Journal of Medical Cases, ISSN 1923-4155 print, 1923-4163 online, Open Access
Article copyright, the authors; Journal compilation copyright, J Med Cases and Elmer Press Inc
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Case Report

Volume 12, Number 1, January 2021, pages 9-12

Alteration of Coagulation Test Results and Vaginal Bleeding Associated With the Use of Feverfew (Tanacetum parthenium)


Table 1. Laboratory Results
TestFirst testAfter 4 monthsNormal range
Prothrombin time (s)27.314.411 - 16
Partial thromboplastin time (s)422918 - 28
Hemoglobin (g/dL)101212 - 15.5


Table 2. The Naranjo Adverse Drug Reaction Probability Scale
The Naranjo adverse drug reaction probability scaleYesNoDo not knowScale
Are there previous conclusive reports on this reaction?+ 1000
Did the adverse event occur after the suspected drug was administered?+ 2- 102
Did the adverse reaction improve when the drug was discontinued, or a specific antagonist was administered?+ 1001
Did the adverse reaction reappear when the drug was readministered?+ 2- 100
Are there alternative causes (other than the drug) that could have on their own caused the reaction?- 1+ 202
Did the reaction reappear when a placebo was given?- 1+ 101
Was the blood detected in the blood (or other fluids) in concentrations known to be toxic?+ 1000
Was the reaction more severe when the dose was increased or less severe when the dose was decreased?+ 1001
Did the patient have a similar reaction to the same or similar drugs in any previous exposure?+ 1000
Was the adverse event confirmed by any objective evidence?+ 1001