Stomach pain is one of the most common reasons Australians look for medical help after hours, and most of the time it settles on its own within a day or two. The tricky part is knowing which stomach ache is harmless and which one needs a doctor tonight. Where the pain sits, how quickly it came on, and what else is happening alongside it usually tell you more than the pain itself.

This guide walks through the usual causes of upper, lower and right-sided stomach pain, explains what causes stomach ulcers, and sets out the warning signs that mean you should stop reading and call for help.

If the pain is sudden and severe, call 000 immediately.

What people mean by "stomach pain"

Medically, stomach pain usually means abdominal pain - any discomfort felt between the bottom of your ribs and your pelvis. Your actual stomach is only one organ in that space. The same area also holds your liver, gallbladder, pancreas, bowel, kidneys, bladder and reproductive organs, which is why a "sore stomach" can come from so many different places.

The pain might be cramping, burning, stabbing, dull or twisting. It can arrive in waves, sit constantly in one spot, or shift over a few hours. None of those descriptions is automatically more serious than another, but they do help a doctor narrow things down.

For a general overview of how doctors assess this symptom, the Victorian Department of Health's Better Health Channel guide to abdominal pain in adults explains the questions clinicians work through.

Upper stomach pain: what's usually behind it

Upper stomach pain - felt below the breastbone and above the belly button - most often comes from the stomach itself, the oesophagus, the gallbladder or the pancreas.

The common culprits include:

Indigestion and reflux. A burning discomfort that creeps up towards the chest, often worse after a large or fatty meal, or when lying down.
Gastritis. Inflammation of the stomach lining, which can follow an infection, heavy alcohol use, or regular anti-inflammatory tablets.
Peptic ulcers. A gnawing or burning pain in the centre of the upper abdomen that may ease briefly after eating, then return.
Gallstones. Intense pain in the upper right area, sometimes spreading to the right shoulder blade, and often triggered after eating.
Pancreatitis. A severe, boring pain that bores through to the back and usually comes with vomiting. This one needs urgent assessment.

Upper stomach pain that arrives with chest tightness, shortness of breath, sweating or pain spreading into the jaw or arm should never be treated as indigestion. Call 000.

Lower stomach pain: common causes

Lower stomach pain sits below the belly button, and the shortlist changes depending on what else is going on.

Constipation and trapped wind are far and away the most frequent reasons - uncomfortable, sometimes surprisingly sharp, and usually short-lived. Gastroenteritis brings cramping lower stomach pain alongside diarrhoea and vomiting. A urinary tract infection tends to cause a lower, central ache with burning when you pass urine and a constant urge to go.

Period pain, ovulation pain and endometriosis cause cyclical lower stomach pain, and irritable bowel syndrome produces cramping that eases after a bowel motion. Appendicitis often starts as a vague ache around the belly button before settling firmly into the lower right side over several hours.

If lower stomach pain comes with fever, or if you're pregnant and have pain or bleeding, that needs same-day medical assessment rather than watchful waiting. A telehealth GP consultation is a reasonable first step when you are unsure whether the symptoms warrant a trip to hospital.

Stomach pain and right side symptoms

Pain in the right side of the stomach deserves its own mention because two of the causes are time-sensitive.

In the upper right, the gallbladder is the usual suspect. Gallstone pain builds over minutes, sits hard under the right ribs, and can radiate to the right shoulder or the back. It may last anywhere from twenty minutes to several hours. Liver inflammation can produce a duller ache in the same region, sometimes with yellowing of the skin or eyes.

In the lower right, appendicitis is the one nobody wants to miss. The classic pattern is pain that begins near the navel and migrates right and low over six to twenty-four hours, worsens when you move, cough or press on the area, and comes with nausea and a low-grade fever. It does not improve with rest.

Kidney stones cause a different kind of right-sided pain - severe, coming in waves, felt more towards the back and flank, and often radiating down into the groin.

Right-sided stomach pain that is worsening rather than settling, or that stops you walking upright, should be assessed in person. Depending on where you are and what time it is, a home doctor visit may be appropriate, though anything severe belongs at an emergency department.

What causes stomach ulcers?

