Doctor profile · Federal record

Dr. Mark Johnson, M.D.

Nephrology Physician (CMS: Nephrology) · Internal Medicine Physician · Morristown, NJ

  • NPI 1578670931
  • Accepts Medicare
  • 23 yrs in practice
  • Male
  • Group practice
  • No sanctions

Practice & contact

NPPES Updated May 11, 2026
Primary practice
100 Madison Ave
Morristown, NJ 079606136
(973) 971-7165
fax (973) 290-7521
Mailing address
Po Box 23831
Newark, NJ 071890831

Credentials & registration

NPPES · NUCC
NPI registered
August 2006 — 20 yrs on file
Profile last updated
January 7, 2010
Year of graduation
2003 — 23 yrs since
Specialty taxonomy
207RN0300X — NUCC code
State license (1)
New Jersey #25MA08685600
Medicaid
NY #02784701

Federal sanctions & exclusions

OIG LEIE Updated May 11, 2026

No sanctions, exclusions or revocations on file

Checked against OIG LEIE on NPI 1578670931. Last verified May 11, 2026.

Medicare procedures · 2023

Top services delivered

CMS Provider Utilization
Total services
1,827
Distinct HCPCS
6
Medicare allowed
$219,193
HCPCS Description Services Patients Avg allowed
99233 Subsequent hospital care with moderate levelof medical decision making, if using time, at least 50 minutes 797 293 $128
99232 Subsequent hospital care with moderate levelof medical decision making, if using time, at least 35 minutes 590 309 $85
99223 Initial hospital care with moderate level of medical decision making, if using time, at least 75 minutes 246 232 $186
99213 Established patient office or other outpatient visit, 20-29 minutes 137 75 $98
99204 New patient office or other outpatient visit, 45-59 minutes 36 36 $183
90935 Hemodialysis procedure with physician evaluation 21 17 $76

In context: peer comparison

Among 5 peers in Morristown Nephrology Physician, average services per provider: 185. This provider delivers 9.9× the peer median.

Medicare Part D · 2023

Top prescriptions

CMS Part D Prescriber
Total claims
111
Patients
12
Total drug cost
$1,159
Drug Type Claims Patients Total cost
Losartan Potassium Generic 25 12 $383
Amlodipine Besylate Generic 23 0 $184
Hydrochlorothiazide Generic 21 0 $112
Furosemide Generic 18 0 $75
Calcitriol Generic 13 0 $152
Torsemide Generic 11 0 $253

Frequently asked questions

Auto-generated from federal data
What is Dr. Mark Johnson's medical specialty?
Dr. Mark Johnson practices Nephrology Physician in Morristown, NJ.
Where does Dr. Mark Johnson practice?
Dr. Mark Johnson practices at 100 Madison Ave, Morristown, NJ 079606136. Office phone: 9739717165.
What is Dr. Mark Johnson's NPI?
Dr. Mark Johnson's National Provider Identifier (NPI) is 1578670931, issued by NPPES.
Does Dr. Mark Johnson accept Medicare assignment?
Yes. Dr. Mark Johnson accepts Medicare assignment, meaning Medicare-allowed amounts are accepted as full payment for covered services.
What procedures does Dr. Mark Johnson commonly perform?
Top Medicare-reported procedures in 2023: Subsequent hospital care with moderate levelof medical decision making (HCPCS 99233); Subsequent hospital care with moderate levelof medical decision making (HCPCS 99232); Initial hospital care with moderate level of medical decision making (HCPCS 99223). Source: CMS Medicare Physician & Other Practitioners file.