A sinus infection, or sinusitis, is characterized by inflammation of the air-filled cavities within the skull, often triggered by a viral or bacterial infection or by allergies. This condition can cause eye discharge due to the close anatomical relationship between the nasal passages and the tear drainage system. When these passages become inflamed, the resulting pressure and mucus buildup can affect nearby structures. Eye discharge refers to the fluid, mucus, or pus that comes from the eye, and its presence alongside sinus symptoms is a clear sign of this connection.
The Link Between Sinuses and Eye Drainage
The underlying mechanism for eye drainage during sinusitis involves a shared pathway known as the nasolacrimal duct, or tear duct. This channel carries tears from the surface of the eye directly into the nasal cavity, underneath a bony structure called the inferior turbinate. This direct connection means that inflammation in the sinuses can easily affect the duct’s function.
When a sinus infection causes the lining of the nasal cavity and sinuses to swell, this swelling can physically narrow or completely obstruct the opening of the nasolacrimal duct. The duct’s opening is naturally small, about 1–2 millimeters, and swelling of just a few millimeters in the surrounding tissue can effectively seal it shut. This blockage prevents normal tear drainage, causing tears and mucus to back up onto the eye’s surface, a condition medically termed epiphora.
The thick mucus produced during a bacterial sinus infection can act like a plug, capping the narrow duct opening. This obstruction and the general inflammatory environment can also allow the infection itself to travel up the duct, leading to secondary eye issues. Therefore, the eye discharge is often not directly from the sinus cavity but originates from the tear ducts or the eye surface reacting to the blockage and irritation.
Differentiating Discharge Symptoms
The consistency and color of the eye discharge can offer clues about the underlying cause, whether it is simply due to duct blockage or a secondary infection. Watery, clear discharge, often presenting as excessive tearing or a constantly wet eye, is typically associated with the simple congestion and pressure from the sinus infection. This type of discharge results from the tears being unable to drain through the blocked nasolacrimal duct, causing them to spill over the eyelid.
A thicker discharge that is yellow or green, often accompanied by crusting on the eyelids, suggests a bacterial infection. This could be bacterial conjunctivitis, commonly known as pink eye, which may develop as bacteria spread from the sinus through the blocked duct to the eye surface. Alternatively, the thick discharge may signal an infection of the tear sac itself, known as dacryocystitis, which often occurs when the duct is chronically obstructed.
Discharge that is accompanied by tenderness or swelling near the inner corner of the eye, specifically between the eye and the nose, is a strong indicator of dacryocystitis. Recognizing these distinctions is helpful, but any persistent or worsening thick discharge warrants a medical evaluation to determine the need for antibiotics.
Warning Signs Requiring Immediate Care
While many cases of eye discharge resolve as the sinusitis improves, certain symptoms indicate a serious complication. The most significant concern is the potential spread of the infection into the eye socket, a condition called orbital cellulitis. This is a severe infection of the tissues surrounding the eye, which can quickly compromise vision.
Specific warning signs include severe eye pain, especially pain when trying to move the eye, or a noticeable bulging of the eye, medically termed proptosis. Other concerning symptoms are double vision, sudden changes in visual clarity, or an inability to move the eye fully.
The presence of a high fever alongside pronounced swelling and redness around the eye, extending past the eyelid, should prompt an immediate visit to an emergency room. These severe signs indicate the infection has progressed beyond the sinuses and tear duct, necessitating urgent and often intravenous antibiotic treatment.