Can clopidogrel be stopped in a patient with a history of ischemic heart disease and previous myocardial infarction who has coronary stents and is also taking carvedilol, lisinopril, and carbamazepine?

Can Clopidogrel Be Stopped?

No, clopidogrel should not be stopped in this patient with prior MI and coronary stents, as discontinuation dramatically increases the risk of stent thrombosis, recurrent MI, and death. 1, 2

Critical Context for This Patient

This patient has multiple high-risk features that mandate continued clopidogrel therapy: 1, 3

• History of myocardial infarction - requires at least 12 months of dual antiplatelet therapy (DAPT) from the time of the acute event 1
• Coronary stents in place - the type and timing of stent placement are critical determinants of whether clopidogrel can ever be safely discontinued 1, 4
• Established ischemic heart disease - even after the acute phase, these patients benefit from continued antiplatelet therapy to prevent recurrent events 2

Duration Requirements Based on Stent Type

The minimum duration of clopidogrel therapy depends entirely on what type of stent was placed and when: 1, 4

• Bare-metal stents (BMS): Minimum 1 month of clopidogrel required, ideally continued for 12 months 1, 4
• Drug-eluting stents (DES): Minimum 12 months of clopidogrel absolutely required, particularly in ACS patients 1, 4
• After acute MI (regardless of stent type): Minimum 12 months of DAPT is mandatory 1

The highest risk period for catastrophic stent thrombosis is within the first 30 days after stent placement, with ongoing risk of 0.2-0.6% per year thereafter. 4

When Clopidogrel Can Be Considered for Discontinuation

Clopidogrel may only be considered for discontinuation if ALL of the following criteria are met: 1, 3

• At least 12 months have elapsed since the most recent acute coronary syndrome 1
• At least 12 months have elapsed since stent placement (for DES) or at least 1 month (for BMS) 1, 4
• The patient has no high bleeding risk and has not experienced significant bleeding on DAPT 1
• The patient has no recurrent ischemic symptoms 3
• The patient's cardiologist has been consulted and agrees with discontinuation 3

Specific Contraindications to Stopping Clopidogrel

Clopidogrel must NEVER be stopped in the following scenarios: 1, 3, 2

• Drug-eluting stent placed within the past 12 months 1, 3
• Bare-metal stent placed within the past 1 month 1, 3
• Acute coronary syndrome within the past 12 months 1
• Active or recurrent ischemic symptoms 3

The FDA label explicitly warns that "discontinuation of clopidogrel increases the risk of cardiovascular events" and states that if it must be temporarily discontinued, it should be "restarted as soon as possible." 2

Special Consideration: Carbamazepine Interaction

This patient is taking carbamazepine, which is a strong CYP2C19 inducer. This creates a complex situation: 2

• Carbamazepine may increase the active metabolite levels of clopidogrel, potentially enhancing its antiplatelet effect 2
• The FDA cautions that "as a precaution, avoid concomitant use of strong CYP2C19 inducers" due to increased bleeding risk 2
• However, this is NOT a reason to stop clopidogrel - rather, it requires closer monitoring for bleeding complications 2

If Temporary Discontinuation Is Absolutely Necessary

Only in the setting of active major bleeding or urgent surgery should clopidogrel be temporarily held: 1, 3, 5

• For elective surgery, discontinue clopidogrel 5 days before the procedure to allow adequate dissipation of its irreversible antiplatelet effect 1, 5, 2
• For urgent surgery that cannot be delayed, clopidogrel should be stopped for at least 24 hours if possible 5
• Resume clopidogrel as soon as hemostasis is achieved - delays beyond 24-48 hours dramatically increase stent thrombosis risk 3, 2
• For patients with DES placed within 12 months, the risk of fatal stent thrombosis from stopping clopidogrel may exceed the bleeding risk 3

Ongoing Management

Aspirin should be continued indefinitely in all patients with coronary artery disease, even if clopidogrel is eventually discontinued. 1, 5 The combination of aspirin 81 mg daily plus clopidogrel 75 mg daily represents standard DAPT dosing. 4

All patients on DAPT should receive proton pump inhibitor therapy to reduce gastrointestinal bleeding risk, though omeprazole and esomeprazole should be avoided as they significantly reduce clopidogrel's antiplatelet activity. 3, 2

Bottom Line for This Patient

Without knowing the exact timing and type of this patient's stents, the safest recommendation is to continue clopidogrel indefinitely. 1, 3 Contact the patient's cardiologist before making any changes to antiplatelet therapy, as they will have the critical information about stent type, timing, and the patient's overall cardiovascular risk profile. 3