In adults, pneumonia has clear “red flags” that warrant urgent attention: significant shortness of breath, falling oxygen saturation, worsening chest pain, confusion, low blood pressure, persistent high fever, or rapid clinical deterioration. Older age, comorbidities such as COPD or heart failure, immunosuppression, and pregnancy increase overall risk. If managed at home, lack of meaningful improvement within 48–72 hours—or any worsening—should trigger reassessment. The key operational mistake is “waiting a few more days,” because deterioration can be fast. A safe approach includes early evaluation, a clear monitoring plan, and prompt escalation when red flags appear.