Timothy Niessen
Experienced in Delirium

Dr. Timothy Niessen

Internal Medicine
Johns Hopkins Medicine
The Johns Hopkins Hospital
1800 Orleans Street, 
Baltimore, MD 
17 Years of Experience

Experienced in Delirium
Johns Hopkins Medicine
The Johns Hopkins Hospital
1800 Orleans Street, 
Baltimore, MD 
OverviewInsuranceLocationsClinical ResearchSimilar Doctors

Overview

Dr. Timothy M. Niessen is an assistant professor of medicine at the Johns Hopkins University School of Medicine. His areas of clinical expertise are internal medicine and medical education. Dr. Niessen earned his M.D. and completed his residency at Johns Hopkins. He holds an M.P.H. from the Johns Hopkins Bloomberg School of Public Health. Lab Website Timothy Niessen Lab The Timothy Niessen Lab studies patient outcomes in the ICU. We are particularly interested in the effects of sleep quality, delirium transitions and sedation on the improvement of intensive care patients. Our investigators also focus on the practices of internal medicine interns, studying the variability of hand washing hygiene, etiquette-based communication and time spent in direct and indirect patient care. We have also studied the onset of myelopathy as a result of B12 deficiency from long-term colchicine treatment and recreational nitrous oxide use.

Dr. Niessen is rated as an Experienced provider by MediFind in the treatment of Delirium. His top area of expertise is Delirium.

His clinical research consists of co-authoring 24 peer reviewed articles. MediFind looks at clinical research from the past 15 years. In particular, he has co-authored 2 articles in the study of Delirium.

Graduate Institution
Johns Hopkins Bloomberg School Of Public Health, MPH, 2009, 2009
Residency
Johns Hopkins University School of Medicine, Medicine, 2012
Specialties
Internal Medicine
Licenses
Internal Medicine in MD
Board Certifications
American Board Of Internal Medicine
Hospital Affiliations
The Johns Hopkins Hospital
Languages Spoken
English
Gender
Male

Insurance

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Locations

The Johns Hopkins Hospital
1800 Orleans Street, Baltimore, MD 21287
Call: 410-955-5000

Clinical Research

Clinical research consists of overseeing clinical studies of patients undergoing new treatments and therapies, and publishing articles in peer reviewed medical journals. Providers who actively participate in clinical research are generally at the forefront of the fields and aware of the most up-to-date advances in treatments for their patients.


24 Total Publications

Performance of pulmonary physical exam skills by internal medicine interns.
Performance of pulmonary physical exam skills by internal medicine interns.
Journal: Diagnosis (Berlin, Germany)
Published: August 24, 2025
View All 24 Publications
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Areas of Expertise

MediFind evaluates expertise by pulling from factors such as number of articles a doctor has published in medical journals, participation in clinical trials, speaking at industry conferences, prescribing and referral patterns, and strength of connections with other experts in their field.

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