What's the difference between aspirin and paracetamol ? which is better for headaches or fever?

Two different meds: Aspirin belongs to the family of non-steroidal antiinflammatory medications that are know to be fever reducers, pain relievers, and inflammation killers. Paracetamol is a stand alone medication in its class and works as a fever reducer and a pain killer. Their mechanism of action is different. Both can work on headache and fever and can be used alternatively. Aspirin is known to irritate GI tract.

Headaches or fever: They both have their advantages/ disadvantages. Either would likely work for headache / fever. Which would be better depends on the patient. The major difference is that Aspirin has an anti inflammatory effect. Paracetamol does not. Paracetamol is easier on the stomach. There are products that combine the two (excedrin back and body & goodys back and body)