immediately.

H. pylori: The Silent Culprit Behind Most Gastritis

Before 1982, doctors thought stress and spicy food caused ulcers. Then two Australian scientists, Barry Marshall and Robin Warren, proved otherwise. They found H. pylori living in stomachs of people with ulcers and gastritis. Marshall even drank a culture of the bacteria to prove it caused illness-he got sick within days. They won the Nobel Prize in 2005 for changing medicine.

Today, H. pylori is responsible for 70-90% of stomach ulcers and the vast majority of chronic gastritis cases. It spreads through contaminated food, water, or close contact-like sharing utensils or kissing. In developing countries, over 70% of adults carry it. In the UK and US, it’s closer to 10-15%, but still affects millions.

The bacteria doesn’t just cause inflammation. It damages the cells that produce stomach acid and protective mucus. Over time, the stomach lining can thin out-a condition called atrophic gastritis. In some cases, the cells change type entirely, increasing cancer risk. That’s why treating H. pylori isn’t just about feeling better-it’s about preventing cancer.

How Doctors Diagnose It

There’s no single test for gastritis. Diagnosis starts with your symptoms and medical history. But to confirm H. pylori, doctors use one of three reliable methods:

  • Urea breath test: You drink a special solution, then breathe into a bag. If H. pylori is present, it breaks down the solution and releases carbon dioxide you exhale. This test is 95% accurate.
  • Stool antigen test: A stool sample is checked for H. pylori proteins. It’s cheap, non-invasive, and just as reliable as the breath test.
  • Endoscopy with biopsy: A thin tube with a camera goes down your throat. If your doctor sees inflamed tissue, they take tiny samples. This is the only way to confirm if the lining has thinned or changed cells, which matters for cancer risk.

Most people don’t need an endoscopy unless they’re over 50, have weight loss, vomiting, or bleeding. For younger people with typical symptoms, a breath or stool test is enough to start treatment.

A scientist drinking a glowing H. pylori culture, his body transforming into a flaming stomach in a surreal 1980s lab scene.

How H. pylori Is Treated: The New Standard

For decades, the go-to treatment was triple therapy: a proton pump inhibitor (PPI) like omeprazole, plus two antibiotics-usually amoxicillin and clarithromycin-for 10-14 days. It worked… sort of. Success rates dropped from 90% in the 1990s to 70-75% today because H. pylori has become resistant to clarithromycin.

In the UK and US, clarithromycin resistance is now over 35%. That means nearly 1 in 3 people treated with standard triple therapy still carry the bacteria afterward. That’s why guidelines changed.

Now, the preferred first-line treatment in high-resistance areas is bismuth quadruple therapy: a PPI, bismuth subsalicylate (like Pepto-Bismol), metronidazole, and tetracycline. It works in 85-92% of cases, even when clarithromycin fails.

Another option? Vonoprazan. Approved by the FDA in 2022, it’s a new type of acid blocker that works faster and stronger than PPIs. In clinical trials, vonoprazan-based therapy cleared H. pylori in over 90% of patients-even after two failed treatments. It’s not yet widely available in the UK, but it’s changing how doctors think about treatment.

Here’s what a typical 14-day regimen looks like now:

  1. Take a PPI (like omeprazole) or vonoprazan twice daily-30 minutes before breakfast and dinner.
  2. Take two antibiotics: metronidazole 500mg and tetracycline 500mg, four times a day.
  3. Take bismuth subsalicylate 525mg, four times a day.

Side effects? Common. Metallic taste, nausea, diarrhea, dark stools. But they’re temporary. The real risk is not taking the full course. Missing even one dose can let the bacteria survive and become stronger.

What Happens After Treatment

Finishing antibiotics doesn’t mean you’re cured. You need confirmation. That’s why doctors recommend a follow-up test-usually a urea breath test-4 weeks after treatment ends. Why wait? Antibiotics can give false-negative results if tested too soon.

If H. pylori is still there, you’ll get a second-line regimen. This might include different antibiotics like levofloxacin or rifabutin. Some patients need up to three tries to clear it. Don’t get discouraged. Persistence pays off.

Once it’s gone, your stomach lining can heal. Studies show that after successful eradication, the risk of stomach cancer drops by 50% over 10 years. That’s not a small win.

Other Causes of Gastritis (And How They’re Treated)

H. pylori isn’t the only cause. NSAIDs like ibuprofen, naproxen, or aspirin are the second biggest trigger. They block protective chemicals in the stomach lining. If you take them daily for arthritis or headaches, you’re at risk-even if you don’t feel symptoms.

Stopping the NSAID is the first step. If you can’t stop (like for heart protection), your doctor might switch you to a safer painkiller or add a PPI to protect your stomach.

Alcohol is another offender. More than 30g per day (about two pints of beer) doubles your risk. Cutting back or quitting can cut symptoms by 60% in just two weeks.

Then there’s autoimmune gastritis-rare, but serious. Your immune system attacks the stomach cells that make acid and intrinsic factor (needed for vitamin B12 absorption). This leads to B12 deficiency, anemia, and nerve damage. Treatment? Lifelong B12 injections or high-dose oral supplements. It’s not caused by H. pylori, so antibiotics won’t help.

A transparent human torso with a healing stomach as antibiotics rain down, H. pylori dissolving into smoke under a glowing checkmark.

