Cilostazol Combined with Clopidogrel in CAD: Safety Profile
Adding cilostazol to clopidogrel (Plavix) in patients with coronary artery disease is not harmful and may provide additional cardiovascular benefit without increasing major bleeding risk. 1
Evidence from Guidelines and Clinical Trials
Safety Data from PCI Studies
The American College of Chest Physicians guidelines specifically addressed this combination in patients undergoing coronary stenting who were already taking aspirin and clopidogrel 1:
A systematic review of 10 randomized controlled trials (2,809 patients) comparing triple therapy (aspirin + clopidogrel + cilostazol) to dual therapy (aspirin + clopidogrel) found no significant increase in major bleeding (risk ratio 0.89; 95% CI, 0.46-1.73) 1
In patients with symptomatic peripheral artery disease taking cilostazol, there were no differences in rates of myocardial infarction (1.0% vs 0.8%), stroke (0.5% vs 0.5%), or death (0.6% vs 0.5%) compared to placebo 1
Current Guideline Recommendations
The 2012 ACCP guidelines for patients undergoing PCI with stent placement recommend 2:
- Use low-dose aspirin 75-100 mg daily and clopidogrel 75 mg daily alone rather than adding cilostazol (Grade 1B recommendation)
- Cilostazol 100 mg twice daily may be used as a substitute for either aspirin or clopidogrel in patients with allergy or intolerance to either drug (Grade 2C) 2
Important Contraindication
Cilostazol carries an FDA black-box warning and is absolutely contraindicated in patients with heart failure of any severity 3, 4, 3, 5:
- Other phosphodiesterase inhibitors (milrinone, vesnarinone) have been associated with increased mortality in heart failure patients 3
- The mechanism involves increased intracellular cyclic AMP, which can trigger ventricular tachycardia 4
Clinical Efficacy Evidence
Cardiovascular Outcomes
Multiple meta-analyses demonstrate potential benefits of triple therapy 6, 7:
- Triple antiplatelet therapy reduced major adverse cardiovascular events by 32% (OR 0.68; 95% CI 0.60-0.78) compared to dual therapy 7
- Target lesion revascularization was reduced by 43% (OR 0.57; 95% CI 0.44-0.73) 7
- Stent thrombosis was reduced by 37% (OR 0.63; 95% CI 0.40-0.98) 7
Platelet Reactivity
Cilostazol significantly improves platelet inhibition when added to clopidogrel 7:
- Mean platelet reactivity units decreased by 47.73 units with triple therapy (p<0.0001) 7
- Triple therapy reduced high on-treatment platelet reactivity by 60% (relative risk 0.40; 95% CI 0.30-0.53) 7
Bleeding Risk Profile
The combination does not significantly increase bleeding risk 1, 6, 7:
- No significant difference in major bleeding between triple and dual therapy (OR 1.42; 95% CI 0.52-3.85) 1
- Overall bleeding rates were similar (OR 1.16; 95% CI 0.79-1.69) 6
- This favorable bleeding profile distinguishes cilostazol from adding other antiplatelet agents 7
Common Side Effects and Tolerability
The main limitation is drug discontinuation due to adverse effects 7, 8:
- Headache occurs in up to 25% of patients within the first 2 weeks 4
- Other common side effects include diarrhea, palpitations, dizziness, and tachycardia 3, 4, 3, 4
- Drug discontinuation rates are approximately 60% higher with triple therapy (incident rate ratio 1.59; 95% CI 1.32-1.91) 7
Clinical Decision Framework
For patients with CAD on clopidogrel, cilostazol can be safely added if 1, 3, 4, 3:
- No heart failure is present (absolute contraindication)
- Patient can tolerate common side effects (headache, GI symptoms)
- High-risk features warrant additional antiplatelet therapy (e.g., diabetes, prior PCI, high platelet reactivity) 9, 10
The combination is NOT recommended as routine therapy but may be considered in select high-risk patients who cannot tolerate newer P2Y12 inhibitors (prasugrel, ticagrelor) 2, 11, 12.