John Keiser, MD, PHD
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- NPI Number
- 1720194103
- Provider Type
- Individual Practitioner
- Credential
- MD, PHD
- Primary Specialty
- Pathology - Medical Microbiology
- License Number
- MD15828
- Practice Address
- 900 23rd ST NW
- City, State ZIP
- Washington, DC 20037
- Phone
- (202) 994-3391
- Last Updated
- June 8, 2026
- Source
- Publicly available data
John Keiser, MD, PHD is a pathology - medical microbiology provider located in Washington, DC. They offer pathology - medical microbiology services to patients in the Washington area.
As a pathology - medical microbiology provider in Washington, this clinician evaluates and treats patients for a range of common conditions seen in Washington and throughout DC.
The practice is located at 900 23rd ST NW, Washington, DC 20037. Patients can call 2029943391 to schedule an appointment or use the directions link above to find the office from anywhere in the area.
Patients typically visit this provider for common reasons to schedule a visit include annual checkups, new or worsening symptoms, medication refills, lab work, preventive screenings, chronic condition management, and second opinions.
If you plan to see this provider, it is a good idea to confirm that the practice accepts your insurance and is in-network before scheduling. Coverage details vary by plan, and our quote tool can help you compare options in DC.
This profile was last verified on June 8, 2026. Provider information is sourced from publicly available data and may not reflect recent changes. Please confirm details directly with the practice before scheduling.
Call for hours and appointments. Hours may vary by provider and location.
A patient’s guide to pathology - medical microbiology care in Washington, DC.
What a Pathology - Medical Microbiology provider does
Healthcare providers diagnose, treat, and help prevent illness and injury. They work with patients to manage ongoing conditions, interpret test results, prescribe medications when appropriate, and coordinate care with other specialists. Most providers accept both insured and self-pay patients, and many offer telehealth visits for routine concerns.
Common conditions treated
Common conditions evaluated include high blood pressure, diabetes, respiratory infections, allergies, skin conditions, digestive complaints, headaches, and musculoskeletal pain. Providers also handle preventive screenings and routine lab work.
Common reasons to schedule a visit
Common reasons to schedule a visit include annual checkups, new or worsening symptoms, medication refills, lab work, preventive screenings, chronic condition management, and second opinions.
What to expect during a visit
During a typical visit, the provider will review your medical history, ask about current concerns, perform a relevant examination, and recommend next steps such as lifestyle changes, prescriptions, additional testing, or specialist referrals. Bring a list of current medications, recent test results, and questions you would like answered.
Insurance coverage considerations
Most major insurance plans cover preventive care and medically necessary visits, but copays, deductibles, and network restrictions vary. Contact your insurance carrier or use our quote tool to confirm a provider is in-network before scheduling.
How to choose the right pathology - medical microbiology provider in Washington
When choosing a healthcare provider, look for board certification, convenient location and hours, accepted insurance plans, and a communication style that fits your preferences. Patient reviews and hospital affiliations can also help you make a confident decision.
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Insurance acceptance not listed
The public NPI registry does not include insurance acceptance data. Contact the office directly to ask if they accept your insurance plan. You can also use our quote tool to find health plans in DC.
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Common questions about John Keiser, MD, PHD in Washington, DC.
How do I make an appointment with John Keiser, MD, PHD?
Call John Keiser, MD, PHD directly at their Washington office to schedule a visit. You can also use the contact form on this page to send a message and the practice will respond.
Does John Keiser, MD, PHD accept insurance?
Provider insurance information is not included in the public NPI registry data that powers this directory. Contact the office directly to ask whether they accept your specific insurance plan. You can also use our quote tool to find health plans in DC.
What are the office hours for John Keiser, MD, PHD in Washington?
Office hours for John Keiser, MD, PHD in Washington are not currently published. Call the practice directly to confirm hours before your visit.
Is parking available at John Keiser, MD, PHD's Washington location?
Most provider offices in Washington offer on-site or nearby street parking. Call John Keiser, MD, PHD in Washington ahead of time to confirm parking options and accessibility accommodations.
Does John Keiser, MD, PHD accept walk-in appointments?
Walk-in availability for pathology - medical microbiology providers varies by location and day. Call ahead to confirm same-day availability before visiting.
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Claim ProfileData is sourced from publicly available records. Public records do not confirm active license status, quality of care, insurance acceptance, or network participation. Please verify details directly with the provider before scheduling. Last updated June 8, 2026.