Blepharoconjunctivitis is a condition that causes swelling of the outer eyelids and the conjunctiva, the thin mucous layer that acts as a protective layer for the inner eyelids and front of the eyeball. The condition is actually the simultaneous occurrence of two separate eye conditions: blepharitis and conjunctivitis. Blepharitis affects the outer eyelids, while conjunctivitis occurs in the conjunctiva.

Blepharitis is an infection typically caused by the bacteria Staphylococcus aureus. Its most common symptoms are red eyelids, an itching or burning sensation, or severe dry skin flakes on the eyelids. The infection can usually be treated with an over the counter eyelid cleaner, which is formulated to be gentle enough on thin eyelid skin, but potent enough to prevent the harboring of bacteria. If blepharitis is left untreated, the infection can spread to conjunctiva.

When the blepharitis infection reaches the conjunctiva, it causes conjunctivitis to also occur. Conjunctivitis, more commonly referred to as pink eye, can occur by itself and be caused by allergies. In babies, it can be due to unopened tear ducts. Blepharoconjunctivitis happens when the bacteria that caused blepharitis spreads from the outer eyelid to the transparent mucous lining on the inside of the eye. It irritates blood vessels of the eye, making them more noticeable than the white parts and giving a pink look.

In addition to irritated blood vessels, the eyes may also burn or itch. Blepharoconjunctivitis may cause the inner eye to excrete a thin discharge. If the discharge collects overnight and dries, it can make the eyelids dry shut and have to be pried open in the morning.

Blepharoconjunctivitis is contagious, and can occur if a person is exposed to the bacteria through skin-to-skin contact or through using contact lenses or eye makeup products that are contaminated. When a person gets blepharoconjunctivitis, it can spread and infect others for up to 14 days after he or she is initially infected; therefore, a person with the infection is recommended to limit contact with others until the infection is completely treated.

Antibacterial medications usually suffice to treat the bacteria that causes the infection. The medication is typically in the form of eyedrops, but is also available in a topical version. The topical version is applied directly to the eyelids and surface of the eyeballs and is often recommended for babies or small children who have difficulty using eye drops. The medications can cause temporary vision impairment, but it usually subsides within 30 minutes. The symptoms of blepharoconjunctivitis, such as redness and discharge, will generally go away within two days, but the person will still contagious for 14 days.