What Are Gallstones?

What Is the Gallbladder and What Does It Do?

Your gallbladder is a small, pear-shaped organ tucked just underneath the right side of your liver. Its job is to store bile — a digestive fluid your liver makes — and release it into your small intestine after you eat, where it helps break down fats. When you eat something fatty, your gallbladder squeezes and sends bile through a small tube called the common bile duct into your gut.

Here is something reassuring: your gallbladder is not essential. People who have it removed live completely normal lives, because bile keeps flowing directly from the liver into the intestine. But while you still have it, the bile inside can thicken and crystallise into stones — and that is where the problems can start.

What Are Gallstones Made Of?

Gallstones form when the bile stored in your gallbladder becomes too concentrated and some of its components crystallise into solid lumps. There are two main types:

Cholesterol gallstones

About 80% of gallstones in Australia are made largely of cholesterol. They form when your bile has too much cholesterol and not enough of the other substances that keep it dissolved. Over time, the cholesterol crystallises and clumps together — sometimes into one large stone, sometimes into many small ones. These stones are usually yellow or greenish.

Pigment gallstones

These form from bilirubin — a pigment released when your body breaks down old red blood cells. They tend to appear in people who have certain blood conditions (such as haemolytic anaemia — where red cells break down faster than usual) or liver cirrhosis. They are small, dark, and crumbly. Pigment stones are more common in some Asian populations.

For cholesterol stones to develop, three things need to happen at once: the bile becomes oversaturated with cholesterol, the gallbladder slows down and stops emptying properly, and the first tiny crystal forms and starts to grow. If all three happen together, stones can develop over time.

Who Gets Gallstones?

About 15–20% of Australians will develop gallstones at some point. You may have heard the old teaching of "Female, Fat, Forty, and Fertile" — and while those are real risk factors, they do not tell the whole story. Men get gallstones too, as do slim people and young adults.

Things that are known to raise your risk include:

• Being female and oestrogen exposure — oestrogen increases the amount of cholesterol secreted into bile, and progesterone slows the gallbladder down. Pregnancy, the pill, and hormone replacement therapy all add to this risk.
• Getting older — risk increases significantly after age 40.
• Being overweight, or losing weight rapidly — excess weight raises cholesterol in bile; and paradoxically, losing weight very quickly (including after weight-loss surgery) can also trigger stone formation because the gallbladder slows down.
• Family history — there is a genetic element, so if your parents or siblings had gallstones, your chances are higher.
• Diabetes and metabolic syndrome — these conditions slow gallbladder emptying, allowing bile to stagnate.
• Prolonged fasting or intravenous feeding — when you are not eating, your gallbladder does not contract and the bile sits still.
• Certain medications — including some cholesterol-lowering drugs (fibrates) and octreotide.
• Blood conditions — sickle cell disease and hereditary spherocytosis (conditions where red blood cells break down faster) are associated with pigment stones.
• Small bowel disease or surgery — conditions affecting the last part of the small bowel (the ileum) can disrupt how bile salts are recycled, making stone formation more likely.

Gallstones Without Symptoms vs Gallstones That Are Causing Problems

About two-thirds of people with gallstones never feel any symptoms at all. These are sometimes called silent gallstones — often found by chance during an ultrasound or CT scan done for a completely different reason. For most people in this situation, the risk of complications is quite low (around 1–2% per year), so watchful waiting — just keeping an eye on things — is perfectly reasonable.

But once gallstones start causing symptoms, things change. After your first episode of pain from a gallstone, the risk of further episodes or complications goes up considerably. At that point, surgery is usually the right recommendation.

How Gallstones Can Make You Feel

When gallstones cause problems, they do so in different ways depending on whether they stay in the gallbladder, move into the bile ducts, or trigger inflammation. Here is what each of those looks like.

Biliary colic — the most common type of gallstone pain

This happens when a gallstone temporarily blocks the outlet of your gallbladder — usually when the gallbladder squeezes after a meal, especially a fatty one. You feel a cramping or steady pain in the upper right side of your abdomen or the centre of your upper belly, often spreading to your right shoulder or between your shoulder blades. The pain usually builds over 15–30 minutes, peaks, lasts anywhere from half an hour to six hours, then eases off when the stone shifts back. Nausea and vomiting are common. Despite the word "colic," this pain is often more of a constant ache than a wave.

