['gastrointestinal problems', 'autism spectrum disorders']
['oral vancomycin', 'moviprep', 'prilosec']

        Inclusion Criteria:

          1. Children ages 7-17 years

          2. Diagnosis of autism per Autism Diagnostic Interview-Revised (ADI-R)

          3. Moderate or Severe GI problems ( on the GSRS, a single score of 4 (severe) on any
             item, or a score of 3 (moderate) on two items, or a score of 2 (mild) or more on any 4
             items

          4. No changes in medications, supplements, diet, therapies, or education in last 3
             months, and no intention to change them during clinical trial

          5. General good physical health aside from gastrointestinal problems

          6. Cognitive Ability to Provide Informed Assent

        Exclusion Criteria:

          1. Antibiotics in last 6 months

          2. Probiotics in last 3 months

          3. Single-gene disorder (Fragile X, etc.)

          4. Major brain malformation

          5. Tube feeding

          6. Severe gastrointestinal problems that require immediate treatment (life-threatening)

          7. Ulcerative Colitis, Crohn's Disease, diagnosed Celiac Disease, Eosinophilic
             Gastroenteritis, or similar conditions

          8. Severely underweight/malnourished

          9. Recent or scheduled surgeries

         10. Current participation in other clinical trials
      