Sinus infections, also known as sinusitis, are a common condition that affect millions of people each year. If you’ve ever experienced facial pressure, nasal congestion, and a persistent headache, you may have wondered whether sinus infections appear suddenly or develop gradually. Understanding the onset of a sinus infection can help you determine whether you need medical attention and how to manage your symptoms effectively. For same-day sinus infection treatment, visit the walk-in clinic at ...