Gallstones

Gallstones are stones that develop in your gallbladder. They are very common, but most people who have gallstones don’t get symptoms. Around 8 in 10 people with gallstones have no problems, so don’t need treatment. But if you do have issues with gallstones, such as abdominal (tummy) pain, you may need surgery.

About gallstones

Your gallbladder is a small, pear-shaped pouch in the upper right part of your tummy (abdomen). Between meals, your gallbladder stores bile, a fluid that’s produced by your liver. When you eat, your gallbladder releases bile into your bowel through a channel called the bile duct.

Bile helps your body to break down food, especially fats, and helps your body to absorb some vitamins.

Most gallstones develop when the chemicals that make up your bile become imbalanced, alongside less gallbladder motility (movement). As the bile sits, tiny crystals collect into lumps that harden, forming stones.

You might get one stone or several, and a small number of people even form dozens of stones. Gallstones also vary in size. Large stones are bigger than 1cm, but gallstones can be as small as grains of sand, or even like ‘muddy’ sludge.

If you have gallstones, they may not cause any problems. Sometimes, small gallstones may pass out of your body without you realising. In fact, most people with gallstones – around 8 in every 10 – have no symptoms. But if your gallstones begin to block the flow of bile, they can cause pain, inflammation, and infection. See our section on Gallstones Symptoms below for more information.

Types of gallstones

There are three main types of gallstones.

• Cholesterol gallstones are the most common type. These stones form if your bile has high cholesterol in it compared with other bile contents, and if this bile stagnates. Around 9 in every 10 people with gallstones have the cholesterol type.
• Pigmented gallstones are much less common – up to 15 in every 100 people with gallstones have this type. Pigmented stones form from calcium salts and bilirubin in your bile. Bilirubin is a waste product of your body breaking down red blood cells.
• Mixed gallstones are made up of both cholesterol and pigment.

Causes of gallstones

You’re more likely to get gallstones as your age increases, especially after 40. Women are more than twice as likely to get gallstones as men. If you have someone in your family with gallstones, this also makes stones more likely for you. Some genes have been linked to gallstones too.

Your chances of gallstones are also higher if you:

• have obesity, diabetes, or metabolic syndrome
• have high cholesterol
• are pregnant
• take hormone replacement therapy (HRT)
• have non-alcoholic fatty liver disease (NAFLD)
• have fasted for a long time, or lost weight quickly – for example, through weight loss surgery
• take certain medicines
• have Crohn’s disease
• have a hereditary blood disorder (one passed down through parents) like sickle cell anaemia

Diet and physical activity

A diet high in protein and fibre, calcium, and vitamin C might help, along with physical activity, to prevent gallstones forming.

The evidence about diet directly causing gallstones, though, is weak. Eating foods high in fat and sugars, and other refined carbohydrates, along with foods that are low in fibre has, however, been linked to getting gallstones.

Conversely, eating a high-fibre diet with plenty of fruits and vegetables has been connected to a lower chance of gallstones. Also, obesity, diabetes, and metabolic syndrome are known risk factors behind gallstones. A healthy diet and physical activity can help against these conditions.

If you already have gallstones, you may notice that some foods trigger symptoms, so it’s best to avoid or cut back on these. Your doctor may recommend you eat a low-fat diet to help to prevent the pain from gallstones, although the scientific evidence for this is not strong.

Symptoms of gallstones

Most people with gallstones – around 8 in every 10 people – don’t have any symptoms. Sometimes, gallstones are found if you have a scan for something else.

Abdominal pain (biliary colic)

The most common gallstones symptom is pain in part of your abdomen (tummy). This is usually in the upper part of your tummy, just under your ribs, and in the middle or to the right side.

This pain is known as biliary colic, and it usually feels severe. The pain may spread to the right side of your back or your right shoulder.

This pain of biliary colic is caused by the squeezing action of the gallbladder around gallstones. This can happen when they block the flow of bile out of your gallbladder.

