Conjunctivitis is inflammation of the conjunctiva, the thin membrane covering the white of the eye and inner eyelids. It can result from infections, allergies or irritants and commonly causes redness, watering and discomfort. Below are practical, non-personal medical details on causes, transmission, prevention and when to get clinical assessment.
Types and common causes
Conjunctivitis commonly presents as viral, bacterial or allergic. Viral cases often occur with upper respiratory infections and may start in one eye then involve the other. Bacterial conjunctivitis can produce thicker discharge. Allergic conjunctivitis is triggered by pollen, dust or animal dander and usually affects both eyes. Chemical exposure, contact lens misuse or systemic conditions can produce similar eye inflammation.
Typical symptoms and red flags
Usual symptoms include eye redness, tearing, a gritty or foreign-body sensation, discharge or crusting, and itching—especially with allergic causes. Seek immediate medical attention if you experience sudden vision loss, severe eye pain, intense light sensitivity, or an eye injury or chemical exposure. For milder or unclear symptoms, primary care or eye specialists can evaluate and advise on contagion risk and next steps.
How it spreads and prevention steps
Viral and bacterial conjunctivitis can spread via direct contact (hands), contaminated towels, bedding or cosmetics. To reduce transmission, practice regular handwashing, avoid touching or rubbing the eyes, do not share personal items, and follow contact lens hygiene recommendations. For allergic conjunctivitis, limiting exposure to known triggers and using environmental control measures helps reduce symptoms.
Diagnosis, referral and follow-up
Diagnosis is usually based on clinical examination. In selected cases, samples from eye discharge may be sent for laboratory testing to identify bacterial causes. Refer to ophthalmology when vision is affected, symptoms are severe, recurrent, in contact lens users, or if there is concern for a more serious ocular condition. Emergency assessment is warranted for chemical burns, trauma, or rapidly worsening vision.