|Developing an eye twitch out of the blue can be perplexing, not to mention very annoying. In most cases, however, eye twitching is a harmless condition that goes a way with time. Small twitches or fasciculations of the upper or lower eyelid need to be distinguished from eye tics, as they only involve a few muscle fiber bundles as apposed to tics which involve whole muscles.
These fasciculations may feel very noticeable, but in most cases they can barely be seen. More serious eye twitching is usually classified as eye tics and in some cases these can become so severe that it affects visual functioning and may disrupt other aspects of daily life.
The severity and duration of eye twitches often depends on the underlying cause.