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:
| |||
Drug present in the body on index day | Definite: 0 | Drug continued up to index day or stopped at a time point less than 5 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 5 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 5 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 1 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 |
SJS: Stevens-Johnson syndrome; TEN: toxic epidermal necrolysis; ATC: anatomical therapeutic chemical.
* Drug (or active metabolite) elimination half-life from serum and/or tissues (according to pharmacology textbooks), taking into account kidney function for drugs predominantly cleared by kidney and liver function for those with high hepatic clearance.
¶ Suspected interaction was considered when more than 5 drugs were present in a patient's body at the same time.
Δ Similar drug = same ATC code up to the fourth level (chemical subgroups).Do you want to add Medilib to your home screen?