A CareKinesis Clinical Pharmacist performed a CMR on a newly enrolled 75 year old PACE participant. She had a significant PMHx of atrial fibrillation, CAD, Hyperlipidemia, CKD, pain, and allergies. Her current medications were:
Amiodarone 200mg daily
Amlodipine 5mg daily
Simvastatin 40mg daily
Clopidogrel 75mg daily
Acetaminophen 650mg QHS
INTERVENTION & RECOMMENDATION:
While the participant was stable on her current regimen upon enrollment, the CareKinesis Clinical Pharmacist saw an opportunity to mitigate medication risk. The use of amiodarone with higher doses of simvastatin may be associated with an increased risk of myopathy. Furthermore, co-administration of simvastatin with amlodipine may significantly increase the plasma concentrations of simvastatin and its active metabolite. The interactions may potentiate the risk of statin-induced myopathy due to competitive inhibition of CYP450 3A4. Based on the FDA recommendations, simvastatin daily dosage should not exceed 20 mg when used in combination with amlodipine.
Considering these interactions, the CK Clinical Pharmacist identified other statins, such as fluvastatin and pravastatin, that would be safer alternatives in this participant, as they are not metabolized as extensively by CYP450 3A4.
The CK Clinical Pharmacist explained the above rationale and recommended that the physician consider switching the participant to pravastatin 10mg daily (initial low dose due to renal impairment) and titrate up as clinically indicated based on lipid panel to minimize the risk of interactions.
The physician made the recommended medication change and decreased the risk of potential adverse effects, including myopathy and rhabdomyolysis.