A client previously experienced a severe anaphylactic reaction to penicillin G. Which medication class should not be administered to this client due to the potential for cross-sensitivity?

A. Reye syndrome is correct because administering aspirin to children, especially during viral illnesses like the flu, can lead to this serious and potentially fatal condition characterized by acute encephalopathy and liver failure.

B. Excess antiplatelet action is incorrect; while aspirin does have antiplatelet effects, this is not the primary concern in a child with a viral illness.

C. Asthma is incorrect; while some individuals with asthma may have sensitivity to aspirin, it is not specifically related to the child's flulike illness.

D. Salicylate poisoning is incorrect; while high doses of aspirin can lead to toxicity, the immediate risk in the context of flu-like illness is Reye syndrome, which is a more specific concern.

A. An INR of 5.0 indicates a significantly increased risk of bleeding, and administering vitamin K is the appropriate antidote for reversing the effects of warfarin. This is a critical intervention to restore coagulation.

B. Increasing the dose of warfarin is inappropriate in this scenario because the INR is already elevated; it would further increase bleeding risk.

C. While heparin can be used for anticoagulation, it is not appropriate to administer it while the INR is dangerously high without reversing the warfarin first.

D. Continuing warfarin is unsafe at this INR level due to the high risk of bleeding; monitoring for symptoms without intervention is not adequate care.