A gastrectomy is a medical procedure where all or part of the stomach is surgically removed.

When a gastrectomy is needed

A gastrectomy is often used to treat stomach cancer.

Less commonly, it's used to treat:

  • life-threatening obesity
  • oesophageal cancer
  • stomach ulcers (peptic ulcers)
  • non-cancerous tumours

Gastrectomy is usually an effective treatment for cancer and obesity.

How a gastrectomy is performed

There are four main types of gastrectomy, depending on which part of your stomach needs to be removed:

  • total gastrectomy – the whole stomach is removed
  • partial gastrectomy – the lower part of the stomach is removed
  • sleeve gastrectomy – the left side of the stomach is removed
  • oesophagogastrectomy – the top part of the stomach and part of the oesophagus (gullet), the tube connecting your throat to your stomach, is removed

The top of the stomach is connected to the gullet, the bottom of the first part of the small intestine (duodenum), and the gullet to either the small intestine or the remaining section of stomach. This means that you'll still have a working digestive system, although it won't function as well as it did before.

All types of gastrectomy are carried out under general anaesthetic, so you'll be asleep during the operation.

Techniques for gastrectomy

Two different techniques can be used to carry out a gastrectomy:

  • open gastrectomy - where a large cut is made in your stomach or chest
  • keyhole surgery (laparoscopic gastrectomy) - where several smaller cuts are made and special surgical instruments are used

People who have keyhole surgery usually recover faster and have less pain after the procedure than those who have an open gastrectomy. You may also be able to leave hospital a little sooner.

Complication rates after keyhole surgery are similar to those for open gastrectomies.

Open gastrectomies are usually more effective in treating advanced stomach cancer than keyhole surgery is. This is because it's usually easier to remove affected lymph nodes (small glands that are part of the immune system) during an open gastrectomy.

Before you decide which procedure to have, discuss the advantages and disadvantages of both with your surgeon.

Recovering after a gastrectomy

A gastrectomy is a major operation, so recovery can take a long time. You'll usually stay in hospital for one or two weeks after the procedure, where you may receive nutrition into a vein until you can eat and drink again.

You'll eventually be able to digest most foods and liquids. However, you may need to make changes to your diet, such as eating frequent small meals instead of 3 large meals a day. You may also need vitamin supplements to ensure you're getting the correct nutrition.

Read more about recovering from a gastrectomy.


As with any type of surgery, a gastrectomy carries a risk of complications, such as infection, bleeding and leaking from the area that's been stitched together.

A gastrectomy may also lead to problems caused by a reduction in your ability to absorb vitamins, such as anaemia and osteoporosis.

Read more about the possible complications of a gastrectomy.


A gastrectomy is a serious operation, and recovery can take a long time.

After the operation

After having a gastrectomy, you may be fitted with a nasogastric tube for about 48 hours. This is a thin tube that passes through your nose and down into your stomach or small intestine. It allows fluids produced by your stomach to be regularly removed, which will stop you feeling sick.

You'll also have a catheter placed in your bladder. This is to monitor your fluids, and to drain and collect urine while you recover.

Until you can eat and drink normally, nutrition will be given directly into a vein (intravenously) or through a tube inserted through your tummy into your bowel. Most people can begin eating a light diet about a week after having a gastrectomy.

After the operation, you'll need to take regular painkillers until you recover. Tell your treatment team if the painkillers you're taking don't work - alternative painkillers are available.

You'll probably be able to return home one to two weeks after having a gastrectomy.

Adjusting to a new diet

Whatever type of gastrectomy you have, you'll need to make changes to your diet. It may be months before you can return to a more normal diet. A dietitian should be able to help you with this adjustment.

Food or drink you enjoyed before the operation may give you indigestion. You may find it helpful to keep a food diary to record the effects that certain types of food have on your digestion.

You'll probably have to eat frequent small meals, rather than 3 large meals a day, for a fairly long time after having a gastrectomy. However, over time your remaining stomach and small intestine will stretch and you'll gradually be able to eat larger, less frequent meals.

The Oesophageal Patients Association (OPA) has produced a guide to life after stomach surgery (PDF, 605kb), containing lifestyle advice for people after they've had a gastrectomy.

High-fibre foods

Avoid eating high-fibre foods immediately after having a gastrectomy, as they'll make you feel uncomfortably full. High-fibre foods include:

  • wholegrain bread, rice and pasta
  • pulses – which are edible seeds that grow in a pod, such as peas, beans and lentils
  • oats – found in some breakfast cereals

You'll gradually be able to increase the amount of fibre in your diet.

Vitamins and minerals

If you've had a partial gastrectomy, you may be able to get enough vitamins and minerals from your diet by eating foods that are high in nutrients - in particular, foods high in iron, calcium, and vitamins C and D. If you've had a total gastrectomy, you may be unable to get enough of these from your diet so may require supplements.

