A hiatus hernia means that part of your stomach has squeezed through an opening in your diaphragm and into your chest.
The stomach normally sits in the abdomen, underneath a large, thin sheet of muscle called the diaphragm (see diagram on this page).
The opening in the diaphragm that the stomach can push through is called the hiatus. Your oesophagus (tube that carries food to your stomach) passes through the hiatus to reach your stomach.
How a hiatus hernia can cause heartburn
At the base of the oesophagus is a ring-like muscle, called a sphincter, which closes the lower oesophagus. This muscle acts as a one-way valve, preventing stomach contents from flowing upwards into the oesophagus.
When part of your stomach pokes through the hiatus, it prevents the muscle from closing the lower end of the oesophagus.
This means a hiatus hernia can cause highly irritating stomach contents, such as acid, to pass up into the oesophagus. It can cause heartburn and other problems, although in many cases a hiatus hernia causes no symptoms (see Hiatus hernia - symptoms for more information).
Who is affected
Hiatus hernia can affect anyone, but it is more common in women and people who are over 50, overweight, pregnant or who smoke. It is estimated that a third of people over 50 have a hiatus hernia (see Hiatus hernia - causes for more information).
There is a rare type of hiatus hernia that affects newborn babies.
What can be done
If the hiatus hernia is not causing symptoms, treatment isn't necessary.
Symptoms of a hiatus hernia
In many cases, a hiatus hernia causes no symptoms and is discovered by chance during a routine investigation.
If you have symptoms, they can include:
- Severe heartburn and gastro-oesophageal reflux disease (GORD), where stomach acid flows back into the oesophagus.
- Deep burning chest pain, which may affect the shoulder blades. The pain is made worse by bending forward, straining or lying down. The pain may disturb sleep and can be so severe that it is mistaken for angina or a heart attack.
- Difficulty swallowing due to constant acid irritation.
Other symptoms can include a croaky voice and symptoms of asthma.
- Heartburn or indigestion is a painful, burning discomfort in the chest, usually after eating.
Causes of a hiatus hernia
The exact cause of a hiatus hernia is unknown, but some people are more at risk of developing one.
A hiatus hernia is more common in people who are:
- over 50
- overweight or obese
Pressure on the abdomen
It is thought that excessive coughing, vomiting, straining or sudden physical exertion can be contributing factors of hiatus hernia as they create extreme pressure on the abdomen.
Obesity can also cause hiatus hernia because of the increased pressure on the abdomen.
It is estimated that one-third of people over 50 have a hiatus hernia, possibly because the diaphragm gets weaker with age, allowing part of the stomach to push through it.
A rare type of hiatus hernia affects newborn babies. It occurs when the stomach or diaphragm does not develop properly.
Diagnosing a hiatus hernia
A hiatus hernia may be diagnosed after an endoscopy or an X-ray - your GP will make an appointment for you to have this done in hospital.
An endoscopy is the most common test for a hiatus hernia. An endoscope (a long, tube-like viewing instrument that contains a video camera and light source) is passed down the oesophagus (gullet) into the stomach.
If you are having an X-ray, you may swallow a watery paste made from barium sulphate. It is a heavy, odourless powder that is insoluble (does not dissolve) and is not poisonous. It coats the inside of the stomach and makes it easier to see the digestive system when an X-ray is performed.
Both procedures allow the doctor to check for evidence of a hiatus hernia.
- An X-ray is a painless way of producing pictures of inside the body using radiation.
Treating a hiatus hernia
If your hiatus hernia does not cause any symptoms, there is no need for treatment.
If you have symptoms, antacid medicines and a change of lifestyle are the preferred treatments.
Treatment aims to prevent stomach acid from flowing back into the oesophagus, improve the clearance of food from the oesophagus (gullet) and reduce the amount of stomach acid produced.
Antacid medicines can relieve some of the symptoms of hiatus hernia. Antacids come in liquid or tablet form and are swallowed or chewed. When they get to the oesophagus and stomach, they help neutralise the acid (make it less acidic).
Antacid medicines do not work for everyone. They are not a long-term solution if symptoms persist and cause extreme pain and discomfort.
Alginates contain a foaming agent, which forms a layer that floats on top of your stomach contents. This prevents stomach acid from flowing back into the oesophagus and protects your oesophagus lining.
Proton pump inhibitors
Proton pump inhibitors (PPIs) reduce the amount of acid produced by your stomach. They are usually the first treatment for gastro-oesophageal reflux disease (GORD), which can be a symptom of hiatus hernia.
Motility stimulants, such as domperidone and metoclopramide, speed up the rate at which your stomach empties. They also improve the squeezing of the sphincter muscle, to help stop stomach contents being brought back up into your oesophagus. They can cause side effects, so only take them when needed.
Surgery may be an option in some cases of hiatus hernia if medication does not relieve your symptoms. Surgery may also be recommended for cases of GORD that do not respond to other treatments.
During surgery, the stomach is put back into the correct position and the diaphragm around the lower part of the oesophagus is tightened. Surgery is commonly performed using laparoscopy (the least invasive technique, where only a small incision is made in your abdomen). See the Health A-Z topic about Laparoscopy for more information about this procedure.
The operation is not complicated and most people go home the same day.
See GORD - treatment for more information about the surgery used to treat this condition.
Complications of a hiatus hernia
Ulceration and bleeding
Acid reflux (where stomach acid flows up into the oesophagus) may cause painful damage to the oesophagus lining and can cause ulcers and, in some cases, bleeding. Loss of blood can lead to anaemia.
In rare cases, the hiatus hernia can become strangulated (knotted). This causes its blood supply to be cut off and requires emergency surgery.
Severe and long-lasting inflammation (swelling) can cause scarring and narrowing of the oesophagus. This may cause pain and can affect your ability to swallow food. This is called a stricture.
Barrett's oesophagus is a rare condition that changes the cells of the lower oesophagus, increasing the risk of cancer of the oesophagus.
There is a low risk of cancer of the oesophagus if you have long-term acid reflux.
- Acid reflux
- Acid reflux is a condition that causes heartburn. It happens when acid from the stomach flows up into the throat.
- Inflammation is the body's response to infection, irritation or injury. It causes redness, swelling, pain and sometimes a feeling of heat in the affected area.
See what the doctor sees with Map of Medicine
The Map of Medicine is used by doctors throughout the NHS to determine the best treatment options for their patients. NHS Choices offers everyone in England exclusive and free access to this cutting-edge internet resource, which lets you see exactly what your doctor sees.
The information in the Map has been approved by the UK's leading clinical experts, is based on the best available clinical evidence, and is continually updated. To take advantage of this unique resource go to: