When a cold or the flu strikes, the discomfort often extends beyond congestion and body aches to the eyes, causing soreness, a deep ache, or sensitivity. This specific pain is not always caused by a direct eye infection, but rather the body’s generalized response to the invading virus or bacteria. The eyes, despite seeming separate, are intimately linked to the respiratory and immune systems through shared pathways and inflammatory responses. This common experience of eye pain during sickness is a signal from the body that the immune system is actively engaged in fighting the infection.
How Systemic Illness Affects Eye Comfort
The deep, aching pain felt behind the eyes during a systemic illness like the flu or a bad cold is often a form of myalgia, or muscle pain. When the body fights an infection, the immune system releases inflammatory proteins known as cytokines into the bloodstream. These cytokines can lead to widespread aches, including the small extraocular muscles that control eye movement, making it painful to move the eyes.
Sinus congestion is another major contributor to eye discomfort because the sinuses are air-filled cavities located close to the eye sockets. When these passages become inflamed and blocked with mucus due to infection, the resulting pressure can cause a dull, heavy feeling or sharp pain around and behind the eyes. This feeling of fullness or pressure often worsens when bending over or straining.
Fever and dehydration, common companions to acute illness, can directly affect the moisture of the ocular surface. A fever increases the body’s overall fluid loss, and when combined with reduced fluid intake, it can lead to dehydration. Dehydration decreases the overall volume of tears, causing the eyes to become dry, irritated, and scratchy, a condition known as dry eye.
Common Localized Eye Infections
Sometimes, the pain is not an indirect result of systemic illness but a direct infection of the eye structure, which frequently occurs alongside a cold or flu. Viral conjunctivitis, commonly known as pink eye, is often caused by the same viruses that cause the common cold, such as adenovirus. This localized infection inflames the thin, clear membrane covering the white of the eye and the inner eyelid, leading to redness, discharge, and a gritty discomfort.
Another type of eye pain is photophobia, or extreme sensitivity to light, which can accompany more severe infections or conditions. Photophobia is a symptom where bright lights cause pain or discomfort. It often occurs with inflammation of the eye’s internal structures, like uveitis, or with severe systemic illnesses like meningitis. Even inflammation on the eye’s surface can increase the reactivity of the corneal nerves to light, causing this painful sensitivity.
Localized bacterial infections, such as a stye or hordeolum, can also cause acute, focused eye pain, often presenting as a tender, red bump on the eyelid. A stye forms when an oil gland at the edge of the eyelid becomes blocked and infected. The localized swelling and pus buildup cause intense, concentrated pain and tenderness in the eyelid itself.
Relief Strategies and When to Seek Medical Care
Managing the discomfort associated with illness-related eye pain often involves simple, actionable strategies that address the underlying causes. Staying properly hydrated by drinking plenty of fluids is important to support tear production and thin mucus secretions, which helps alleviate dryness and sinus pressure. Over-the-counter lubricating eye drops, also known as artificial tears, can soothe irritation by providing temporary moisture to the ocular surface.
Applying a compress can also provide relief, but the type depends on the cause. A warm, damp cloth is best for easing sinus pressure and helping to resolve a stye, while a cool compress may reduce swelling and inflammation from general irritation or conjunctivitis. Nonsteroidal anti-inflammatory drugs (NSAIDs), such as ibuprofen, can help reduce the generalized inflammation and body aches that contribute to the deep-set eye pain. Resting the eyes by limiting screen time is also beneficial.
Identifying certain “red flag” symptoms is important, as some eye pain can signal a more serious condition requiring immediate medical attention. Seek urgent care if you experience sudden, severe eye pain, especially if it is accompanied by rapid vision changes, such as blurred vision, double vision, or seeing halos around lights.
Other warning signs include pain that worsens rapidly, an inability to move the eye, swelling that extends to the cheek, or a high fever with a stiff neck. If eye pain is the result of an infection and does not improve after a few days of self-care, professional evaluation is necessary.