Psychiatrist | Geriatric Psychiatry | 47+ years experience

Mary Deirdre Johnston, MD

600 N Wolfe Street, Johns Hopkins University School Of Medicine, Baltimore, Maryland, 21287-7279

About Mary Deirdre Johnston

Mary Deirdre Johnston is a psychiatrist based in Baltimore, Maryland with 47 years of experience in Geriatric Psychiatry. She completed her graduation in 1979. She is also affiliated with hospitals like She accepts the Medicare-approved amount. Patients will not be billed for any more than the Medicare deductible and coinsurance. Active license number of Mary Deirdre Johnston is 9500105 for Geriatric Psychiatry in North Carolina. Her current practice location is 600 N Wolfe Street, Johns Hopkins University School Of Medicine, Baltimore. Patients can contact her at 410-955-5147. Mary Deirdre Johnston, MD, specializes in Geriatric Psychiatry and her NPI number (Unique professional ID assigned by NPPES) is 1881670958.

Mary Deirdre Johnston has psychiatric expertise in prevention, evaluation, diagnosis and treatment of mental and emotional disorders in the elderly, and improvement of psychiatric care for healthy and ill elderly patients.

Practice Information

Mary Deirdre Johnston's specialty, credentials, practice address, contact phone number and fax are as below. Patients can call on the below given phone number for appointment.

Provider Name Mary Deirdre Johnston
Specialization Geriatric Psychiatry
Credentials MD
Accepts Medicare Assignment Yes
Experience 47+ years
Graduation Year 1979
Gender Female
Practice Address: 600 N Wolfe Street, Johns Hopkins University School Of Medicine
Baltimore, MD - 21287-7279

Professional Identification Codes

NPI number stands for National Provider Identifier which is a unique 10-digit identification number issued to healthcare providers in the United States by the Centers for Medicare and Medicaid Services (CMS). NPI details are as mentioned below.

PAC ID 6507872330
Enrollment ID I20060302000323
NPI Number1881670958
NPI Enumeration Date: 20 Dec, 2005
NPI Last Update On: 18 Sep, 2012

Medical Licenses:

Healthcare professionals can hold one or more medical licenses for different specialties in the same state or different states. Related medical licenses for Mary Deirdre Johnston are as mentioned below.

License NumberSpecializationStateStatus
9500105Geriatric Psychiatry North CarolinaPrimary

Hospital Affiliation

Doctors are affiliated to many hospitals whom they worked with in the past or are presently working with. One doctor can be affiliated to four to five hospitals at a time.
Hospital Name (CCN) StateHospital Type
(210009)Baltimore, MDAcute Care Hospital

Group Practice

Group practices are practice of medicine by a group of healthcare professionals who share their premises and other resources. Following list states all the group name with which Mary Deirdre Johnston is associated with along with the number of members in that group.
Organization Name (Group PAC ID) Members
Johns Hopkins University (8921903147)2602

Mailing Address

Business mailing address can be used for mailing purpose only, for visiting purpose patients need to refer above mentioned Practice address.

Mary Deirdre Johnston
9910 Franklin Square Drive Suite 2110, Johns Hopkins University Reimbursement Coordinator
White Marsh, MD - 21236-4902
Phone: 410-933-2718

Book an Appointment with Mary Deirdre Johnston

To schedule an appointment, contact Mary Deirdre Johnston at 600 N Wolfe Street, Johns Hopkins University School Of Medicine, Baltimore, Maryland or call the phone number listed below.

Book an Appointment

Frequently Asked Questions

Below are some commonly asked questions about Mary Deirdre Johnston:

Mary Deirdre Johnston is a psychiatrist specializing in Geriatric Psychiatry. She has psychiatric expertise in prevention, evaluation, diagnosis and treatment of mental and emotional disorders in the elderly, and improvement of psychiatric care for healthy and ill elderly patients.

Mary Deirdre Johnston has approximately 47 years of experience in Geriatric Psychiatry.

Yes, Mary Deirdre Johnston accepts Medicare assignment, meaning the provider participates in Medicare and accepts Medicare-approved amounts for eligible services.

Yes, Mary Deirdre Johnston is currently accepting new patients. To schedule an appointment, contact the office directly and schedule an appointment.
*Availability may change. Please contact the office directly to ask about appointments.

Mary Deirdre Johnston practices at 600 N Wolfe Street, Johns Hopkins University School Of Medicine, Baltimore, Maryland, 21287-7279.

To schedule an appointment with Mary Deirdre Johnston, please contact the office at 410-955-5147.

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**Data of this site is collected from Medicare & Medicaid Services (CMS) and NPPES. Last updated on 14 September, 2026.