Aspirin adverse effects

Gastrointestinal:
Aspirin use increases the risk of gastrointestinal bleeding. Enteric coating does not seem to reduce this risk. Combining aspirin with other NSAIDs increases the risk.

Central effects:
Large doses of salicylate can cause tinnitus.

Reye's syndrome:
Acute afebrile encephalopathy and fatty liver. Can occur when children or adolescents are given aspirin for a fever or other illnesses or infections. Especially influenza and chicken pox.

Hives:
It is an uncommon reaction to aspirin. Aspirin can induce angioedema in some people.