Biocompatible intraocular implants include an anti-excitotoxic agent and a biodegradable polymer that is effective to facilitate release of the anti-excitotoxic agent into an eye for an extended period of time. The therapeutic agents of the implants may be associated with a biodegradable polymer matrix, such as a matrix that is substantially free of a polyvinyl alcohol. The implants may be placed in an eye to treat or reduce the occurrence of one or more ocular conditions, such as retinal damage, including glaucoma and proliferative vitreoretinopathy.