In which scenario should aspirin be avoided?

Aspirin should be avoided in the scenario of severe liver impairment due to its potential for exacerbating liver complications and increasing the risk of bleeding. The liver is crucial for metabolizing aspirin, and when liver function is significantly compromised, the clearance of the drug can be reduced, leading to elevated blood levels and an increased risk of adverse effects, including gastrointestinal bleeding and hepatotoxicity.

In contrast, using aspirin in post-operative recovery may be acceptable depending on the surgical procedure and the patient's overall health; it is often used for its analgesic properties. Mild allergic rhinitis can also be treated with aspirin if there are no other contraindications, as it may help alleviate symptoms due to its anti-inflammatory effects. While a history of peptic ulcers does raise concerns about gastrointestinal bleeding, aspirin may still be used with caution if the patient is monitored closely and provided with gastroprotective measures, though patients with severe liver impairment would be at higher risk and generally should avoid aspirin altogether.