CILOSTAZOL Drug Interactions: What You Need to Know

INTERACTIONS Strong and moderate CYP3A4 and CYP2C19 inhibitors: Increase exposure to cilostazol. Reduce cilostazol tablets dose ( 2.2 , 7.1 )

7.1 Inhibitors of CYP3A4 or CYP2C19 Inhibitors of CYP3A4 Coadministration of strong (e.g., ketoconazole) and moderate (e.g., erythromycin, diltiazem and grapefruit juice) CYP3A4 inhibitors can increase exposure to cilostazol. Reduce cilostazol dose to 50 mg twice daily when coadministered with strong or moderate inhibitors of CYP3A4 <span class="opacity-50 text-xs">[see Dosage and Administration ( 2.2 ) and Clinical Pharmacology ( 12.3 )]</span>. Inhibitors of CYP2C19 Coadministration with CYP2C19 inhibitors (e.g., omeprazole) increases systemic exposure of cilostazol active metabolites. Reduce cilostazol dose to 50 mg twice daily when coadministered with strong or moderate inhibitors of CYP2C19 <span class="opacity-50 text-xs">[see Dosage and Administration ( 2.2 ) and Clinical Pharmacology ( 12.3 )]</span>.

Cilostazol tablets are contraindicated in patients with: Heart failure of any severity: Cilostazol and several of its metabolites are inhibitors of phosphodiesterase III. Several drugs with this pharmacologic effect have caused decreased survival compared to placebo in patients with class III-IV heart failure. Hypersensitivity to cilostazol or any components of cilostazol tablets (e.g., anaphylaxis, angioedema) Heart failure of any severity ( 4 ) Hypersensitivity to cilostazol or any components of cilostazol tablets ( 4 )

AND PRECAUTIONS Risks of tachycardia, palpitation, tachyarrhythmia or hypotension. Risks of exacerbations of angina pectoris or myocardial infarction in patients with a history of ischemic heart disease ( 5.2 ) Left ventricular outflow tract obstruction has been reported in patients with sigmoid shaped interventricular septum ( 5.1 ) Risks of thrombocytopenia or leukopenia progressing to agranulocytosis-monitor platelets and white blood cell counts ( 5.3 ) Avoid use in patients with hemostatic disorders or active pathologic bleeding ( 5.4 )

5.1 Tachycardia Cilostazol may induce tachycardia, palpitation, tachyarrhythmia or hypotension. The increase in heart rate associated with cilostazol is approximately 5 to 7 bpm. Patients with a history of ischemic heart disease may be at risk for exacerbations of angina pectoris or myocardial infarction.

5.2 Left Ventricular Outflow Tract Obstruction Left ventricular outflow tract obstruction has been reported in patients with sigmoid shaped interventricular septum. Monitor patients for the development of a new systolic murmur or cardiac symptoms after starting cilostazol.

5.3 Hematologic Adverse Reactions Cases of thrombocytopenia or leukopenia progressing to agranulocytosis when cilostazol was not immediately discontinued have been reported. Agranulocytosis is reversible on discontinuation of cilostazol. Monitor platelets and white blood cell counts periodically.

5.4 Hemostatic Disorders or Active Pathologic Bleeding Cilostazol inhibits platelet aggregation in a reversible manner. Cilostazol has not been studied in patients with hemostatic disorders or active pathologic bleeding. Avoid use of cilostazol tablets in these patients.