RUCAM (Drug- and Herb-Induced Liver Injury Causality)
The updated RUCAM (Roussel Uclaf Causality Assessment Method, Danan and Teschke 2016) grades the probability that a particular drug or herb caused an episode of liver injury.
Open the calculator → Runs in your browser. Data leaves only if you deliberately send a problem report from the interactive tool.
Example
- ALT
- 500 U/L
- The laboratory upper limit of normal for ALT
- 40 U/L
- ALP
- 120 U/L
- The laboratory upper limit of normal for ALP
- 120 U/L
- Time to onset
- first-5-90
- Course after stopping the drug
- fall-50-by-8-days
- Age 55 years or over
- No
- Alcohol use, or pregnancy on the cholestatic scale
- No
- Concomitant drugs
- No concomitant drug, or timing incompatible
- Exclusion of other causes
- All group I and group II causes excluded
The other 2 values
- Previous information on hepatotoxicity
- Reaction is in the product label
- Response to readministration
- Not done, or not interpretable
Result: 9
The tool opens with these values already filled in. Replace them with your own.
What the result means
- R ratio
- PICKS THE SCALE before any item is answered. Hepatocellular at 5 or above, cholestatic at 2 or below, mixed strictly between.
- Mixed
- HAS NO TABLE OF ITS OWN - it is scored on the CHOLESTATIC table.
- Two tables
- They differ in 4 of 7 domains under the SAME names: latency windows, 30 vs 180 day dechallenge, -2..+3 vs 0..+2, risk line.
- Timing
- CAN EXCLUDE THE CASE OUTRIGHT. Onset before starting, or too long after stopping, gives NO total at all.
- 0 or less
- Excluded.
- 1 to 2
- Unlikely.
- 3 to 5
- Possible.
- 6 to 8
- Probable.
- 9 or more
- Highly probable.
- Unequal ranges
- Best reachable is 14 hepatocellular vs 13 cholestatic, yet both share these bands.
- Negatives
- Concomitant drugs and an alternative diagnosis each reach -3. A case can be argued OUT of causality.
- Scope
- CAUSALITY, not severity. Not a diagnosis. NEVER a justification for readministration.
What you enter
- ALT.
- The laboratory upper limit of normal for ALT.
- ALP.
- The laboratory upper limit of normal for ALP.
- Time to onset.
- Course after stopping the drug.
- Age 55 years or over.
- Alcohol use, or pregnancy on the cholestatic scale.
- Concomitant drugs.
- Exclusion of other causes.
The other 2 fields
- ALT. Scores nothing directly; it is half the R ratio that selects the scoring table.
- ALP. Scores nothing directly; it is the other half of the R ratio.
- Time to onset. THE DAY WINDOWS AND POINTS DEPEND ON THE SCALE the R ratio selected. Two values EXCLUDE the case rather than scoring it.
- Course after stopping the drug. THE VALID VALUES DIFFER BY SCALE: the hepatocellular table runs -2 to +3 over 30 days, the cholestatic 0 to +2 over 180 days.
- Alcohol use, or pregnancy on the cholestatic scale. ONE SHARED LINE worth 1 point, and the risk domain is capped at 2.
- Concomitant drugs [none-or-incompatible = No concomitant drug, or timing incompatible (0); compatible-timing = Concomitant drug with compatible or suggestive timing (-1); known-hepatotoxin = Known hepatotoxin with compatible timing (-2); proven-cause = Concomitant drug with evidence for its role (positive rechallenge or validated test) (-3)]. Reaches -3.
- Exclusion of other causes [all-excluded = All group I and group II causes excluded (2); group1-excluded = All 6 group I causes excluded (1); four-or-five-excluded = Only 4 or 5 group I causes excluded (0); fewer-than-four = Fewer than 4 group I causes excluded (-2); alternative-highly-probable = An alternative cause is highly probable (-3)]. Reaches -3.
- Previous information on hepatotoxicity [labeled = Reaction is in the product label (2); published = Published case reports, but not labeled (1); unknown = No published association (0)]
- Response to readministration [positive = Doubling of the relevant test with the drug alone (3); compatible = Doubling with the drug given again alongside the one already in use (1); negative = Given again after recovery with no rise (-2); not-done = Not done, or not interpretable (0)]. SCORED BECAUSE IT SOMETIMES HAPPENS, NOT BECAUSE IT IS ADVISABLE.
How this is calculated
Danan G, Teschke R. RUCAM in drug and herb induced liver injury: the update. Int J Mol Sci. 2016;17(1):14. Scoring tables cross-checked against LiverTox (NIDDK), RUCAM in drug induced liver injury. Read the source ↗
A reference and educational tool. Not medical, legal, or financial advice, and not a substitute for clinician judgment.