What You Can Do at Home

Medication helps, but lifestyle changes make a real difference:

  • Stop smoking. Smoking slows healing and increases cancer risk. Quitting improves healing rates by 35%.
  • Avoid spicy, fatty, or acidic foods if they trigger symptoms. There’s no one-size-fits-all diet, but most people feel better cutting out coffee, citrus, tomatoes, and fried food.
  • Eat smaller meals. Large meals stretch the stomach and increase acid pressure.
  • Don’t lie down after eating. Wait at least 3 hours before going to bed.
  • Manage stress. While stress doesn’t cause H. pylori, it makes symptoms worse. Simple breathing exercises or walking daily can help.

Probiotics? Some studies suggest they reduce antibiotic side effects like diarrhea. Yogurt with live cultures or supplements with Lactobacillus and Bifidobacterium may help-but they won’t kill H. pylori on their own.

The Big Picture: Why This Matters

Gastritis isn’t just a nuisance. It’s a warning sign. In the UK, stomach cancer is the 15th most common cancer, and H. pylori is the top preventable cause. Treating it early saves lives.

But there’s a flip side: overtesting. Many people with mild, occasional indigestion get endoscopies they don’t need. Guidelines now say: if you’re under 50, have no red flags, and respond to acid blockers, you can be treated without endoscopy.

The goal isn’t to treat every single case of gastritis. It’s to treat the ones that matter-those caused by H. pylori, NSAIDs, or autoimmune issues. The rest? Monitor. Don’t overmedicalize.

And here’s the truth: if you’ve been told you have gastritis and you’re still feeling awful after treatment, ask your doctor: Did you confirm H. pylori was gone? If not, get a follow-up test. Too many people think they’re cured when they’re not.

What’s Next for Gastritis Treatment

Researchers are working on smarter ways to fight H. pylori. One trial is testing treatment based on the bacteria’s genetic profile-knowing which antibiotics it’s resistant to before you even start. Early results show 95% success rates.

Another focus: vaccines. No H. pylori vaccine exists yet, but trials are underway. If successful, it could prevent infection before it starts.

For now, the best tools we have are accurate testing, tailored antibiotics, and patient adherence. Don’t skip doses. Don’t stop early. And don’t ignore symptoms that come back.

Gastritis can be managed. H. pylori can be beaten. But it takes the right plan-and the right follow-through.

Can gastritis go away on its own?

Sometimes, yes-especially if it’s acute and caused by a one-time event like drinking too much alcohol or taking NSAIDs. Symptoms may improve in a few days if you stop the trigger. But if it’s caused by H. pylori, it won’t go away without treatment. Left untreated, chronic gastritis can lead to ulcers, bleeding, or even stomach cancer. Don’t assume it’s harmless just because it feels mild.

How long does H. pylori treatment take?

Standard treatment lasts 10 to 14 days. You’ll take a combination of medications twice or four times daily. Even if you feel better after a few days, you must finish the full course. Stopping early increases the chance the bacteria will survive and become resistant. After treatment, you’ll need a follow-up test-usually a breath or stool test-4 weeks later to confirm it’s gone.

Can I drink alcohol if I have gastritis?

No-not during treatment, and ideally not long-term. Alcohol irritates the stomach lining and makes inflammation worse. It also reduces the effectiveness of antibiotics and acid-reducing medications. Cutting out alcohol can reduce symptoms by up to 60% within two weeks. If you’re trying to heal, skip it completely.

Are PPIs safe for long-term use?

PPIs like omeprazole are safe for most people when used as directed. But long-term use (over a year) can lead to side effects like low magnesium, increased infection risk, or rebound acid reflux when you stop. If you’ve been on them for years, talk to your doctor about tapering off. Don’t quit cold turkey-symptoms can flare badly. Work with your doctor to find the lowest effective dose.

Does stress cause gastritis?

Stress doesn’t cause H. pylori or most forms of gastritis. But it can make symptoms worse by increasing acid production and reducing blood flow to the stomach lining. Severe physical stress-like from major surgery, burns, or trauma-can cause acute erosive gastritis. For everyday stress, managing it through sleep, exercise, or mindfulness can help you feel better, but it won’t cure the underlying cause.

Can H. pylori come back after treatment?

It’s rare, but possible. In the UK and US, reinfection rates are under 2% per year. Most relapses happen because the first treatment failed-not because you caught it again. That’s why follow-up testing is so important. If you live in a household where others have H. pylori, avoid sharing utensils or toothbrushes. Good hygiene helps prevent reinfection.

Is there a blood test for H. pylori?

Yes, but it’s not reliable for diagnosing active infection. Blood tests detect antibodies, which stay in your system for years-even after the bacteria is gone. So if you had H. pylori five years ago and were treated, your blood test will still show positive. That’s why breath and stool tests are preferred-they only detect current, active infection.

What foods should I avoid with gastritis?

There’s no universal list, but most people find relief by avoiding: coffee (even decaf), alcohol, spicy foods, fried or fatty meals, citrus fruits, tomatoes, chocolate, and carbonated drinks. These don’t cause gastritis, but they irritate the lining and worsen symptoms. Eat slowly, in smaller portions, and keep a food diary to find your personal triggers.

If you’ve been living with stomach discomfort for months, don’t wait for it to get worse. Get tested for H. pylori. If you’re diagnosed, follow through with treatment. This isn’t just about feeling better today-it’s about protecting your stomach for the next 20 years.