Dr. Johnston is on Doximity

As a Doximity member you'll join over a million verified healthcare professionals in a private, secure network.

  • Connect with other colleagues in the same hospital or clinic
  • Search all U.S. specialist profiles and refer a patient
  • Read the latest clinical news and earn CME/CEU credits

See Dr. Johnston's full profile

Already have an account?

Education & Training

  • University of Texas Medical Branch Hospitals
    University of Texas Medical Branch HospitalsResidency, Family Medicine, 1988 - 1990
  • Penn State University
    Penn State UniversityInternship, Transitional Year, 1987 - 1988
  • University of Texas Medical Branch
    University of Texas Medical BranchClass of 1987

Certifications & Licensure

  • TX State Medical License
    TX State Medical License 1989 - 2021