Howard Greller, MD
Howard Greller, MD is a Medical Toxicology (Emergency Medicine) Physician in Newark, NJ, registered under NPI 1376631085. This provider registers 3 separate taxonomy codes, which usually means they practise across more than one recognised specialty.
Getting there
The practice address on file is 150 BERGEN ST DEPT OF, Newark, NJ 07103. We have not yet mapped what surrounds this office — parking, transit, and nearby pharmacies are added as our data collection reaches each location.
Credentials and Medicare
| Licence | State | Specialty |
|---|---|---|
| 25MA11394200 | NJ | Emergency Medicine Physician |
| 61-20314 | NY | Addiction Medicine (Preventive Medicine)… |
| 224207 | NY | Emergency Medicine Physician |
| 25MA11394200 | NJ | Addiction Medicine (Preventive Medicine)… |
| 224207 | NY | Medical Toxicology (Emergency Medicine)… |
| 25MA11394200 | NJ | Medical Toxicology (Emergency Medicine)… primary |
Licences are recorded in 2 states: NJ, NY. Providers licensed in several states often practise near a state border or deliver telehealth across state lines.
- Status
- Approved
- Provider type
- Practitioner - Emergency Medicine
- PAC ID
- 5395739072
- Enrollment ID
- I20220504001420
Medicare enrolment is recorded as approved under the provider type Practitioner - Emergency Medicine. Being enrolled means the provider can bill Medicare; it does not tell you whether they are currently accepting new Medicare patients. Call the office to confirm.
Licensed in 2 states
This provider holds licences in 2 states: New Jersey and New York. The practice address on file is in Newark, NJ, but a licence in another state usually means they see patients there too — either at a second location or by telehealth. If the address above is far from you, it is worth calling to ask whether they practise closer to where you live.
- Licence
- 25MA11394200
- Specialty
- Emergency Medicine Physician
Licence numbers are self-reported to NPPES at registration. They do not confirm a licence is currently active, in good standing, or valid for the specialty shown — only the state board can tell you that, which is why we link to each one.
What Medical Toxicology covers
Medical toxicologists are physicians who specialize in the prevention, evaluation, treatment and monitoring of injury and illness from exposures to drugs and chemicals, as well as biological and radiological agents. Medical toxicologists care for people in clinical, academic, governmental and public health settings, and provide poison control center leadership. Important areas of medical toxicology include acute drug poisoning, adverse drug events, drug abuse, addiction and withdrawal, chemicals and hazardous materials, terrorism preparedness, venomous bites and stings and environmental and workplace exposures. NUCC Health Care Provider Taxonomy, code 207PT0002X
All registered taxonomy codes
This provider registers 6 taxonomy codes. The primary code is what appears on most claims; the others record additional recognised specialties.
| Code | Specialty | Licence | State | |
|---|---|---|---|---|
| 207P00000X | Emergency Medicine Physician | 25MA11394200 | NJ | |
| 2083A0300X | Addiction Medicine (Preventive Medicine) Physician Addiction Medicine | 61-20314 | NY | |
| 207P00000X | Emergency Medicine Physician | 224207 | NY | |
| 2083A0300X | Addiction Medicine (Preventive Medicine) Physician Addiction Medicine | 25MA11394200 | NJ | |
| 207PT0002X | Medical Toxicology (Emergency Medicine) Physician Medical Toxicology | 224207 | NY | |
| 207PT0002X | Medical Toxicology (Emergency Medicine) Physician Medical Toxicology | 25MA11394200 | NJ | primary |
The taxonomy records how the provider classifies their own practice. It does not confirm which conditions they currently treat, whether they are accepting new patients, or which insurance they take — call the office for that.
Full NPPES record
An NPI-1 identifies a single person. It stays with the clinician for life, even if they move practice or change state, which is why the address on file can lag behind where they actually work today.
| NPI | 1376631085 valid check digit |
|---|---|
| Entity type | Individual (NPI-1) |
| Enumeration date | Oct 10, 2006 |
| Last updated | Jul 16, 2026 |
| Status | Active |
| Sole proprietor | No |
| Gender | Male |
| Credential | MD |
| Practice address |
150 BERGEN ST DEPT OF Newark, NJ 07103 (973) 972-9280 |
| Other identifiers |
224207
· Other (NY) |
Number check
How the check works, step by step
Every NPI carries a Luhn check digit — the same scheme used on credit cards. CMS prefixes the number with 80840 before computing it, which marks it as a US health identifier.
| Digit | 8 | 0 | 8 | 4 | 0 | 1 | 3 | 7 | 6 | 6 | 3 | 1 | 0 | 8 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Doubled? | — | ×2 | — | ×2 | — | ×2 | — | ×2 | — | ×2 | — | ×2 | — | ×2 |
| Value | 8 | 0 | 8 | 8 | 0 | 2 | 3 | 5 | 6 | 3 | 3 | 2 | 0 | 7 |
Sum = 55 · next multiple of 10 = 60 · check digit = 5 · actual last digit = 5
A valid check digit only means the number is well-formed. It does not mean the provider is licensed, active, or in good standing — those are separate questions answered by the sections above.