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Understanding Your Medical Test: What It Is and What to Expect During the Procedure

Published: August 9, 2026Updated: August 16, 2026

This test measures how well your kidneys clear amylase (a digestive enzyme) from your blood by comparing levels in your blood and urine over 24 hours.

Quick summary

{"Measures amylase enzyme levels in both blood and 24-hour urine sample","Helps diagnose pancreatic diseases like pancreatitis","Assesses kidney function in handling amylase","Requires 24-hour urine collection and a blood draw","Results help differentiate between pancreatic and non-pancreatic causes of elevated amylase"}

Medically reviewed by WellAlly Editorial TeamLast reviewed August 16, 2026Editorial policy

Key facts at a glance

LOINC
1801-0
Short code
Amylase Cl 24h Ur+SerPl-vRate
Synonyms
Amylase Cl 24h Ur+SerPl-vRate
Category
chemistry
Sample
serum
Container
Red-top tube (SST)
Units
N/A
Critical range
— – 500 N/A
Fasting
false
Population
adult
Sex
all
Age range
18–65 years
Specimen volume
5 mL
Stability
Room temperature: 4h, Refrigerated: 24h, Frozen: 7d
Hemolysis max
500
Lipemia max
1000
Icterus max
500
TAT
4–24 hours
Order
routine

This test gives your healthcare provider important information about your health, helping to diagnose a possible condition, monitor an existing problem, or check how well a current treatment is working. Your provider may order it as part of a routine checkup or to investigate specific symptoms you have been experiencing.

The amylase renal clearance test measures the amount of amylase (a digestive enzyme produced by the pancreas and salivary glands) in both your blood and urine. Amylase helps break down carbohydrates in your food. This test evaluates how efficiently your kidneys remove amylase from your blood by comparing the enzyme levels in your serum/plasma and the urine collected over 24 hours. The clearance rate helps doctors understand how well your pancreas and kidneys are functioning.

The test is performed by a trained member of your care team, and the exact steps depend on the type of sample or measurement needed; most tests take only a few minutes, cause little to no discomfort, and you can usually return to your normal activities right afterward.

You will need to collect all urine produced over a 24-hour period in a special container provided by the lab. On the day of the test, a blood sample will also be taken. During the collection period, keep the urine container refrigerated or in a cool place. It is important to collect all urine during the 24 hours and to bring the container to the lab as instructed. Your healthcare provider may ask you to fast (not eat) for a certain period before the blood draw.

Clinical interpretation

How abnormal results are interpreted and what conditions they suggest.

This test is primarily used to evaluate pancreatic function and distinguish between different causes of elevated amylase levels. In acute pancreatitis, both blood and urine amylase levels are typically elevated, along with a high clearance rate. The test helps differentiate pancreatic diseases (like pancreatitis or pancreatic cancer) from non-pancreatic conditions that may cause high amylase, such as kidney disease, salivary gland disorders, or certain medications. A decreased renal clearance may indicate kidney problems, while an increased clearance often points to pancreatic issues. This test is also useful in monitoring chronic pancreatitis and evaluating pancreatic exocrine function.

Frequently asked questions

Why do I need both blood and urine tests?
Comparing amylase levels in both blood and urine helps calculate the clearance rate, which provides more accurate information about pancreatic function than either test alone. It helps doctors determine whether high amylase is due to a pancreatic problem or another condition.
How should I collect the 24-hour urine?
Start by urinating into the toilet at the beginning of the collection period (usually in the morning). For the next 24 hours, collect all urine in the provided container. Keep it refrigerated. At the end of 24 hours, urinate one last time and add that to the container. Return it to the lab as instructed.
Do I need to fast before the test?
Your healthcare provider may ask you to fast for 8-12 hours before the blood draw. Follow their specific instructions. Also, avoid alcohol for 24 hours before the test.
What do abnormal results mean?
High amylase with high clearance typically indicates pancreatic problems like acute or chronic pancreatitis. High amylase with normal or low clearance may suggest kidney disease or other non-pancreatic conditions. Low amylase levels are less common but may indicate pancreatic insufficiency or severe liver disease. Your doctor will interpret your results based on your symptoms and other test findings.
Are there any risks to this test?
The blood draw may cause minor bruising or soreness at the needle site. The 24-hour urine collection has no risks. Very rare complications include fainting or infection at the blood draw site.
  1. 1
    MedlinePlus - AmylaseSource
  2. 2
    May Clinic - PancreatitisSource

Click any link to access the full source. PubMed Central (PMC) links provide free full-text access.

This information is for educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment.

Medical Disclaimer

This content is for general informational and educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment. Always seek the guidance of a qualified healthcare provider with any questions you have about a medical condition, and never disregard professional medical advice or delay seeking it because of something you read here.

If you think you may have a medical emergency, call your local emergency number or go to the nearest emergency department immediately.

Medically reviewed by WellAlly Editorial Team Last reviewed August 16, 2026. · Read our editorial policy