Cross-Over Comparison of Gabapentin and Memantine as Treatment for Acquired Nystagmus
Involuntary oscillations of the eyes (nystagmus) impairs vision so that affected patients, who have neurological disorders such as Multiple Sclerosis (MS) , cannot read or watch TV. Two medicines have been reported to suppress nystagmus and improve vision in such patients: gabapentin and memantine. The investigators set out to test which of these two drug was more effective by carrying out a double-blind cross-over study. In this way, we could determine which drug worked best in each patient.
|Study Design:||Allocation: Randomized
Intervention Model: Crossover Assignment
Masking: Double Blind (Subject, Investigator, Outcomes Assessor)
Primary Purpose: Treatment
|Official Title:||Investigation and Treatment of Ocular Motor Disorders: Cross-Over Comparison of Gabapentin and Memantine as Treatment for Nystagmus|
- Visual acuity of each eye, measured during far or near viewing [ Time Frame: After 2 weeks of therapy, for both drugs ] [ Designated as safety issue: No ]
- Median eye speed during attempted visual fixation, of each eye. [ Time Frame: Measured after two weeks of therapy with either drug ] [ Designated as safety issue: No ]
- Patient's report of whether they think that they have benefitted from either drug treatment [ Time Frame: After two weeks of therapy, for either drug ] [ Designated as safety issue: No ]
|Study Start Date:||February 2005|
|Study Completion Date:||May 2009|
|Primary Completion Date:||May 2009 (Final data collection date for primary outcome measure)|
Active Comparator: Gabapentin
Increasing dose to 300 mg four times per day (total of 1200 mg/day)
increasing to 1200 mg/day
Other Name: Neurontin
Active Comparator: Memantine
Increasing dose over two weeks to 20 mg twice/day (total of 40 mg/day).
increasing to 40 mg/day
Other Name: Nameda
The study entails careful measurements of visual acuity and precise measurements of eye movements, using a contact lens device (magnetic search coil method). In this way, it is possible to make objective and reliable measurements of the effect of each drug, which are unbiased by the investigator or the patient.