Acute pancreatitis causes sudden severe abdominal pain and usually needs hospital care. Most attacks are mild and settle within a week. Finding and treating the cause, especially gallstones, alcohol and high blood fats, is the key to preventing another attack.

What is it?

The pancreas lies behind the stomach. It makes digestive enzymes and hormones such as insulin. In acute pancreatitis, the enzymes become active inside the pancreas itself, causing inflammation. Most attacks are mild and the pancreas recovers fully. A smaller number are severe, with damage to the pancreas or effects on other organs, and need longer hospital care.

Common causes

• Gallstones: a small stone blocks the outlet of the pancreatic duct. This is one of the commonest causes
• Alcohol
• Very high triglycerides (a type of blood fat), usually above about 11 mmol/L (1,000 mg/dL), often linked to poorly controlled diabetes, pregnancy or inherited lipid disorders
• Some medicines, including azathioprine, which is used in IBD; this usually happens in the first weeks of treatment
• After ERCP, a known complication of this procedure
• Less common: high calcium, abdominal injury, some pancreatic cysts or tumours, and inherited causes
• Sometimes no cause is found despite full testing

Symptoms and diagnosis

• Sudden, severe pain in the upper abdomen, often spreading to the back, and sometimes eased by sitting forward
• Nausea and vomiting
• Fever and a fast heartbeat in some people
• Diagnosis is made from the typical pain and a blood test showing a marked rise (usually more than three times normal) in pancreatic enzymes (lipase or amylase). An ultrasound looks for gallstones. A CT scan is not needed in most people at the start; it is used if the diagnosis is uncertain or the patient is not improving

Care in hospital

• Fluids into a vein, given in measured amounts and adjusted to your needs
• Good pain relief, which may include strong painkillers
• Eating: you can usually start eating as soon as the pain and nausea allow, often within a day or two, beginning with light, low-fat food. Early eating helps recovery. If you cannot eat for longer, nutrition may be given through a feeding tube
• Antibiotics are not needed routinely; they are used only if there is a proven infection
• Severe attacks are cared for in a high-dependency or intensive care unit. Areas of damaged pancreas or fluid collections usually settle; some need drainage later, often endoscopically

Preventing another attack

• Gallstones: removing the gallbladder is recommended. After a mild attack, this is best done during the same admission or very soon after, because attacks often recur while waiting. After a severe attack, the operation is usually delayed until you have recovered; your team will plan the timing
• Alcohol: stopping completely is the most effective step. Support is available, and asking for it is a sign of strength
• Smoking: stop, as it increases the risk of further attacks and of chronic pancreatitis
• High triglycerides: diet, weight loss, good diabetes control and lipid-lowering medicines
• Medicines: a medicine that caused pancreatitis should not be restarted
• If no cause is found, further tests such as endoscopic ultrasound (EUS) or MRI may be advised, especially after age 40

After you go home

Most people recover fully. Return to a normal balanced diet; very fatty meals may be uncomfortable at first. About 1 in 5 people develop diabetes in the years after an attack, and some develop poor digestion of fat, especially after a severe attack, so your blood sugar (HbA1c) should be checked about once a year during follow-up. Report oily, pale stools or weight loss.

Common questions

This leaflet is general information and does not replace advice from your own doctor. Version 1.0, October 2026. Next review October 2028.