Read about vitamins and minerals for information on foods that are high in these nutrients.

Most people who have had a total gastrectomy, and some who have had a partial gastrectomy, need regular injections of vitamin B12 because this is difficult to absorb from food if your stomach has been removed.

After a gastrectomy, you'll need regular blood tests to check you're getting the right amount of vitamins and minerals in your diet. Incorrect nutrition can lead to problems such as anaemia.


As with any type of surgery, a gastrectomy carries a risk of complications. Problems can also occur because of changes in the way you digest food.

Gastrectomy to treat cancer

Gastrectomies to treat stomach cancer carry a higher risk of complications, because most people who have this type of surgery are elderly and often in poor health.

Complications can also occur after a gastrectomy to treat oesophageal cancer. The oesophagus, also called the gullet, is the tube connecting your throat to your stomach.

Possible complications of a gastrectomy include:

  • wound infection
  • leaking from a join made during surgery
  • stricture – where stomach acid leaks up into your oesophagus and causes scarring, leading to the oesophagus becoming narrow and constricted over time
  • chest infection
  • internal bleeding
  • blockage of the small intestine

An infection can usually be treated with antibiotics, but some other complications will require further surgery. Before your operation, ask your surgeon to explain the possible risks and how likely they are.

Gastrectomy to treat obesity

Possible complications of a gastrectomy for obesity include:

  • nausea and vomiting – which usually get better over time
  • internal bleeding
  • blood clots
  • leaking from where the stomach has been closed
  • acid reflux – where stomach acid leaks back up into the oesophagus
  • infection

It may be possible to treat some complications with medication, but others may need further surgery. Before your operation, ask your surgeon to explain the possible risks and how likely they are to affect you.

Vitamin deficiency

One of the stomach's function is to absorb vitamins - particularly vitamins B12, C and D - from the food you eat.

If your entire stomach has been removed, you may not get all the vitamins your body needs from your diet. This could lead to health conditions such as:

  • anaemia
  • increase vulnerability to infection
  • brittle bones (osteoporosis) and weakened muscles

Changing your diet may help to compensate for your stomach's inability to absorb vitamins. However, you may need vitamin supplements even after changing your diet. The healthcare professionals treating you can advise on this.

Read about recovering from a gastrectomy for more information on diet and supplements.

Weight loss

Immediately after surgery, you may find that even eating a small meal makes you feel uncomfortably full. This could lead to weight loss.

Losing weight may be desirable if you've had a gastrectomy because you're obese, but it can be a health risk if you've been treated for cancer.

Some people who have a gastrectomy regain weight once they have adjusted to the effects of surgery and have changed their diet. But if you continue to lose weight, see a dietitian. They can give you advice on how to gain weight without upsetting your digestive system.

Dumping syndrome

Dumping syndrome is a set of symptoms that can affect people after a gastrectomy. It's caused when particularly sugary or starchy food moves suddenly into your small intestine.

Before a gastrectomy, your stomach digested most of the sugar and starch. However, after surgery, your small intestine has to draw in water from the rest of your body to help break down the food.

The amount of water that enters your small intestine can be as much as 1.5 litres (3 pints). Much of the extra water is taken from your blood, which means you experience a sudden fall in blood pressure. The drop in blood pressure can cause symptoms such as:

  • faintness
  • sweating
  • palpitations
  • a need to lie down

The extra water in your small intestine will cause symptoms such as:

If you have dumping syndrome, resting for 20 to 45 minutes after eating a meal may help. To ease the symptoms of dumping syndrome:

  • eat slowly
  • avoid sugary foods - such as cakes, chocolate and sweets
  • slowly add more fibre to your diet
  • avoid soup and other liquid foods
  • eat smaller, more frequent meals

Seek advice from your hospital team or dietitian if you have symptoms of dumping syndrome. For most people, the symptoms improve over time.

Morning vomiting

After a partial gastrectomy, a small number of people may experience morning vomiting.

Vomiting occurs when bile - a fluid used by the digestive system to break down fats - and digestive juices build up in the first part of your small intestine (duodenum) overnight, before moving into what remains of your stomach.

Because of its reduced size, your stomach is likely to feel uncomfortably full, triggering a vomiting reflex to get rid of the excess fluids and bile.

Taking indigestion medication, such as aluminium hydrozide, may help to reduce the symptoms of morning vomiting. See your GP if your symptoms are particularly troublesome.


During a gastrectomy, it's sometimes necessary to cut a nerve called the vagus nerve, causing many people to experience bouts of diarrhoea. The vagus nerve helps to control the movement of food through your digestive system.

Speak to your doctor or nurse if you have diarrhoea, as treatments are available.

The information on this page has been adapted by NHS Wales from original content supplied by NHS UK NHS website
Last Updated: 22/06/2023 14:22:24