Conjunctival congestion in patients may be caused by conjunctivitis, keratitis, acute iridocyclitis, ocular trauma, visual fatigue and so on. 1. Conjunctivitis: when the patient’s immunity decreases or when exposed to strong disease-causing factors, it can lead to inflammatory reaction of the conjunctiva, and under the stimulation of inflammation, the patient can have uncomfortable symptoms such as redness, swelling, heat and pain in the eyes. 2. Keratitis: patients with keratitis may also experience symptoms such as bloodshot eyes, accompanied by photophobia, decreased vision, increased eye secretions and other symptoms. 3. Eye trauma: eye trauma patients such as cornea, conjunctival tissue abrasions or cracks, etc., can lead to eye congestion, but also with eye pain, subcutaneous bruising and other symptoms. 4. Visual fatigue: patients who use their eyes for a long time in close proximity, such as looking at a cell phone for a long time, reading and writing for a long time, etc., may experience visual fatigue, and patients may experience symptoms such as soreness, dryness, conjunctival congestion and other discomforts. It is recommended that patients with obvious eye congestion consult a doctor in time to assess their condition and follow the doctor’s instructions for treatment.