What causes eye twitching?

Stress, fatigue etc: Commonest cause of eye twitching is stress, followed by fatigue, sleep deprivation, stimulant use (even simply coffee). Other conditions causing eye twitching (much less often) include certain movement disorders (e.g. Tourette's, blepharospasm), focal epilepsy.

Myokymia(if no tic): Random twitching of an eyelid or another small facial muscle, which happens in normal people, is called myokymia (an involuntary, spontaneous, quivering of a few muscle cell bundles within a muscle). Myokymia starts and stops spontaneously. It can last a few minutes to a few days. One should see a doctor if such symptoms persist, keep recurring, or are combined with any other symptoms.

Allergies..: Itching of the eyes is a sign of allergies in general. Other things can get in the eyes and cause them to itch. The eyes are well protected by mast cell that are like little packages of histamine that explode when they come in contact with allergens or broken open by rubbing.

Common problem: Eyelid twitching (myokymia) is a common and largely unexplained problem. It usually goes away on its own but sometimes this takes 3-4 weeks. Occasionally, taking some calcium with magnesium supplements seems to help shorten the episode. Be sure to be getting plenty of rest and avoid extensive eye straining such as long hours in front of computer. If the problem does not resolve see your eye doc.