Ammonia Levels in Humans

Ammonia Levels in Humans

An imbalance in the ammonia levels in humans can be a sign of many health issues including liver and kidney diseases. A blood test can help you determine these levels and take necessary treatment from your doctor. This article gives you a brief information on all this, and more.
Ammonia plays an important role in the biological system of the human body. It is the main source of nitrogen supply which helps in the synthesis of amino acids.
Amino acids are considered to be the building blocks of protein in the body. The proteins are broken down by the intestinal bacteria and form ammonia, which in turn is converted into urea by the liver, and finally excreted by the body in the form of urine through kidneys.
The normal ammonia levels in blood usually ranges from 15-60 mcg/dL (micrograms per deciliter), or 21-50 mcmol/L (micromoles per liter). However, the test results vary from laboratory to laboratory. Therefore, it is best to consult with your doctor regarding the same.
Mentioned below are the normal levels of ammonia in humans categorized by their age.
Classification Normal Range
Newborns 170-340 mcg/dL or 100-200 mcmol/L
Children 70-135 mcg/dL or 41-80 mcmol/L
Adults 15-60 mcg/dL or 21-50 mcmol/L


Liver dysfunction may cause elevated ammonia levels which can be an indication of many health issues. The condition may also be caused due to kidney diseases and dysfunction, due to which filtering of blood in kidneys is affected, leading to elevated levels of ammonia in blood. The amount of ammonia can be detected through a blood test. Your doctor would advice you for the same if he/she finds symptoms of low or high levels of ammonia in your body. These symptoms usually include confusion, hand tremors, symptoms of liver disease, lethargy, excessive sleepiness, and even coma.
Test Procedure to Determine Ammonia Levels in Humans
Before Taking the Test ...
  • Do not eat or drink anything 8 hours before the test is conducted.
  • Refrain yourself from consumption of alcohol and nicotine, as these elements may alter the test results.
  • Make sure that you don't perform any strenuous exercise before the blood test.
  • Inform your doctor about the medicines to consume, if any. There are some medications that can alter the ammonia levels.


Getting the blood test done early in the morning would allow the fasting period to be covered during your sleep. Mentioned below are the steps to perform the blood test to determine ammonia levels in human body.
  • The health professional collects the blood sample from the vein on the back of your hand, or at the inner elbow.
  • A medicated cotton ball is used to clean the site from where the blood will be withdrawn. This is done in order to prevent infection on the punctured site after the blood sample is collected.
  • A plastic band is wrapped around the upper arm so that the flow of the blood is increased towards the veins, which makes it easier for the medical professional to withdraw blood. It also makes the veins pop out, and they become more visible.
  • The healthcare provider then inserts a medicated needle attached with a vial, into the vein and withdraws the desired amount of blood required for the test.
  • Then the plastic band is removed from the upper arm, and once the pressure is off, the needle is withdrawn.
  • A medicated cotton ball is placed on the punctured site, and the site is pressed for sometime to prevent further bleeding and infection.
  • The blood sample is then sent to the laboratory to reveal the results. Ammonia levels in the body help determine the causes behind the disturbing symptoms due to which the test is taken. Usually, the results are available within 12 hours after the test is taken.
Possible Test Results

Low ammonia levels can be a result of high blood pressure or consumption of certain medications. If the test results are higher than the normal range, then this may indicate some underlying health conditions and issues. These conditions may include the following.
  • Cirrhosis of the liver
  • Kidney failure
  • Hepatitis
  • Heart failure
  • Liver diseases
  • Intestinal bleeding
  • Reye Syndrome
  • Internal bleeding in the stomach
Get in touch with your healthcare specialist for further doubts and accurate diagnosis, as the results may vary from laboratory to laboratory.
Disclaimer: This Buzzle article is for informative purposes only, and should not be used as a replacement for expert medical advice.