Ticagrelor-Induced Prolongation of the QTc Interval
Table 1
The Naranjo algorithm to assess the causality. Total score categories are defined as follows: Adverse Drug Reaction (ADR) is: certain >9; probable 5-8; possible 1-4; unlikely 0.
Question
Yes
No
Do not know
Score
Are there previous conclusive reports on this reaction?
+1
0
0
0
Did the adverse event appear after the suspected drug was administered?
+2
-1
0
+2
Did the adverse reaction improve when the drug was discontinued or a specific antagonist was administered?
+1
0
0
+1
Did the adverse reaction reappear when the drug was re-administered?
+2
-1
0
0
Are there alternative causes (other than the drug) that could solely have caused the reaction?
-1
+2
0
+2
Was the drug detected in the blood (or other fluids) in a concentration known to be toxic?
-1
+1
0
0
Was the reaction more severe when the dose was increased, or less severe when the dose was decreased?
+1
0
0
0
Did the patient have a similar reaction to the same or similar drugs in any previous exposure?
+1
0
0
0
Was the adverse event confirmed by objective evidence?
