Which drug should NOT be given to a patient with chemotherapeutic thrombocytopenia?

In the context of chemotherapeutic thrombocytopenia, the primary concern is the risk of bleeding due to a reduced platelet count. Aspirin (ASA) is an antiplatelet agent that inhibits platelet aggregation, meaning it can interfere with the body's ability to form clots. This makes it particularly dangerous for patients with thrombocytopenia, as their already compromised platelet counts can lead to an increased risk of bleeding complications.

While other options, like acetaminophen, are generally considered safer in terms of their effects on platelet function, ibuprofen and naproxen are also nonsteroidal anti-inflammatory drugs (NSAIDs). They can also pose a risk of GI bleeding and may affect platelet function to some extent, but they do not have the same strong antiplatelet properties as aspirin.

For patients with low platelet counts due to chemotherapy, it is crucial to avoid any medications that can exacerbate bleeding risk. Thus, aspirin is correctly identified as the drug that should not be given in this scenario.