An important side effect you need to know is that Sabril can permanently damage the vision of anyone who takes it. People taking Sabril are at risk for vision loss with any amount of Sabril. The risk of vision loss may be higher the more Sabril is taken daily and the longer you take it. This side effect has occurred in 3 of 10 or more of patients taking Sabril. If vision loss occurs, it will not get better.
The most noticeable loss is in your ability to see to the side when you look straight ahead (peripheral vision). People who take Sabril do not lose all of their vision, but some people can have severe loss particularly to their peripheral vision. With severe vision loss you may only be able to see things straight in front of you (sometimes called “tunnel vision”). You may also have blurry vision.
Tell your doctor right away if you or your child:
- Might not be seeing as well as before starting Sabril
- Start to trip, bump into things, or are more clumsy than usual
- Are surprised by people or things coming in front of you that seem to come out of nowhere
Tell your healthcare provider right away if you think that your baby is:
- Not seeing as well as before taking Sabril
- Acting differently than normal
It is recommended that your doctor monitor your (or your child's) vision closely while on Sabril, because there is no way to predict who will experience vision loss or when it may occur. For some people, it develops within a few weeks after starting treatment or sooner. It can also occur any time during treatment, even after months or years, and there is no dose that is free from risk of vision loss. However, taking higher doses or taking Sabril for a longer period of time may increase the risk. There is a possibility that vision loss can worsen despite stopping Sabril as well.
Vision tests cannot prevent the vision damage that can happen with Sabril, but they do allow Sabril to be stopped if vision has gotten worse, which usually will lessen further damage. Even these regular vision tests may not show vision damage before it is serious and permanent. Parents, caregivers, and healthcare providers may not recognize the symptoms, or find vision loss in babies, until it is severe.