Three study visits will include neurological exams, review of medical history, genetic test results and video-taped BFM-DRS motor scales. Patients will receive medication during baseline visit, consisting of either Ampicillin drug or placebo, which will be consumed twice daily for 28 days. Following a washout period (no drugs) of 7 days, patient will return to clinic for second study visit and receive second set of medication (placebo -vs- Ampicillin). Medication will be consumed twice daily for 28 days, with patient returning to clinic after a washout period of 7 days for final study visit in clinic.