Most sinus infections are viral and clear up on their own within 7 to 10 days using basic home care and over-the-counter remedies. Antibiotics only help when the infection is bacterial, which accounts for a smaller share of cases. The right treatment depends on how long you’ve been sick, how severe your symptoms are, and whether the cause is viral, bacterial, or tied to chronic inflammation.
How to Tell if You Need Antibiotics
In the first three to four days of a sinus infection, there’s no reliable way to distinguish a viral cause from a bacterial one. The symptoms overlap almost completely: congestion, facial pressure, thick nasal discharge, and sometimes low-grade fever. The timeline of your illness is the most important clue.
A bacterial infection becomes more likely if your symptoms persist without any improvement for at least 10 days, or if you experience what’s called “double sickening,” where you start to feel better around day 5 and then suddenly get worse again. After 10 days of unimproved symptoms, the probability of a bacterial cause rises to roughly 60%. Thick, discolored nasal discharge on its own doesn’t automatically mean bacteria are involved, since viral infections produce it too.
Antibiotics should be considered when symptoms fail to improve within 7 to 10 days or worsen at any point. If your infection is still in the first week and your symptoms are mild to moderate, the standard recommendation is to manage it with supportive care and wait.
Saline Irrigation
Rinsing your nasal passages with salt water is one of the most effective first-line treatments for both acute and chronic sinus infections. It physically flushes out mucus, bacteria, and inflammatory debris, and it helps the tiny hairs inside your sinuses move mucus more efficiently. You can use a squeeze bottle, bulb syringe, or neti pot.
One critical safety point: never use plain tap water. Tap water can contain low levels of bacteria and amoebas that are harmless when swallowed but can cause serious, even fatal, infections when introduced into your nasal passages. The FDA recommends using only distilled water, sterile water, or tap water that has been boiled for 3 to 5 minutes and cooled to lukewarm. Previously boiled water should be used within 24 hours. Filters specifically designed to trap infectious organisms also work.
Steroid Nasal Sprays
Over-the-counter corticosteroid nasal sprays reduce swelling inside the sinus passages, decrease mucus production, and help restore drainage. They work by calming the inflammatory response in the lining of your sinuses and reducing the permeability of blood vessels, which is what causes that swollen, blocked feeling. For people with nasal polyps, steroid sprays have been shown to moderately reduce overall symptom severity and shrink polyp size. They also cut the risk of polyp recurrence after surgery by about 40%.
These sprays take a few days of consistent use to reach full effect. They’re useful for both acute and chronic sinus problems and are often recommended alongside saline irrigation as a starting combination before anything stronger is considered.
Decongestants
Decongestants come in two forms: oral (pills or liquids) and topical (nasal sprays). Both shrink swollen blood vessels in the nasal lining to open up your airways. Topical sprays work faster and more directly, but they carry a risk of rebound congestion if used too long. The traditional guidance is to limit topical decongestant sprays to about three days. Some research suggests that longer use doesn’t always trigger rebound, but since individual responses vary, keeping use brief is the safer approach.
Oral decongestants don’t cause rebound congestion but can raise blood pressure and cause restlessness, so they’re not ideal for everyone.
Pain Relievers
The facial pressure and headache that come with a sinus infection respond well to standard over-the-counter pain relievers. Both ibuprofen and acetaminophen are effective options for easing sinus pressure and pain. Ibuprofen has the added benefit of reducing inflammation, which may provide a slight edge for the swelling component of sinus discomfort.
Antihistamines: Only When Allergies Are Involved
If your sinus infection is triggered or worsened by allergies, antihistamines can help by reducing the allergic swelling that blocks sinus drainage. But for routine sinus infections without an allergy component, antihistamines are not recommended. They can actually thicken mucus and make it harder for your sinuses to drain, potentially prolonging the problem rather than solving it.
Antibiotics for Bacterial Sinus Infections
When a bacterial infection is confirmed or strongly suspected, the standard first choice is amoxicillin or amoxicillin-clavulanate. The specific drug and dose depend on whether you have risk factors for antibiotic-resistant bacteria, such as recent antibiotic use, recent hospitalization, or living in an area with high resistance rates. For uncomplicated cases, a typical course lasts 7 to 10 days.
If your symptoms improve during the first week of antibiotics but then mildly return, a longer course of the same antibiotic is usually the next step rather than switching to a different one. Antibiotics won’t help a viral sinus infection, and taking them unnecessarily contributes to resistance, which is why the 7-to-10-day observation window matters.
When Sinus Infections Become Chronic
Chronic sinusitis means symptoms have lasted 12 weeks or longer despite treatment. At this point, the approach shifts. Treatment typically involves an extended course of antibiotics (2 to 4 weeks for chronic bacterial cases), along with steroid sprays, saline irrigations, oral steroids in some cases, and management of any underlying allergies.
If symptoms persist after this comprehensive medical approach, sinus surgery becomes an option. Functional endoscopic sinus surgery (FESS) opens blocked sinus passages to restore drainage. It’s considered for people whose chronic sinusitis hasn’t responded to optimal medical therapy, those with nasal polyps causing airway obstruction or poorly controlled asthma, and cases involving complications like infection spreading toward the eye socket or skull base. A CT scan is typically done after completing medical treatment to map the sinuses before planning surgery.
Symptoms That Need Immediate Attention
Most sinus infections, even bacterial ones, resolve without complications. But certain symptoms signal that the infection may be spreading beyond the sinuses to nearby structures like the eyes or brain. Seek immediate medical care if you develop pain, swelling, or redness around your eyes, double vision or other vision changes, a high fever, a stiff neck, or confusion. These can indicate orbital or intracranial complications that require urgent treatment.