From the Guidelines
For a 64-year-old woman with recurrent TIAs and gastrointestinal side effects from aspirin, clopidogrel (Plavix) 75 mg daily would be the recommended antiplatelet therapy. This recommendation is based on the guidelines for the management of transient ischemic attacks, which suggest that clopidogrel may be slightly more effective than aspirin in the prevention of further vascular events 1. Additionally, the American Heart Association/American Stroke Association guidelines recommend clopidogrel as an alternative to aspirin for secondary stroke prevention in patients with noncardioembolic ischemic stroke or TIA 1. The antiplatelet drugs guidelines from the American College of Chest Physicians also support the use of clopidogrel for the reduction of atherosclerotic events in patients with recent stroke, recent MI, or established peripheral arterial disease 1.
Some key points to consider when prescribing clopidogrel include:
- Clopidogrel works by irreversibly inhibiting the P2Y12 receptor on platelets, preventing their activation and aggregation, thereby reducing the risk of thromboembolic events.
- If clopidogrel is not tolerated or contraindicated, ticagrelor (Brilinta) 90 mg twice daily could be considered as an alternative, though it may have a higher bleeding risk.
- For patients with very high risk of recurrent events, combination therapy with clopidogrel and low-dose aspirin (using a proton pump inhibitor for gastric protection) might be considered for a short duration (21-90 days), but this increases bleeding risk and should be carefully evaluated.
- The patient should take the medication consistently at the same time each day, and should be advised not to discontinue therapy without consulting her physician as abrupt cessation can increase stroke risk.
It is also important to note that the selection of an antiplatelet agent should be individualized on the basis of patient risk factor profiles, tolerance, and other clinical characteristics 1. In this case, the patient's history of gastrointestinal side effects with aspirin makes clopidogrel a more suitable option.
From the FDA Drug Label
Because the half-life of clopidogrel’s active metabolite is short, it may be possible to restore hemostasis by administering exogenous platelets; however, platelet transfusions within 4 hours of the loading dose or 2 hours of the maintenance dose may be less effective Risk factors for bleeding include concomitant use of other drugs that increase the risk of bleeding (e.g., anticoagulants, antiplatelet agents, and chronic use of NSAIDs) In CAPRIE, gastrointestinal hemorrhage occurred at a rate of 2% in those taking clopidogrel versus 2.7% in those taking aspirin; bleeding requiring hospitalization occurred in 0.7% and 1.1%, respectively.
The best recommendation for the patient at this time is Clopidogrel 75 mg daily. The patient has a history of gastrointestinal side effects with aspirin, and clopidogrel has been shown to have a lower rate of gastrointestinal hemorrhage compared to aspirin in the CAPRIE study 2. Additionally, the patient's recent TIA suggests the need for antiplatelet therapy to reduce the risk of further cardiovascular events.
- Key points:
- Clopidogrel may be a safer alternative to aspirin due to the patient's history of gastrointestinal side effects
- Clopidogrel has been shown to be effective in reducing the risk of cardiovascular events in patients with a history of TIA or stroke
- The patient should be monitored for signs of bleeding, as concomitant use of other drugs that increase the risk of bleeding may increase the risk of adverse events 2
From the Research
Patient's Current Situation
The patient is a 64-year-old woman with a history of two Transient Ischemic Attacks (TIAs) and has recently experienced another TIA. She was previously taking aspirin 325 mg daily but stopped due to severe gastrointestinal side effects.
Recommended Antiplatelet Therapy
Given the patient's history of TIAs and recent event, antiplatelet therapy is crucial for preventing recurrent major vascular events. Considering her gastrointestinal side effects with aspirin, alternative options should be explored.
- Aspirin is widely used for the prevention of recurrent stroke in patients with TIA and ischaemic stroke of arterial origin, because it is effective and inexpensive 3.
- Clopidogrel and the combination of aspirin and extended-release dipyridamole are more effective than aspirin, but are also much more expensive 3.
- A study comparing the efficacy and safety of aspirin plus extended-release dipyridamole versus clopidogrel found that the two regimens had similar rates of recurrent stroke, but the combination of aspirin and extended-release dipyridamole was associated with more major hemorrhagic events 4.
- Combination antiplatelet therapy with clopidogrel and aspirin may reduce the rate of recurrent stroke during the first 3 months after a minor ischemic stroke or TIA, but is associated with a higher risk of major hemorrhage 5, 6.
- Short-duration dual antiplatelet therapy (≤ 1 month) started during the early acute ischemic phase is associated with less bleeding and greater reduction of recurrent strokes compared to monotherapy 6.
Best Recommendation for the Patient
Based on the evidence, the best recommendation for the patient would be to consider alternative antiplatelet therapies that are effective and have a lower risk of gastrointestinal side effects.
- Clopidogrel 75 mg daily could be a suitable option, as it is more effective than aspirin and has a lower risk of gastrointestinal side effects 3, 4.
- The combination of ASA and ER dipyridamole 25/200 mg twice daily could also be considered, but the patient's history of gastrointestinal side effects with aspirin should be taken into account 3, 4.
- Apixaban 5 mg twice daily is not typically used as an antiplatelet agent, but rather as an anticoagulant, and may not be the best option for this patient 3.