Fever is a frequent cause of admission to the Emergency Department (ED) around the world. While it can be caused by a wide range of conditions, the most effective treatment based on its etiology is still undetermined. This observational, prospective, single-center study enrolled adult patients who accessed the ED for fever, with the aim to define the most effective treatment for them.

Physicians were free to administer paracetamol 1000 mg (P), the combination paracetamol 500 mg/ibuprofen 150 mg (PI) or Ibuprofen 600 mg (I).The primary endpoint was both 1-degree and 1-point reduction in body temperature for all associated symptoms on the Numeric Rating Scale (NRS) after 1 hour (T1). Secondary endpoint was the reduction of at least 2 points on the NRS after two hours (T2). Adverse events, the needing of a rescue therapy and the response based on the underlying etiology (bacterial, viral, or immune/neoplastic) were also evaluated.

Inclusion Criteria:

• fever with/without associated symptoms
• adults who had given their consent to participate in the study.

Exclusion Criteria:

• age < 18 years old
• contraindications or allergies to Paracetamol, Ibuprofen or to the combination Paracetamol/Ibuprofen
• patients unable to take oral drugs
• patients who did not express their consent to participate to the study

Adults > 18 years old with fever and associated symptoms accessing the ED