Atropine is a medication that comes as an eye drop. This medication has many uses for diagnosing and treating eye conditions. The main effect of atropine is to dilate the eyes and limit the ability to focus at near.
Atropine is routinely used to treat conditions including amblyopia, myopia, and anterior uveitis. Atropine can also be used to help dilate the eyes to be examined in an eye exam. There are rare side effects from using atropine properly, but it can be toxic if ingested orally. An eye doctor will prescribe and manage atropine treatment.
Atropine impacts receptors on the iris and the ciliary body that are connected to the autonomic nervous system.
The medication binds to these receptors to prevent the activation of these receptors and their responses.
In the eye, the receptors are responsible for constricting the pupil in bright light and adjusting the focus when looking at something close.
When atropine is instilled in the eye, both the iris and the ciliary body are prevented from the action.
When atropine is used, the pupil will become large and fixed — unable to constrict.
Vision will also be blurred when looking at a close object or trying to read.
Atropine typically lasts for several days up to a week. The blurry near vision will subside before the pupil shrinks to the size it was before the drop.
Amblyopia is a condition in which one eye does not see as well as the other with no disease or other pathology to explain the difference.
Treatment for amblyopia involves trying to force the weaker or worse-seeing eye to become the primary eye used at times.
This use strengthens the poor vision in the eye and begins to develop a binocular vision system with both eyes contributing to the vision.
One method of forcing the weak eye to be used is to use low-dose atropine in the better-seeing eye.
The atropine causes blurry vision in the typically clear eye, and then the weaker eye will be used.
Myopia, or nearsightedness, can be progressive in children.
It is possible for the amount of myopia to increase dramatically year over year until the end of puberty.
To limit the end amount of myopia, techniques to manage the progression are recommended.
While unable to reverse myopia that is present, it is possible to reduce the risk of advancing amounts — especially in young patients.
One common option for this is using a very low dose of atropine in both eyes.
This amount actually does not create any noticeable effect on pupil size or near vision but acts to mitigate the progression of myopia by preventing peripheral blur.
These drops are used daily and typically are able to limit the progression of myopia by half or more than the normal progression amount.
Anterior uveitis is inflammation of the front of the eye.
This inflammation causes light sensitivity and pain as well as a very red eye.
One option to reduce the pain associated with anterior uveitis is to use atropine or another similar medication to paralyze the ciliary body.
Movement of the ciliary body when the eye focuses will cause intense pain, and atropine can reduce or stop this movement.