Ammonia test cost in Napa, CA
In Napa, CA, 1 hospital lists a cash price for ammonia blood test: from $17.85 to $17.85, with a median of $17.85. Across California, the median is $180.96 at 206 hospitals.
Cash prices at 1 facility for code 82140, as an outpatient — the setting a self-pay patient normally buys. Collected Sep 23, 2026; the hospital files themselves were last updated between Apr 1, 2026 and Apr 1, 2026.
Where each hospital's price falls
Each dot is one hospital's cash price on a scale from the lowest to the highest in Napa, CA.
Hospitals, cheapest first
| Hospital | Cash price | List price | Insurers pay | Off list | File date |
|---|---|---|---|---|---|
| Providence Queen of the Valley Medical Center lowest Napa, CA · (707) 252-4411 HC ASSAY OF AMMONIA CDM | $17.85 | $35.00 | — | 49% | Apr 1, 2026 source file |
| Providence Queen of the Valley Medical Center Napa, CA · (707) 252-4411 HC ASSAY OF AMMONIA LAB | $131.07 | $257.00 | — | 49% | Apr 1, 2026 source file |
| Providence Queen of the Valley Medical Center Napa, CA · (707) 252-4411 HC ASSAY OF AMMONIA LAB | $486.03 | $953.00 | — | 49% | Apr 1, 2026 source file |
Outpatient: lowest $17.85, median $17.85, highest $17.85.
As an inpatient, the same code is billed by 1 facility here, median $17.85. Inpatient and outpatient prices are not comparable and are kept on separate pages: the inpatient charge covers admission, not the same purchase.
What it is
An ammonia test measures ammonia in the blood. It is used for confusion or drowsiness in people with liver disease and for some rare inherited disorders in newborns.
What the price covers
The price usually covers running the test. The blood draw (36415) is often billed as a separate line.