Stomach ulcers are open sores in the stomach lining, and the two causes that account for the overwhelming majority are infection with Helicobacter pylori bacteria and long-term use of non-steroidal anti-inflammatory medicines such as ibuprofen, naproxen and aspirin. Ulcers in the first part of the small intestine are called duodenal ulcers; together the two are known as peptic ulcers.

The older belief that spicy food and stress cause ulcers has not held up. Both can aggravate the symptoms of an ulcer that already exists, and smoking and heavy alcohol use raise the risk, but they are not the underlying cause.

Typical ulcer pain is burning or gnawing, sits in the upper abdomen, and comes and goes rather than staying constant. It often wakes people during the night. Some people notice it eases after eating; others find eating makes it worse. Bloating, nausea and feeling uncomfortably full after small meals are common companions.

Ulcers are treatable, and testing for H. pylori is straightforward. Healthdirect's clinical information on stomach ulcers and their causes covers diagnosis and treatment in more detail. What matters most is not leaving it - an untreated ulcer can bleed or perforate.

Red flags: when stomach pain is an emergency

Call 000 or go straight to your nearest emergency department if stomach pain comes with any of the following:

Sudden, severe pain that stops you doing anything else
Vomiting blood, or vomit that looks like coffee grounds
Black, tarry or bloody bowel motions
A rigid abdomen that is painful to touch
Chest pain, shortness of breath, sweating, or feeling pale and clammy
Pain with vaginal bleeding during pregnancy
Inability to pass urine, open your bowels or pass wind
High fever with severe pain
Pain that spreads to the chest, neck or shoulder

These are not symptoms to sleep on or wait out until morning.

Managing a mild stomach ache at home

If the pain is mild, you have no red flags, and you're otherwise well, a short period of self-care is reasonable.

Sip clear fluids regularly rather than drinking large amounts at once. Stick to plain, simple food and give fatty, spicy or very rich meals a miss for a day or two. Rest, and use a heat pack for cramping if it helps. Avoid anti-inflammatory tablets, since they can irritate the stomach lining and make things worse - paracetamol is usually the gentler option for general pain.

Keep an eye on the pattern. Pain that is improving hour by hour is reassuring. Pain that is the same or worse after twenty-four hours, or that keeps returning over several weeks, should be reviewed by a doctor.

Getting medical advice after hours

Stomach pain has an unhelpful habit of flaring up in the evening, on a weekend, or on a public holiday, when your regular clinic is closed. 13CURE exists for exactly that gap - after-hours urgent care for non-life-threatening concerns, delivered either at home or by phone and video.

Bookings are taken Monday to Friday from 6pm through to 8am, Saturdays from 12pm, and 24 hours on Sundays and public holidays. For eligible Medicare and DVA cardholders, consultations are bulk billed, with no out-of-pocket cost - the bulk billing GP page explains eligibility in full.

If travelling isn't practical, a bulk billed telehealth appointment lets an AHPRA-registered GP assess your symptoms from wherever you are. Whether a home visit is available will depend on your location and doctor availability, which you can check against our areas we cover.

When you're ready, you can book a home doctor visit online or call 13CURE (132873).

13CURE: Your Questions Answered - Everything You Need to Know!

Most mild stomach aches settle within twenty-four to forty-eight hours. Pain that persists beyond two days, keeps coming back over several weeks, or steadily worsens rather than easing should be assessed by a GP.

Stress and anxiety can genuinely produce stomach cramps, nausea and changes in bowel habits through the gut-brain connection. That said, stress should be a diagnosis of exclusion - it's worth having persistent pain checked rather than assuming.

Severity, speed of onset and accompanying symptoms are the useful markers. A stomach ache that is mild, improving, and unaccompanied by fever, bleeding or vomiting is usually benign. Sudden severe pain, or pain with any of the red flags listed above, is not.

No. The gallbladder, pancreas, liver and even the heart and lungs can all produce pain felt in the upper abdomen. This is one reason upper stomach pain with chest symptoms is treated as urgent.

A GP may prescribe medication if it is clinically appropriate after assessing you. Nothing is guaranteed in advance - the decision rests with the doctor based on your symptoms and history.

Recurrence is usually down to an H. pylori infection that wasn't fully cleared, or continued use of anti-inflammatory medicines. Discuss both with your GP if symptoms return after treatment.