Complications of an Untreated Sinus Infection

A mild case of acute sinusitis can be treated at home with over-the-counter medications and natural remedies like nasal irrigation, steam inhalation and other treatments. However, cases of chronic sinusitis may require more intense treatment, like surgery. If a chronic sinus infection is left untreated, there are many serious and potentially life-threatening complications that may arise.

Read below about the consequences of an untreated sinus infection, and the best ways to jump start a treatment plan after being diagnosed with a chronic sinus infection.


Failure to treat a chronic sinus infection can lead to several, serious complications.

Complication 1: Further Infection

Infection is a typical complication of any untreated illness, however infected sinuses are particularly dangerous due to their proximity to the eyes and brain. The infection can travel to the bloodstream, to the bones, eyes and even the brain.

A sinus infection can affect the eyes and brain when it spreads along the pathways of blood vessels or the nervous system. Children are at higher risk for sinus infection complications in the eyes and brain since their facial bones are still maturing and opens between the sinuses and the eye sockets/brain have not yet closed.

Sinus infections that spread to the eye socket lead to an increase in swollen tissue around the eyes. As a result, the eyes can look puffy or swollen shut. In some cases, the swollen might occur behind the eyes, pushing the eyes forward in the socket and preventing the eyelids from closing.

The eye socket is a very small, enclosed area, meaning that swelling can cause increased pressure that can lead to permanent eye damage is treatment is not sought immediately. So if you are suffering from an untreated sinus infection, and have severe eye pain or visual loss you should seek medical attention immediately.

Brain Infection

In rare cases, an untreated sinus infection can spread to the brain and cause a variety of terrible illnesses, including  abscesses and meningitis. If the infection spreads to the tissue of the brain, then you are at risk for seizures, brain damage or even death.


The black arrows point to a brain abscess, a severe consequence of untreated chronic sinusitis.

If you suspect you may have chronic sinusitis and at-home treatments have not alleviated your symptoms, consult with your ENT doctor as soon as possible, especially if you show signs of meningitis (headache, fever, nausea and stiff neck).

Complication 2: Ear Infection

An untreated sinus infection can also spread to the ear canal, inner ear or middle ear. Ear infections are typically very painful and if not treated immediately, can lead to permanent auditory impairment or deafness in severe cases.

Complication 3: Immune System Effects

If you allow a sinus infection to remain inside your body, your immune system will fight to rid it from your system. If you do not give your body added weapons to fight the infection – like antibiotics, antihistamines or decongestants – your immune system will gradually weaken over time due to the strain of the infection. Unfortunately, too much medication can also weaken the immune system so a balanced approach to treatment is required.

Complication 4: Anosmia

An untreated chronic sinus infection can alter the normal functions of your nose over time. Specifically, your olfactory glands can suffer damage along with your ability to differentiate between different smells. The sinus infection impairs these nasal functions until the infection is treated, and if too much time passes, the damage could be permanent and you may develop anosmia (a condition whereby a person loses their sense of smell entirely).

Complication 5: Asthma

Sufferers of asthma are also likely to be negatively affected by an untreated sinus infection. Research shows that infections can not only aggravate, but worsen asthma. Because sinus infections affect one’s ability to breathe normally, any pre-existing breathing conditions, like asthma, are therefore also affected.

Complication 6: Resistance to Antibiotics

If a chronic sinus infection is left untreated for a significant amount of time, doctors have found that it may cause a resistance to antibiotics. If an infection is not timely treated, our body will eventually mold itself around the infection, thereby altering your immune system and the normal way your body rids itself of infection. Consequently, when you start to feel the symptoms of a chronic sinus infection, your body may not respond as forcefully to antibiotics as it once did.


Untreated sinus infection complications may include a resistance to helpful antibiotics.


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