How Long Does a Sinus Infection Last? Day-by-Day Timeline and When to Worry

Written by Cherlie Joseph, MSN, FNP-BC · Medically reviewed by Naurah Gaspard, DNP, FNP-C, FNP-BC · Updated November 2026

Most sinus infections are viral and start to improve within 7 to 10 days, though a stuffy nose or cough can linger for another week or two. Acute sinusitis, by definition, clears within 4 weeks. Symptoms that last 10 days without any improvement, get worse after getting better, or go past 12 weeks deserve a visit with a provider.

Acute, subacute, chronic and recurrent: what the names mean

Providers describe sinusitis by how long it lasts:

Type	How long	What it usually means
Acute	Up to 4 weeks	Most often follows a cold; usually viral
Subacute	4 to 12 weeks	Slow to clear; worth a check-in
Chronic	12 weeks or longer	Ongoing inflammation, often tied to allergies, nasal polyps or structure
Recurrent acute	4 or more separate episodes a year	Clear in between; look for triggers

A typical day-by-day timeline

Every person is different, but a common viral sinus infection follows this pattern:

• Days 1 to 3: A scratchy throat, sneezing and runny nose, often like the start of a cold. Tiredness and a low-grade fever are possible.
• Days 3 to 6: Congestion peaks. Mucus thickens and may turn yellow or green. Facial pressure, a dull headache and postnasal drip are common, and pressure may worsen when you bend over.
• Days 7 to 10: Most people notice steady improvement. Energy returns, pressure eases and drainage thins.
• Days 10 to 21: A mild stuffy nose, throat clearing or a cough from postnasal drip can hang on, especially at night. This lingering tail is common and does not by itself mean a bacterial infection.

The key signal is direction. Feeling a little better each day, even slowly, is reassuring. The 2025 adult sinusitis guideline from the American Academy of Otolaryngology–Head and Neck Surgery (AAO-HNS) says a bacterial infection is more likely if symptoms last at least 10 days with no improvement, or if they get worse within 10 days after you had started to improve.

How long it lasts with antibiotics

When a provider decides an antibiotic is appropriate for a bacterial sinus infection, the usual first choice for adults is amoxicillin with or without clavulanate, typically for 5 to 7 days. Many people feel noticeably better within 2 to 3 days of starting.

The AAO-HNS guideline advises reassessing if you are not improving, or are getting worse, after 3 to 5 days on an antibiotic. At that point your provider may confirm the diagnosis, check for other causes, or switch medicines. Finish the course as prescribed unless your provider tells you otherwise.

For many healthy adults with mild symptoms, watching and waiting with a clear follow-up plan is also a guideline-supported option. Many bacterial sinus infections still clear on their own.

What can make it drag on

The CDC lists several things that raise the risk of sinus infections, and many of them also slow recovery:

• Allergies. Florida's long pollen seasons and indoor mold keep nasal tissue swollen, so drainage stays blocked.
• Smoking or secondhand smoke, which damages the tiny hairs that sweep mucus out of the sinuses.
• Nasal polyps or a deviated septum, which physically narrow the drainage pathways.
• A weakened immune system or medicines that suppress it.
• Overusing decongestant sprays. Using oxymetazoline longer than the label's 3 days can cause rebound congestion that feels like the infection never ends.

How to feel better sooner

• Rinse with saline once or twice a day. Use distilled, sterile or boiled-then-cooled water, never plain tap water, as the FDA advises.
• Try a nasal steroid spray such as fluticasone or budesonide daily; it can take a few days to help.
• Use pain relievers like acetaminophen or ibuprofen as the label directs for pressure and headache.
• Sleep with your head raised to reduce nighttime drip and cough.
• Drink plenty of fluids and use warm compresses or steam for comfort.

Frequently asked questions

Can a sinus infection go away on its own?

Yes. The CDC notes that most sinus infections get better without antibiotics. Comfort care such as saline rinses, steroid sprays and pain relievers helps while your body clears it.

How long is a sinus infection contagious?

The sinus inflammation itself is not typically contagious, but the cold virus that often starts it can spread, usually most in the first few days of symptoms. Handwashing and covering coughs help protect others.

Why do I still have a cough after my sinus infection?

Mucus dripping down the back of the throat can keep irritating it for a week or two after other symptoms improve. A cough lasting more than 3 weeks, or one with fever, chest pain or shortness of breath, should be checked.

Sources

• CDC: Sinus Infection Basics
• AAO-HNS: Clinical Practice Guideline: Adult Sinusitis Update (2025) summary
• FDA: Is Rinsing Your Sinuses With Neti Pots Safe?

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• Sinus infection vs cold: how to tell the difference
• Do you need antibiotics for a sinus infection?
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• Browse all conditions and treatments A to Z

This article is for general education and is not a substitute for medical advice. Treatment, including any prescription, is decided by a licensed provider after reviewing your health history. OurTopClinic is not for emergencies; if you have a medical emergency, call 911. OurTopClinic serves adults located in Florida, New Mexico, Oregon and Washington. Learn more at ourtopclinic.com.