Gastroparesis: symptoms, causes, diet and treatment

The NHS says symptoms start after eating and may include feeling full sooner than usual, so you cannot finish meals, feeling sick (nausea) and being sick (vomiting), tummy pain, heartburn and bloating. If you have had these symptoms for a while, you may also be losing weight. Guts UK adds belching, and says symptoms can also happen between meals or at night.

Guts UK says symptoms range from mild to severe, usually occur in combination rather than alone, and would usually be present for three months or more. Being sick repeatedly can lead to dehydration, and some people experience malnutrition and weight loss. Severe symptoms that cause dehydration and severe malnutrition may need a hospital stay. Long-term symptoms can also affect quality of life and mood, and Guts UK says to discuss low mood with your doctor.

• Feeling full after a few mouthfuls, or being unable to finish a normal-sized meal.

• Nausea and vomiting.

• Tummy pain and bloating.

• Heartburn and belching.

• Weight loss, if symptoms have gone on for a while.

The NHS lists when to seek help for symptoms of gastroparesis or a similar condition. The symptoms could also point to another condition, so it is important to get them checked.

The NHS describes gastroparesis as a long-term condition that can be managed with diet changes, medicines and other treatments. Diet is usually the starting point (see the diet section below). The NHS says you may be referred to a dietitian to make sure you get enough nutrients.

Medicines can help food move through your stomach faster, stop you feeling or being sick, and help with pain. Guts UK mentions domperidone, which can cause problems with the heart rhythm in susceptible people and is best avoided if you have a known heart problem, and says a doctor may consider prucalopride, which is used off-label (it is not listed in the British National Formulary for gastroparesis) when there are few choices.

If your gastroparesis is linked to diabetes, the NHS says you may be offered ways to manage blood sugar, such as an insulin pump. Guts UK explains that keeping blood sugar normal matters in diabetic gastroparesis, and that for type 1 diabetes NICE guidance suggests considering an insulin pump. Guts UK also says opioid-based medicines slow the stomach even more, so a doctor may suggest stopping them. Never stop a medicine without discussing it with your doctor.

Depending on your symptoms, other treatments may be offered. Guts UK says the more invasive options below have limited research evidence, carry greater risks, are not widely available and need careful consideration.

The name means stomach paralysis, although the stomach is not literally paralysed. Normally the muscular wall of the stomach churns food and pushes it through the valve at its lower end into the small intestine. In gastroparesis that action is weak or poorly coordinated, so the stomach empties slowly even though there is no blockage.

Guts UK describes it as a chronic disorder that can affect people of all ages and that tends to fluctuate. Symptoms are usually present for three months or more before the diagnosis is made. It is also not unusual for gastroparesis to overlap with functional dyspepsia, a condition with similar symptoms but generally less nausea and vomiting and more pain, and some people move between the two.

The NHS says gastroparesis is thought to be a problem with the nerves and muscles of the stomach and that the cause is not always known. It can be a complication of long-term conditions such as diabetes, where persistently high blood sugar can damage the stomach nerves over time, and it can follow some types of surgery.

Guts UK lists neurological conditions such as multiple sclerosis and Parkinson's disease, connective tissue disease such as systemic sclerosis, and surgery on the oesophagus, for reflux (fundoplication), gastric bypass, part-stomach removal, vagus nerve cutting, lung or pancreatic surgery. It says gastroparesis may follow a stomach infection, although this is not proven, and that medicines, in particular opioid-based painkillers, can cause or worsen it.

In children, Guts UK says idiopathic gastroparesis is the most common type, with medication the second most common cause. It also notes that people with eating disorders can experience delayed stomach emptying, and recommends speaking to a doctor if that is a concern.

The NHS says diet changes may be recommended: eating 4 to 6 small meals a day rather than 3 large meals, reducing insoluble fibre (the type that cannot be digested, for example wholegrain bread, beans and some vegetables and fruits), and, for some people, a liquid diet such as soups or meals blended in a food processor.

Guts UK says dietary changes may help control symptoms but there is no single "gastroparesis diet". It adds the practical points below, and strongly advises making major changes, such as a smooth or liquid diet, with a trained and registered dietitian so that the diet still provides the nutrients you need.

• Chew food well; this gives a better texture and helps stomach emptying.

• Avoid tough fibrous foods, such as raw vegetables, citrus fruits, celery, pumpkin, grapes, prunes and raisins, which empty slowly and may form a compact mass called a bezoar.

• Avoid fizzy drinks, which may increase bloating.

• Large meals are often poorly tolerated; six small meals, or three small meals and three snacks, can reduce symptoms and help maintain weight.

• Lower-fat diets can reduce symptoms but could make malnutrition worse, so ask for a dietitian referral first.

• Dietitians may offer nutrition drinks, which provide calories and nutrients without solid meals.

The NHS says people with symptoms usually have blood tests and an X-ray or ultrasound scan of the stomach to rule out other conditions first. If these are unrevealing, a gastroscopy and tests to measure how long food takes to leave the stomach may follow.

Guts UK describes the main emptying tests. In gastric emptying scintigraphy you eat a meal, usually scrambled egg with bread, that contains a small amount of a short-lived radioactive tracer, and gamma cameras follow its progress. In a breath test you eat a food containing a substance that is absorbed in the small bowel and later appears in your breath, and samples are collected over a few hours.

Some medicines, notably opioids such as codeine, tramadol and morphine, affect test results and may need to be paused beforehand, but only on a doctor's advice. Guts UK adds that an abnormal result does not always mean gastroparesis, because the same findings can occur in functional dyspepsia and the relationship between results and symptoms is not exact.

The NHS calls gastroparesis a long-term condition. Guts UK says it can improve for some people over time (at least 12 months), particularly those whose gastroparesis followed an infection. For others it persists, and treatment focuses on controlling symptoms and protecting nutrition.

Your doctor will check your symptoms and weight to see whether treatment is working, and other options can be tried if moderate to severe symptoms continue. Guts UK says that if you need a feeding tube, it is usually suitable for home feeding once you or a carer have been trained.

On the NHS, gastroparesis is usually first assessed by a GP, then a gastroenterologist for gastroscopy and emptying tests, with a dietitian and, where relevant, a diabetes team. Treatments such as a gastric electrical stimulator are not routinely funded, according to Guts UK.

A private gastroenterologist may be able to arrange the gastroscopy and gastric emptying study sooner and give you more time to talk through options. The tests themselves are the same and some are only available in specialist centres in either sector, so it is worth asking where a scan or procedure would actually be performed and who would manage follow-up and feeding support.