Last week upper left eyelid started twitching 1 or 2 times a day. getting more frequent. not more stressed or sleep deprived or drinking more caffeine than usual. what else could it be?

Myokymia: Most often eyelid twitching is due to muscular irritabiity termed myokymia which is annoying but quite benign. I may be associated with eye strain, fatigue, or stressors, but may occur without any clearcut etiology. It the twitching involves the facial muscles in addition, best to have this evaluated.

Nothing serious: Just a benign muscle twitch. Try drinking more water, and add a magnesium supplement daily. 500mg a day should do the trick in a week or so.

See Eye MD: If it does not resolve in 4-6 weeks then see the eye doctor or PCP to make sure not a neurological problem. It can be treated with BOTOX if the lid spams shut or other parts of the face involved. Most of the time, rest and less stress and seems to resolve on its own.