What should not be given to children who have a low-grade fever after vaccination?

Aspirin should not be given to children who have a low-grade fever after vaccination due to the risk of Reye's syndrome, a serious condition that can cause swelling in the liver and brain. Reye's syndrome is particularly associated with the use of aspirin in children and teenagers who are recovering from viral infections, which can include reactions following vaccinations. Given this serious risk, health guidelines strongly advise against using aspirin in children for fever management, making it the appropriate choice in this context.

In contrast, ibuprofen and acetaminophen are commonly recommended to manage pain and fever in children post-vaccination, as they do not carry the same risks as aspirin. Antihistamines, while sometimes used for allergic reactions, are not indicated for the management of fever. This makes aspirin the clear answer to avoid in this scenario.