Acute pancreatitis
Confirm it with lipase or amylase, give moderate IV fluids guided by the patient, good pain relief, feed early, find the cause, and score the severity. No routine antibiotics.
A 45-year-old woman with known gallstones has severe epigastric pain going through to her back, with vomiting, since a heavy meal last night. Pulse 112, BP 108/70. Lipase is 8 times the upper limit of normal.
How much fluid, what pain relief, and does she need antibiotics?
- Resuscitate with IV fluidsRinger's lactate, moderate amounts, guided by pulse, BP and urine output.
- Pain reliefStrong analgesia, usually opioids, with an antiemetic.
- Oxygen if SpO₂ is lowWatch for breathing problems (ARDS).
- BloodsCBC, urea, creatinine, electrolytes, calcium, sugar, LFTs, lipase, CRP, gas with lactate, triglycerides.
- Ultrasound for gallstonesWithin 24 hours.
- Catheter and hourly urineIf unwell.
- Feed earlyBy mouth as soon as tolerated, usually within 24–72 hours.
- Score the severityGlasgow-Imrie within 48 hours.
- Organ failure: low BP, low oxygen, rising creatinine
- Glasgow-Imrie 3 or more
- Rigors, jaundice, deranged LFTs (cholangitis)
- Rising lactate
- Rigid abdomen
- Severe pancreatitis
- Cholangitis with gallstone pancreatitis
- Infected necrosis
- Perforated ulcer, ruptured AAA, MI or mesenteric ischaemia (can also raise amylase)
| Diagnosis | 2 of 3: typical pain, lipase or amylase above 3 times normal, imaging changes |
| Fluids | Moderate: Ringer's lactate 10 mL/kg bolus if dry, then about 1.5 mL/kg/hour, adjusted to the patient |
| Urine target | At least 0.5 mL/kg/hour |
| Antibiotics | Not routinely. Only for proven infection (cholangitis, infected necrosis, other source) |
| Glasgow-Imrie 3 or more | Severe: HDU review |
Check every dose against a current drug reference and your hospital protocol.
On this page
What it is
The pancreas becomes inflamed when its own digestive enzymes are activated inside it. Most cases are mild and settle in a few days. A minority become severe, with organ failure and dead (necrotic) pancreas, and these patients can die.
- Gallstones (the commonest cause in Pakistan) and ethanol (alcohol).
- Idiopathic, trauma, steroids, mumps and other infections, autoimmune, scorpion sting, high calcium, high triglycerides, after ERCP, and drugs (azathioprine, valproate, thiazides, and others).
Diagnosis
- Typical pain: severe, constant epigastric pain often going through to the back.
- Lipase (or amylase) more than 3 times the upper limit of normal.
- Changes on imaging (CT, MRI or ultrasound).
- Do not repeat lipase or amylase daily. The level does not show severity or progress.
- CT is not needed in the first 72 hours unless the diagnosis is uncertain. Early CT underestimates necrosis.
- Amylase can also rise in a perforated ulcer, mesenteric ischaemia, ruptured AAA and DKA. If the patient looks worse than expected, think again.
Severity
- PaO₂ below 60 mmHg (8 kPa)
- Age over 55
- Neutrophils (white count) above 15,000/µL
- Calcium below 2 mmol/L (8 mg/dL)
- Renal: urea above 16 mmol/L (96 mg/dL)
- Enzymes: LDH above 600 units/L or AST above 200 units/L
- Albumin below 32 g/L (3.2 g/dL)
- Sugar above 10 mmol/L (180 mg/dL)
3 or more = severe: HDU or ICU review.
- Organ failure is what defines severe pancreatitis: low BP, low oxygen, kidney injury. Persistent organ failure beyond 48 hours carries the highest risk.
- CRP above 150 mg/L at 48 hours also suggests severe disease.
Fluids: not too little, not too much
The old practice of giving very large volumes has changed. The WATERFALL trial (2022) found that aggressive fluids caused more fluid overload without improving outcomes.
- Pulse and BPImproving pulse and BP: continue and reduce as able.
- Urine outputAim for at least 0.5 mL/kg/hour.
- Chest and SpO₂New crackles or falling SpO₂: slow fluids, senior review.
