LONGITUDINAL-STUDY OF LEVODOPA CARBIDOPA FOR CHILDHOOD AMBLYOPIA

To determine the tolerability and efficacy of levodopa/carbidopa combi ned with occlusion therapy for childhood amblyopia, a double-masked pl acebo-controlled randomized longitudinal study was performed on 10 amb lyopic children between 6 and 14 years of age. Subjects received, on a verage, 20/5 mg levodopa/carbidopa or 20 mg of placebo three times per day combined with part-time occlusion over a 3-week period. Visual fu nction was assessed by Early Treatment Diabetic Retinopathy Study (ETD RS) visual acuity charts and by contrast sensitivity. Tolerability was assessed by questionnaire, SMAC (standard laboratory tests; consists of a chem 20 and complete blood count [CBC]) analysis, and physical ex amination. Compliance with occlusion and capsule consumption were asse ssed by questionnaire and by capsule count, respectively. At the end o f the dosing regimen, the levodopa/carbidopa group significantly impro ved in visual acuity by 2.7 lines and in mean contrast sensitivity by 72% in the amblyopic eye. The placebo group improved in visual acuity by 1.6 lines in the amblyopic eye. Tolerability and occlusion complian ce were similar between groups; however, capsule ingestion compliance was significantly lower in the levodopa/carbidopa group. One month aft er the termination of treatment, the levodopa/carbidopa group maintain ed a significant 1.2-line improvement in visual acuity and 74% improve ment in contrast sensitivity in the amblyopic eye. The placebo group d id not maintain an improvement in visual acuity between the eyes. It i s concluded that levodopa/carbidopa, at an average of 0.48/0.12 mg/kg, is well tolerated and, when combined with part-time occlusion, is eff icacious in improving visual function in amblyopic children.