You may develop this pain about an hour after a heavy meal, and you may notice this gallstones symptom in the evening.

The pain comes on suddenly, then it’s steady and usually lasts for at least 30 minutes. It may go on for up to eight hours, but usually starts to go away before this. You can still have a dull ache after the pain has gone. You may also feel sick and be sick (vomit).

Other less common gallstones symptoms

Gallstones may block the flow of bile for a long time, and may leave your gallbladder and cause problems in your bile duct or pancreas. See our section on Complications below for more information about what can happen.

If you get a complication of gallstones, the symptoms may then include the following.

• A high temperature, perhaps with shivering and ‘chills’ or shaking (rigours).
• Pain that doesn’t go away.
• Tenderness when pressing on your tummy.
• Yellow skin and a yellowing of the whites of your eyes (jaundice).
• Dark pee and pale poo.
• Itchy skin.

Diagnosis of gallstones

It might be that you don’t have gallstones symptoms and discover you have gallstones only after a test for some other reason. This could be when you go for an ultrasound of your abdomen (tummy).

If you do have gallstones symptoms, your GP will ask about these and your medical history. This will help to identify possible causes and any other conditions. They’ll feel your tummy area to see if it’s tender or swollen.

You may need blood tests to check for any inflammation or infection, a problem with your liver, or a blocked bile duct.

Your GP may refer you to your local hospital for more tests. Some of these are described below. You may have to go to hospital straightaway if your GP thinks you have complications needing immediate treatment.

• An ultrasound scan – this uses sound waves to produce an image of the inside of your body. Gallstones usually show up well on this type of scan. Very small stones may be missed, though.
• A type of MRI scan, called a magnetic resonance cholangiopancreatography (MRCP) – this can produce images of the inside of your body, including your pancreatic and bile ducts.
• An endoscopic ultrasound scan – this may be an option if you can’t have an MRCP for some reason. A narrow, flexible, tube-like telescopic camera called an endoscope goes down through your mouth and stomach. It can spot small gallstones lying in your bile duct.
• A CT scan – this can produce detailed images of your bile ducts, liver, and pancreas.

If you have an ultrasound and MRCP, you will need to eat no food for six hours before the scan. This allows the gallbladder to fill up with bile and give better images.

Complications of gallstones

Most gallstones do not cause any symptoms or problems. But sometimes they can cause complications. They may block ducts to your internal organs like your gallbladder, liver, pancreas, and small intestine. This may cause inflammation, swelling, or infection.

The following two are among the most common complications of having gallstones.

• Biliary colic. This is a type of pain, and it’s the most common problem for people who get symptoms with gallstones. Your gallstones can be painful when your gallbladder or duct (connecting tube) tightens around them. See our section on Gallstones symptoms above for more information about biliary colic.
• Cholecystitis. This is an inflamed gallbladder and the second most common complication. It can lead to a severe infection, and damage to your gallbladder. If you have an infection, you’ll need antibiotics. You’ll usually have these intravenously (into a vein) in hospital.

Other complications are much less common but can be more harmful. These include the following.

• Jaundice. If gallstones pass out of your gallbladder and block your bile duct, the flow of bile may stop. This will make your skin and eyes look yellow.
• Pancreatitis. Gallstones may travel down your bile duct and block the duct from your pancreas. This causes inflammation in your pancreas, which is a serious medical condition.
• Cholangitis. Your bile duct may get infected if a gallstone completely blocks it. This needs urgent treatment.
• Gallstone ileus. This is an obstruction in your bowel that can happen with gallstones, but only rarely. If large gallstones pass out of your gallbladder, they might block your bowel.
• Gallbladder cancer. Rarely, people with gallstones develop gallbladder cancer. But there is no evidence that gallstones themselves cause cancer.

Your doctor will explain any tests and treatments you might need if you have a complication of gallstones.