As a medication, lysine is used probably most commonly in the treatment of herpes simplex labialis, better known simply as herpes or cold sores. It works best as a preventative option, although it can reduce how long an outbreak lasts.
Anisocoria is a condition in which the two pupils of the eye are different sizes; in other words one pupil is larger than the other. In some cases, the abnormal pupil may be the one that is smaller and in other cases the abnormal pupil may be the one that is larger.
Epilepsy and stroke can also cause your pupils to dilate when they would not normally do this. This symptom will usually dissipate after a period of time, but it does signal something serious. Eye doctors can dilate eyes during an exam with eye drops. Doctors will use mydiatric drops during the exam.