| Criterion | Values | Rules to apply | |
| Delay from initial drug component intake to onset of reaction (index day) | Suggestive: +3 | From 5 to 28 days | –3 to 3 |
| Compatible: +2 | From 29 to 56 days | ||
| Likely: +1 | From 1 to 4 days | ||
| Unlikely: –1 | >56 days | ||
| Excluded: –3 | Drug started on or after the index day | ||
| In case of previous reaction to the same drug, only changes for: Suggestive: +3: from 1 to 4 days Likely: +1: from 5 to 56 days | |||
| Drug present in the body on index day | Definite: 0 | Drug continued up to index day or stopped at a time point less than five times the elimination half-life* before the index day | –3 to 0 |
| Doubtful: –1 | Drug stopped at a time point prior to the index day by more than five times the elimination half-life* but liver or kidney function alterations or suspected drug interactions¶ are present | ||
| Excluded: –3 | Drug stopped at a time point prior to the index day by more than five times the elimination half-life*, without liver or kidney function alterations or suspected drug interactions¶ | ||
| Prechallenge/rechallenge | Positive specific for disease and drug: 4 | SJS/TEN after use of same drug | –2 to 4 |
| Positive specific for disease or drug: 2 | SJS/TEN after use of similarΔ drug or other reaction with same drug | ||
| Positive unspecific: 1 | Other reaction after use of similarΔ drug | ||
| Not done/unknown: 0 | No known previous exposure to this drug | ||
| Negative: –2 | Exposure to this drug without any reaction (before or after reaction) | ||
| Dechallenge | Neutral: 0 | Drug stopped (or unknown) | –2 or 0 |
| Negative: –2 | Drug continued without harm | ||
| Type of drug (notoriety) | Strongly associated: 3 | Drug of the "high-risk" list according to previous case-control studies | –1 to 3 |
| Associated: 2 | Drug with definite but lower risk according to previous case-control studies | ||
| Suspected: 1 | Several previous reports, ambiguous epidemiology results (drug "under surveillance") | ||
| Unknown: 0 | All other drugs including newly released ones | ||
| Not suspected: –1 | No evidence of association from previous epidemiology study with sufficient number of exposed controlsΔ | ||
| Intermediate score = total of all previous criteria | |||
| Other cause | Possible: –1 | Rank all drugs from highest to lowest intermediate score | –1 |
| If at least one has an intermediate score >3, subtract 1 point from the score of each of the other drugs taken by the patient (another cause is more likely) | |||
| Final score: –12 to 10 | |||
