Elevated Creatine Kinase due to Potential Drug Interaction With Ticagrelor and Atorvastatin

Purpose: Ticagrelor and atorvastatin are commonly used medications in the management of acute coronary syndrome and percutaneous intervention. This is a report of a patient case of a potential drug interaction leading to the use of alternative therapy. Case Report: A 58-year-old male presented for cardiac catheterization following an abnormal stress test. He underwent placement of a drug-eluting stent and was started on ticagrelor. Three months later, he was noted to have elevated creatine kinase (CK), thought to be related to a potential drug–drug interaction between ticagrelor and atorvastatin. Ticagrelor was discontinued and he was successfully transitioned to clopidogrel. CK returned to normal within weeks of this change. Discussion: Pharmacokinetic studies have demonstrated a potential interaction between ticagrelor and atorvastatin but have not been deemed clinically significant. To date, only one other case report has been published discussing this interaction and consideration of alternative therapy. This case report is unique, with ticagrelor being the only new medication added prior to the abnormal CK finding. Conclusions: A probable drug–drug interaction occurred with concomitant ticagrelor and atorvastatin. While this interaction may not always be clinically significant, it is reasonable to consider in patients who present with signs and symptoms of adverse effects.