- BloodsUrea, creatinine and haematocrit trends.
Pain and nausea
Feeding
- Feed early. Start eating as soon as the patient is hungry and the pain and vomiting allow, usually within 24–72 hours. A low-fat diet is fine.
- Can't eat after a few days? Enteral feeding by NG or nasojejunal tube is better than IV nutrition.
- Prolonged "nil by mouth" to "rest the pancreas" is not recommended.
Antibiotics
Antibiotics do not prevent infection of the pancreas and are not given just because pancreatitis is severe.
Give antibiotics only for:
- Cholangitis (fever, jaundice, right upper quadrant pain): antibiotics and urgent ERCP.
- Infected necrosis (usually after the first week: new fever, worsening, gas in the necrosis on CT).
- Another proven infection (chest, urine, line).
Gallstone pancreatitis
- ERCP within 24 hours if there is cholangitis. Not routinely otherwise.
- Gallbladder removal (cholecystectomy) during the same admission for mild gallstone pancreatitis, to prevent another attack.
Other care
- Clot prevention with enoxaparin unless contraindicated.
- Sugar control.
- Alcohol: thiamine, withdrawal assessment and advice.
- Check triglycerides and calcium. Very high triglycerides need specific treatment.
Complications
| When | Complication |
|---|---|
| Early (first week) | Shock, ARDS, kidney injury, low calcium, high sugar, DIC |
| Later | Infected necrosis, fluid collections and pseudocysts, splenic vein thrombosis, bleeding from a pseudoaneurysm |
| Long term | Recurrent attacks, chronic pancreatitis, diabetes |
Common mistakes
- Pouring in 6 litres in the first day.
- Starting antibiotics for every severe case "to prevent infection".
- Keeping the patient nil by mouth for a week.
- Ordering a CT on day 1 to "check severity".
- Measuring lipase every day.
- Missing cholangitis in a jaundiced, feverish patient.
Frequently asked questions
How much fluid is given in acute pancreatitis?
Moderate amounts: a 10 mL/kg bolus of Ringer's lactate if the patient is dry, then about 1.5 mL/kg/hour, adjusted to pulse, BP and urine output. Aggressive fluids cause overload without benefit.
Are antibiotics needed in acute pancreatitis?
Not routinely. They are given for cholangitis, infected necrosis or another proven infection.
When can a patient with pancreatitis eat?
As soon as they are hungry and the pain and vomiting allow, usually within 24–72 hours. Early feeding is better than prolonged fasting.
What is the Glasgow-Imrie score?
A severity score (PANCREAS) scored within 48 hours: PaO₂, age, white count, calcium, urea, LDH or AST, albumin and sugar. A score of 3 or more means severe pancreatitis.
Test yourself
Exam-style questions on this guide, from our two question banks. Choose an answer to see why each option is right or wrong.
1. A patient has severe acute pancreatitis with no fever or jaundice. Should meropenem be started to prevent infection?
Answer: No. Routine prophylactic antibiotics are not recommended. Treat proven infection such as cholangitis or infected necrosis.
- Yes, for all severe cases: Prophylactic antibiotics don't improve outcomes.
- Yes, for 2 weeks: No.
- Only metronidazole: Not indicated.
- Yes, if amylase is above 1000: Amylase doesn't guide antibiotics.
2. On day 2 of mild pancreatitis the patient is hungry and the pain is settling. What diet is recommended?
Answer: Start a low-fat oral diet. Early oral feeding in mild pancreatitis is safe and shortens hospital stay.
- Clear fluids for 5 days: Unnecessary restriction.
- Nil by mouth until amylase is normal: Early feeding is better.
- NG feeding only: Not needed if eating.
- TPN: Not needed.
3. Gallstone pancreatitis is complicated by fever, jaundice and rising bilirubin. What is the next step?
Answer: Antibiotics and ERCP within 24 hours. Cholangitis complicating gallstone pancreatitis needs biliary drainage by ERCP within 24 hours.
- Cholecystectomy today: ERCP first for cholangitis.
- Steroids: Not indicated.
- Ultrasound repeat in a week: Delay is harmful.
- Observation: Cholangitis needs drainage.