Acute cholecystitis — when the gallbladder gets inflamed

If a stone gets stuck and does not move, your gallbladder becomes blocked and then inflamed — this is called acute cholecystitis (inflammation of the gallbladder). The pain is like biliary colic but does not go away. It worsens over time, is accompanied by fever, and causes real tenderness when the right side of your abdomen is pressed. Without treatment, this can progress to pus building up inside the gallbladder, or in rare cases, a perforation. This needs prompt medical attention.

Gallstone pancreatitis — stones reaching the pancreas

Small stones or thick bile sludge can slip out of the gallbladder and get stuck at the point where the bile duct and the pancreatic duct join together. This blocks the pancreas and triggers acute pancreatitis — severe pain in your upper abdomen radiating into your back, along with nausea, vomiting, and in serious cases, very significant illness. Gallstones are actually the most common cause of acute pancreatitis in Australia.

Jaundice and bile duct infection — when stones travel further

If a stone moves into the common bile duct (choledocholithiasis — stones in the main bile duct), it can block the flow of bile from your liver. This causes jaundice — a yellowing of your skin and eyes — along with pale stools and dark urine. If the blocked duct also becomes infected (cholangitis — infection of the bile duct), you develop pain, fever with shaking chills, and jaundice all at once. This combination is a medical emergency that needs same-day treatment.

How Are Gallstones Diagnosed?

The main way to detect gallstones is with an ultrasound of your upper abdomen. It is the first test your doctor will order because it is widely available, does not involve radiation, and is very accurate — it picks up gallstones in the gallbladder more than 95% of the time. It also shows whether your gallbladder wall looks inflamed or whether the bile ducts are stretched (which can suggest a blockage).

Blood tests are also important. They help your doctor understand how your gallbladder and liver are functioning:

• Liver function tests (LFTs) — these check how your liver is working. Certain abnormal results point to a blocked bile duct; others suggest the liver itself is under stress, or that the pancreas may be involved.
• Lipase and amylase — these enzymes are released when the pancreas is inflamed. Elevated levels suggest gallstone pancreatitis.
• Full blood examination (FBE) — a raised white cell count can signal infection or inflammation in the gallbladder.
• C-reactive protein (CRP) — a general marker of inflammation that helps gauge how severe any cholecystitis might be.

If there is a suspicion that a stone has moved into the main bile duct — based on jaundice, unusual blood test results, or a stretched bile duct on ultrasound — you may need additional imaging. An MRCP (a special MRI of the bile ducts) can give a clear picture without any invasive steps. If stones in the duct are confirmed, an ERCP (a procedure using a flexible camera passed through the mouth to clear the duct) is usually performed either before or after gallbladder removal.

Treatment: Keyhole Removal of the Gallbladder

The standard treatment for symptomatic gallstones is laparoscopic cholecystectomy — keyhole surgery to remove the gallbladder. Mr Nguyen performs this operation routinely at hospitals in the Heidelberg area. It is the most effective and widely used treatment for gallstones worldwide, with a very good safety record.

During the operation:

• You are under general anaesthetic
• Three small cuts — usually 5–12 mm — are made in your abdomen
• Carbon dioxide gas is used to gently inflate your abdomen, creating space to work
• The cystic duct and cystic artery (the tubes connecting your gallbladder to the bile duct and blood supply) are carefully clipped and divided
• The gallbladder is removed through one of the small cuts
• The whole procedure usually takes about 30–60 minutes for a straightforward case

Most people go home the same day or after one night in hospital. You can usually return to light desk work within 1–2 weeks. Complications are uncommon — the most significant risk is an accidental injury to the bile duct, which occurs in fewer than 1 in 200 cases. Other possible complications include bleeding, infection, and a small bile leak. Importantly, the risk of serious complications is higher if surgery is delayed and the gallbladder becomes severely inflamed.

If stones are also found in the main bile duct, an ERCP (the duct-clearing procedure described above) is generally done either before your operation, or occasionally at the time of surgery.

Frequently Asked Questions

When to See Mr Nguyen

If you have been told you have gallstones and are getting symptoms — pain after meals, nausea, or recurring discomfort on the right side of your abdomen — it is worth having a surgical consultation. Mr Nguyen will review your scans and blood tests, confirm the diagnosis, assess your bile duct anatomy, and talk through the most appropriate plan for you.

If you have been seen in the emergency department or admitted to hospital with a complication like cholecystitis, pancreatitis, or cholangitis, a referral will usually be arranged through that team. For planned consultations, a GP referral is required — we aim to see most patients within 1–2 weeks.