Uncontrolled eye tremors, or nystagmus, may be caused by certain medications, head injuries, stroke, vitamin B12 deficiencies, inner ear disorders or diseases affecting the brain such as multiple sclerosis. According to MedlinePlus, nystagmus present at birth is called infantile nystagmus syndrome, a generally mild condition not related to other disorders.
MedlinePlus states that the rapid eye tremors of nystagmus may be vertical, horizontal or rotary, and they may occur in one or both of the eyes. Some of the most common medications that may trigger eye tremors include the anti-seizure medication phenytoin and other sedating medications. Individuals may also experience nystagmus if they consume excessive alcohol.
Nystagmus may occur in sufferers of multiple sclerosis due to the formation of plaques along the nerve pathways that control eye movement, according to the National Multiple Sclerosis Society. Those experiencing any type of tremor may also experience difficulty swallowing and difficulty speaking. Tremors resulting from MS are difficult to treat, but certain medications have shown some success.
Eye tremors are not the same as eye twitching, which generally refers to unintentional spasms of the eyelid rather than the eye itself. According to Mayo Clinic, eye twitching may be caused by alcohol intake, stress, smoking, lack of sleep, eye irritation and caffeine intake.