Normal Urine Output Per Hour : Evaluate Your Health Status

How often do you consider the amount and frequency of your urine output? Not very often, right? But did you know your urine can actually give you a great deal of information about your overall health?

Urine output can provide valuable information about your body’s health status, as it can indicate whether there is an underlying medical condition that needs attention.

Basically, normal urine output per hour for adults is approximately  0.5 to 1.5 ml/kg/hour. This range can vary depending on various factors, including fluid intake, overall health status, and medications. 

Let’s dig in!

What Is A Normal Urine Output Per Hour?

Urine output is the amount of urine your body releases quickly. It is measured in milliliters per hour (ml/h) and can indicate how well your kidneys function. However, dehydration can impact urine output even if your kidneys are fine.

Generally, the average urine output per hour is around 0.5 to 1.5 milliliters per kilogram of body weight. For infants, the normal urine output is typically higher at around 1-3 milliliters per hour, while adults older than 65 may have a lower urine output of around 30-80 milliliters per hour.

Though most people urinate every 6 hours, which is considered normal.

Normal Urine Output Per Hour By Ages

The normal urine output per hour can vary depending on age, gender, body size, physical activity, and fluid intake. However, here’s a general overview of the expected urine output per hour by age:

Age GroupNormal Urine Output per Hour
Infants (0-12 months)2 ml/kg/hour  
Toddlers (1-3 years)1.5 ml/kg/hour.
Children (4-13 years)0.5-1.5 ml/kg/hour
Adolescents (14-18 years)1 ml/kg/hour
Adults (19-50 years)0.5 to 1.5 ml/kg/hour
 Older adults (50+ years) 0.5-1 ml/kg/hour  

6 Factors Affecting Urine Output

As we know, the normal range for 24-hour urine volume is 800 to 2,000 milliliters per day (with a normal fluid intake of about 2 liters per day). Urine output, also known as urine volume, can be influenced by several factors, including:

  1. Fluid intake: The amount of fluids you consume can significantly impact your urine output. Drinking fluids, especially water, can increase urine production, while limiting fluid intake can decrease urine output.
  2. Hormonal balance: Certain hormones, such as antidiuretics (ADH) and aldosterone, regulate urine production. Imbalances in these hormones can affect urine output.
  3. Kidney function: Typically, the kidneys are crucial in filtering waste products from the blood and producing urine. Any kidney damage or dysfunction can lead to changes in urine output.
  4. Medical conditions: Several medical conditions, such as diabetes, kidney disease, and heart failure, can affect urine production by altering the body’s fluid balance.
  5. Physical activity: It can affect urine output by increasing the body’s fluid needs and promoting sweating, leading to fluid loss.
  6. Age: As we age, our kidneys may become less efficient at filtering waste and producing urine, which can lead to changes in urine output.

How to Measure Urine Output

If you’re worried that your urine output is too low or too high, here are some tips on how to measure it:

  1. Collect a container to measure urine: Use a clean, dry, and sterile container to collect urine. It should be large enough to hold the expected amount of urine output.
  2. Record the start time: Note the time that the measurement starts so that you can determine the rate of urine output.
  3. Empty the bladder: You will be asked to urinate into the container. Sometimes, a catheter may be used to collect your urine output.
  4. Measure the urine: Use a measuring device, such as a graduated cylinder, to measure the amount of urine in milliliters (ml).
  5. Record the amount of urine: Write down the volume of urine collected and the time the measurement was taken.
  6. Calculate the urine output rate: Divide the volume collected by the hours elapsed since the measurement started. For example, if 200 ml of urine is collected over 4 hours, the urine output rate would be 50 ml per hour.
normal  urine

Causes For An Abnormal Urine Output

Usually, a healthy person should produce urine at a rate of 0.5 to 1.5 cc per kilogram of body weight per hour.

For example, if someone weighs 75 kilograms, their average urine output should be 35 to 105 cc per hour. A person should also be urinating at least every 6 hours.

If a person’s urine output is significantly reduced, it is called oliguria. This means the person produces less than 300 ccs of urine per square meter of their body’s surface area over 24 hours.

For children, the threshold is even lower, with less than 0.5 ccs per kilogram of body weight per hour being considered oliguria.

In adults, oliguria is usually defined as less than 500 cc of urine per day.

Anuria is the absence or minimal production of urine. It produces less than 100 mL of urine daily in adults.

Various factors, including kidney failure, dehydration, and certain medications, can cause this condition.

Take Note: 1 cc= 1 ml

Low urine output (oliguria) can be caused by:

1. Dehydration – when you’re not drinking enough fluids, the kidneys don’t receive enough fluid to work with, resulting in decreased urine output.

2. Kidney disease – when the nephrons (the tiny kidney filtering units) stop working, the glomerular filtration rate decreases, decreasing urine output. In some severe cases, this may lead to kidney failure.

3. Cardiovascular problems – if you experience blood flow problems or congestive heart failure, your kidneys may receive a lower blood volume, resulting in reduced urine output and reduced tissue perfusion of the organs.

4. Urinary tract obstruction – an anatomical defect or kidney stones may obstruct the urine flow, causing a blockage. This can lead to the inability to urinate, which can be a medical emergency.

High urine output (polyuria) can be caused by:

1. Alcohol, caffeine, and diuretics – natural diuretics like alcohol and caffeine can increase urine output.

2. Diabetes mellitus – poorly controlled diabetes can cause excess glucose in the blood. When the urine has too much glucose, it pulls more water from the blood, increasing urine output.

What is a normal urine output per hour?

When to Contact a Medical Professional

Here are some signs that it’s time to contact a medical professional regarding a decrease in urine output:

– If you notice you are producing less urine than usual.

– When your urine looks much darker than usual.

– When you are vomiting, have diarrhea, or have a high fever and can’t get enough fluids by mouth.

– If you experience dizziness, lightheadedness, or a fast pulse with decreased urine output.

Final Verdicts

Now, you understand the factors, reasons, and normal urine per hour by age. So check out your urine production per hour. And if you are concerned about your urine production, it is important to consult a doctor who can identify the underlying cause and recommend appropriate management. Understanding normal urine output can help you take an active role in maintaining your health and well-being.

John Harvey
John Harvey

John Harvey M.D., M.P.H. is the Director of Promo Global Health Institute and a Professor at Promo Chan School of Public Health . As an Internal Medicine physician at Boston Healthcare System, I aim to improve healthcare quality and costs through policy-focused research. I earned my M.D. and M.P.H. from Harvard, and completed fellowships at University of California, San Francisco.

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