The split is timeline, not symptoms: a cold peaks at day 3-5 and improves by day 7-10, while a bacterial sinus infection shows as symptoms past 10 days, "double worsening" (better, then slammed back), or high fever plus thick one-sided discharge for 3-4 days.
Green mucus alone proves nothing; viral colds color mucus too. Either way, the home kit works: saline rinses, humidifier, hydration, acetaminophen or ibuprofen, and decongestant spray for brutal congestion (3-day cap, or rebound hits). The antibiotic reality: most sinus infections, bacterial included, resolve without antibiotics, and guidelines favor watchful waiting for non-severe cases, reserving antibiotics for the severe, worsening, or persistent. Emergency lines: eye swelling or redness, vision changes, severe headache with stiff neck, or confusion, because spread beyond the sinuses is an emergency.
What to do
Common questions
Is it a sinus infection or a cold?
Both start the same way (stuffy nose, thick drainage, face pressure), which is why the distinction is about the timeline, not the symptoms. A cold is viral, peaks around day 3 to 5, and is clearly improving by day 7 to 10. A bacterial sinus infection, the kind that might earn antibiotics, declares itself through three patterns, per MedlinePlus and standard guidance: symptoms lasting past 10 days without improvement; "double worsening," where you were getting better and then slam back with worse congestion, pain, or fever; or a severe start with high fever (102-plus) plus thick, colored, often one-sided discharge for 3 to 4 consecutive days. The tell that surprises people: green or yellow mucus alone means nothing, since viral colds turn mucus colors too; color is not a bacteria detector. What helps either way: saline rinses (the single most useful move), a humidifier, hydration, rest, acetaminophen or ibuprofen for pain and fever, and a short course of a decongestant spray for brutal congestion (3 days maximum, or rebound congestion sets in). The antibiotic question: most sinus infections, even bacterial ones, resolve without antibiotics, and guidelines favor watchful waiting with a backup prescription for cases that are not severe; antibiotics are for the severe, the worsening, or the persistent, per the overuse concerns the CDC tracks. The see-a-doctor lines beyond the patterns above: swelling or redness around the eye, vision changes, severe headache with stiff neck, or confusion, because infection spreading beyond the sinuses is an emergency.