4. A 45-year-old with gallstone pancreatitis has, 48 hours after admission, persistent hypotension and rising creatinine despite fluids. What defines this as severe acute pancreatitis?
Answer: Organ failure > 48 hours. Revised Atlanta classification: mild — no organ failure or complications; moderately severe — transient organ failure (< 48 h) or local complications; severe — persistent organ failure > 48 h. Diagnosis needs 2 of 3: typical pain, lipase/amylase > 3× normal, imaging. Management: goal-directed fluids (Ringer’s lactate), analgesia, early enteral feeding, ERCP within 24–72 h for cholangitis, cholecystectomy in the same admission for mild gallstone pancreatitis. Antibiotics only for infected necrosis.
- Amylase > 3× upper limit: Amylase level is diagnostic, not a severity marker.
- Pain radiating to the back: Back pain is a typical feature, not a marker of severity.
- Gallstones on ultrasound: Gallstones are the cause, not a severity measure.
5. Six weeks after acute pancreatitis, a man has early satiety and a 7 cm well-defined fluid collection behind the stomach on CT. What is the preferred treatment if symptomatic?
Answer: Endoscopic cystgastrostomy. A pseudocyst is a fluid collection with a fibrous wall (no epithelium) persisting > 4 weeks after pancreatitis. Many resolve; intervene if symptomatic (pain, gastric outlet obstruction), infected or enlarging. Endoscopic (EUS-guided) cystgastrostomy is preferred once the wall has matured. Complications: infection, haemorrhage (pseudoaneurysm), rupture.
- Immediate open surgery in week 1: The wall is not mature in week 1.
- Percutaneous drain permanently: A permanent drain risks a fistula.
- Antibiotics only: The collection is not infected.
6. A young man has emphysema of the lower lobes and liver cirrhosis. Liver biopsy shows PAS-positive globules in hepatocytes. What is the diagnosis?
Answer: α1-antitrypsin deficiency. α1-antitrypsin deficiency (PiZZ): misfolded protein accumulates in hepatocytes (PAS-positive, diastase-resistant globules) causing cirrhosis, while low serum levels leave lung elastin unprotected from neutrophil elastase, causing panacinar emphysema of the lower lobes, worse in smokers.
- Haemochromatosis: Iron, bronze diabetes.
- Wilson's disease: Copper, Kayser–Fleischer rings.
- Alcoholic liver disease: Mallory bodies; no emphysema link.
- Primary biliary cholangitis: Antimitochondrial antibodies.
7. Which two causes account for most cases of acute pancreatitis?
Answer: Gallstones and alcohol. Gallstones and alcohol cause about 80% of acute pancreatitis. Others (I GET SMASHED): idiopathic, gallstones, ethanol, trauma, steroids, mumps, autoimmune, scorpion sting, hypercalcaemia/hypertriglyceridaemia, ERCP, drugs (azathioprine, valproate, thiazides). Lipase is more specific than amylase. Fat necrosis with calcium soap formation can cause hypocalcaemia.
- Hypercalcaemia and hypertriglyceridaemia: Less common.
- Mumps and trauma: Less common.
- Drugs and scorpion stings: Rare.
- Hereditary and autoimmune: Rare.
References and dose sources
- ACG guideline: management of acute pancreatitis (2024)
- WATERFALL trial: aggressive or moderate fluids in acute pancreatitis (NEJM 2022)
- NICE NG104: Pancreatitis
- BSG — acute pancreatitis guidance
- Ringer's lactate (Hartmann's solution) dosing: Drugs.com: Lactated Ringer's dosage (see also our ringer's lactate (hartmann's solution) dose page)
- Morphine dosing: Drugs.com: Morphine dosage (see also our morphine dose page)
- Ondansetron dosing: Drugs.com: Ondansetron dosage (see also our ondansetron dose page)
- Paracetamol dosing: Drugs.com: Acetaminophen (paracetamol) dosage (see also our paracetamol dose page)
- Enoxaparin dosing: Drugs.com: Enoxaparin dosage (see also our enoxaparin dose page)
International guidance is linked where it reflects good practice. Where your hospital’s protocol differs, follow your hospital.