Pyloric stenosis: a narrowing on the scan, and a question about what is really causing the symptoms.

A narrowed outlet sounds like an obvious explanation for your stomach symptoms. Whether it actually is depends on two things that can be measured.

This page is about understanding the condition and the role the brain and nervous system can play in it. It is not a diagnosis. Your own clinicians know your case.

Getting the diagnosis right

Pyloric stenosis in adults means the pylorus, the muscular valve between the stomach and the duodenum, has narrowed. The usual cause is scar tissue from a peptic ulcer, past or present, which can be associated with Helicobacter pylori infection or anti-inflammatory painkillers. Less often, the cause is a growth, which is why the diagnosis must be made properly by endoscopy with biopsy rather than assumed.

A significant narrowing causes gastric outlet obstruction: the stomach cannot empty, so food sits, and people experience vomiting of undigested food hours after eating, early fullness, bloating, weight loss and, over time, dehydration and salt imbalances. That picture is serious and treatable, with acid suppression, H. pylori eradication, endoscopic balloon dilation or surgery.

But many narrowings are mild. The scar is there on the scope, the stomach empties adequately, and no ulcer is active. In that situation the finding may be incidental, and the symptoms that led to the test need another explanation.

The neuroplastic contribution

Neuroplastic symptoms are real physical symptoms produced by learned pathways in the brain and nervous system, a sensitized alarm system, rather than by ongoing damage or disease. They are not imaginary, and because the brain can change, they are reversible.

The ATNS Index of Neuroplastic Symptoms makes a precise statement about pyloric stenosis: it usually does not cause symptoms unless there is an active peptic ulcer, or the narrowing is delaying the emptying of the stomach. If neither is present, the person's symptoms might be due to neuroplastic symptoms, and that should be assessed.

This matters because upper-gut symptoms are among the most common neuroplastic symptoms there are. Nausea, early fullness, upper abdominal pain and bloating with normal or mildly abnormal tests make up functional dyspepsia, a disorder of gut-brain interaction in which:

• The stomach's nerves are over-responsive (visceral hypersensitivity), so normal stretching after a meal feels like pain or sickness. This is the gut version of central sensitization.
• The stomach's relaxation reflex is impaired, producing fullness after small amounts of food without any mechanical block.
• Stress, anxiety and fear of eating amplify both, and the memory of a past ulcer or the word 'stenosis' can keep the alarm engaged long after the tissue has healed.

A scarred pylorus and a sensitized stomach can coexist. The question the index asks is which one is actually producing your symptoms.

What the research shows

The research on adult pyloric stenosis is about the structural condition, and it is sparse. A 2025 case report and review of adult hypertrophic pyloric stenosis secondary to chronic peptic ulcer disease describes it as rare and probably under-reported, lists recurrent peptic ulcer disease, malignancy and adhesions among its causes, and notes that history, examination and plain imaging often fail to settle the diagnosis, so endoscopy with biopsy is the reliable route.

A small prospective series of six consecutive adults with peptic pyloric stenosis found that proton pump inhibitor treatment was a feasible first-line alternative to surgery or balloon dilation, with the narrowing improving as the ulcer disease healed. That supports the index's point: when the ulcer is the driver, treating it resolves the problem.

For the symptom side, the closest evidence comes from functional dyspepsia, the name for upper-gut fullness, nausea and discomfort without a structural cause. A study of 94 people with functional dyspepsia in Japan measured how the stomach moved and emptied and found no association between motility abnormalities and the symptoms people reported. In other words, how full or sick someone feels does not reliably track how well the stomach is emptying, which is consistent with the nervous system setting the volume of these sensations.

No study has directly compared neuroplastic assessment with structural treatment in people with mild pyloric narrowing, so the ATNS position rests on the general evidence about functional upper-gut symptoms rather than condition-specific trials.

Signs the brain may be part of the picture

• Endoscopy shows a healed ulcer and a pylorus the scope passes through; gastric emptying is normal or near normal.
• No weight loss, no vomiting of old food, no salt imbalances.
• Symptoms fluctuate day to day, worsen with stress, and ease when you are relaxed or distracted.
• Fullness or nausea begins within minutes of starting a meal, or before eating, which is faster than any mechanical block.
• Acid suppression healed the ulcer but the symptoms stayed.
• Other sensitized-system conditions alongside: IBS, bloating, migraine, anxiety.

A solution that addresses it

Once an active ulcer and true obstruction are excluded, there is an approach that addresses the brain's contribution. Pain and symptom reprocessing includes education about neuroplastic symptoms, somatic tracking of fullness and nausea with curiosity instead of alarm, reducing fear of eating, a graded return to normal meals, emotional awareness and expression, and acceptance and commitment skills. Trained clinicians deliver it, and digital programs increasingly make it available every day.

Cindra is a daily AI companion built around these approaches, with daily check-ins, short practices and plain-language lessons for people whose symptoms have a neuroplastic component. If your stomach symptoms have outlasted your ulcer, join the waitlist. Our articles on functional dyspepsia and abdominal bloating cover the overlapping symptoms.

What to do next

Complete the medical assessment with a gastroenterologist: endoscopy with biopsy to confirm scarring and exclude a growth, testing and treatment for H. pylori, and, if there is any doubt, a gastric emptying study. Take acid suppression as prescribed and do not stop it on your own. Seek urgent care for repeated vomiting, vomiting blood or black stools, inability to keep fluids down, unexplained weight loss, or severe abdominal pain.

If the ulcer is healed and the stomach empties, ask your clinician the ATNS question directly: given that neither an active ulcer nor obstruction is present, could my symptoms be neuroplastic? If the answer is yes or maybe, start learning and practising.

This article is for general education and is not medical advice, and it does not diagnose or treat any condition. Persistent symptoms deserve a proper medical assessment to rule out disease or injury before a neuroplastic explanation is considered. If your symptoms are new, changing, or come with red-flag signs such as fever, unexplained weight loss, numbness or weakness, chest pain, or loss of bladder or bowel control, see a clinician promptly.