Ammonia Test
Ammonia Test can be requested without a referral, and this overview covers what to expect. An ammonia test measures the amount of ammonia in your blood. Ammonia is a waste product made when your body breaks down protein, and the liver normally converts it into urea for removal. This test is ordered when a clinician suspects the liver is not clearing ammonia properly or wants to monitor a known liver condition.
- Sample type
- blood
- Category
- Liver
- Turnaround
- 1-3 business days
- Price
- $198
- Referral
- Not required
An ammonia test measures the amount of ammonia in your blood. Ammonia is a waste product made when your body breaks down protein, and the liver normally converts it into urea for removal. This test is ordered when a clinician suspects the liver is not clearing ammonia properly or wants to monitor a known liver condition.
What it measures
- Ammonia (NH3) — The main substance measured; high levels can mean the liver is not processing it well.
- Total blood ammonia — The overall amount of ammonia in the sample, reported in micrograms per deciliter (mcg/dL).
- Specimen quality note — Ammonia levels can rise if the sample is handled slowly, so the lab may comment on collection timing.
Who it is for
A clinician may order this test for people with liver disease, unexplained confusion or sleepiness, or symptoms such as vomiting and irritability. It is also used to monitor someone already diagnosed with a liver or metabolic condition.
Preparation
No fasting is usually required, but your clinician may ask you to avoid a high-protein meal or certain medications before the draw. Follow any specific instructions you are given.
Results and what they mean
Results are reported as a number with a reference range, and your clinician interprets them alongside your symptoms, other liver tests, and medical history. A single result rarely tells the whole story. This is general information only and is not medical advice; discuss your results with a qualified clinician.
How to order this test
- Choose the test and place a confidential order online.
- Select a certified collection site and pick a time that suits you.
- Have your specimen collected — most draws take only a few minutes.
- Review results in a secure portal, typically within 1–3 days.
Preparation, hours, and pricing vary by site; confirm details directly with the lab before your visit.
Availability by state
Direct-access online ordering for the ammonia test is available in most states. It is currently unavailable in 6 states:
Everywhere else you can order confidentially and collect your sample at a certified site. Browse by state →
Frequently asked questions
Do I need to fast for an ammonia test?
Fasting is usually not required. Your clinician may give specific timing or diet instructions, so follow those.
What can make ammonia levels go up?
Liver conditions, some medications, and certain metabolic disorders can raise ammonia. Sample handling can also affect the result.
Is a high ammonia level dangerous?
Very high levels can be serious, but only a clinician can judge what your result means for you. Contact your care team with concerns.
How soon will I get results?
Typical turnaround is 1 to 3 business days, though it may vary by lab.