What causes the lower eyelid to twitch constantly?

Lower eyelid twitching, medically known as eyelid spasm, is usually caused by involuntary contractions of the eyelid muscles. This condition is typically temporary and may result from fatigue, stress, lack of sleep, or excessive caffeine intake. Occasional eyelid twitching generally does not require significant concern. If the twitching persists or occurs frequently, it may indicate chronic eyelid spasm or a facial nerve disorder, and medical evaluation should be sought. In some cases, dry eyes can also lead to eyelid spasms, and appropriate eye lubrication may help alleviate symptoms. If eyelid twitching continues unabated or is accompanied by other symptoms such as vision loss or facial muscle weakness, prompt medical attention at a hospital is advised.