Causality Assessment with Naranjo Scale

1. Are there previous conclusive reports on this reaction?

2. Did the adverse event appear after the suspected drug was administered?

3. Did the adverse event improve when the drug was discontinued or a specific antagonist was administered?

4. Did the adverse event reappear when the drug was readministered?

5. Are there alternative causes that could on their own have caused the reaction?

6. Did the reaction reappear when a placebo was given?

7. Was the drug detected in blood or other fluids in concentrations known to be toxic?

8. Was the reaction more severe when the dose was increased or less severe when the dose was decreased?

9. Did the patient have a similar reaction to the same or similar drugs in any previous exposure?

10. Was the adverse event confirmed by any objective evidence?