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.
The medical term for dilated pupils is mydriasis. Medications or other drugs can also cause the pupil to dilate, either intentionally or as a side effect. For example, eye care professionals often use eye drops that dilate the pupils in order to examine structures at the back of eye, such as the retina. Other medications and illicit drugs that can dilate the pupils include cough and cold medications, decongestants, cocaine, and marijuana.