From the FDA Drug Label
Stop use and ask doctor if ... fever gets worse or lasts more than 3 days Fever should be monitored for 3 days. 1
- Monitor fever for 3 days to assess if it gets worse or lasts longer than expected.
- If fever persists or worsens after 3 days, stop use and ask a doctor.
From the Research
Fever should be monitored until it resolves completely, typically for 3-5 days in most common illnesses. For mild fevers (below 102°F or 38.9°C) in otherwise healthy adults, monitoring can be less frequent, perhaps 2-3 times daily 2. For higher fevers, more frequent monitoring every 4-6 hours is recommended, especially when using fever-reducing medications like acetaminophen (Tylenol) or ibuprofen (Advil, Motrin) to track their effectiveness. In children, closer monitoring is advised, particularly for infants and young children.
Key Considerations
- Seek immediate medical attention if fever exceeds 103°F (39.4°C) in adults or 102.2°F (39°C) in children, persists beyond 3-5 days, or is accompanied by concerning symptoms like severe headache, stiff neck, difficulty breathing, or confusion.
- Fever itself is a protective immune response that helps fight infection by creating an environment less favorable for pathogen replication while activating immune system components, so some degree of fever can be beneficial in fighting illness 3.
- The evaluation of fever should consider both infectious and non-infectious etiologies, and a broad differential diagnosis should be maintained to avoid pitfalls in patient care 2.
- In specific contexts, such as postoperative or postpartum settings, the approach to fever evaluation may need to be tailored to consider common causes in these populations, such as surgical site infections or endometritis 4, 5.