Dry Eye Syndrome: This is a common condition that can cause eye pain, especially in individuals who spend a lot of time in front of screens, wear contact lenses, or have a history of dry eye. The pain is usually a dull ache or burning sensation.

Conjunctivitis: Also known as pink eye, this condition can cause eye pain, redness, and discharge. It can be viral, bacterial, or allergic in nature.
Blepharitis: Inflammation of the eyelids can cause eye pain, redness, and swelling. It's often associated with skin conditions like acne or eczema.
Corneal Abrasion: A scratch on the cornea can cause significant eye pain, especially when blinking. It's often due to trauma, contact lens use, or foreign bodies in the eye.
Glaucoma: While not always painful, certain types of glaucoma, like acute angle-closure glaucoma, can cause severe eye pain, redness, and vision loss.

Acute Angle-Closure Glaucoma: A medical emergency that requires immediate treatment to prevent permanent vision loss. Symptoms include severe eye pain, redness, blurred vision, and nausea.
Endophthalmitis: A severe infection within the eye that can cause eye pain, redness, and vision loss. It's often a complication of cataract surgery or eye trauma.
Orbital Cellulitis: An infection of the tissues surrounding the eye that can cause eye pain, swelling, and vision changes. It can lead to serious complications if not treated promptly.
Retinal Detachment: A condition where the retina separates from the back of the eye, causing eye pain, flashes of light, and vision loss. It requires urgent medical attention to prevent permanent vision loss.

Scleritis: Inflammation of the sclera (the white part of the eye) that can cause severe eye pain, redness, and tenderness. It's often associated with autoimmune disorders.
Uveitis: Inflammation of the uvea (the middle layer of the eye) that can cause eye pain, redness, and vision changes. It can be associated with autoimmune disorders or infections.
Optic Neuritis: Inflammation of the optic nerve that can cause eye pain, vision loss, and blind spots. It's often associated with multiple sclerosis or other demyelinating diseases.
Trigeminal Neuralgia: A condition that affects the trigeminal nerve, causing severe eye pain, usually on one side of the face. It's often described as a sharp, stabbing pain.