Physician Profile
William C. O'Callahan, MD
Unclaimed ProfileAbout Dr. O'callahan
William C. O'Callahan, MD practices emergency medicine in Holden, MA. William is a 1990 graduate of University of Massachusetts Medical School. According to Medicare claims data, William cared for 958 Medicare patients across 988 services. The services billed most often include established patient office or other outpatient visit with low level od decision making, if using time, 20 minutes or more, established patient office or other outpatient visit with moderate level of decision making, if using time, 30 minutes or more, and x-ray of chest, 2 views.
Summarised automatically from public NPI registry and CMS Medicare data. Not written or reviewed by this provider. Claim this profile to replace it.
Education & Training
Specialty
Credentials & Licensing
License numbers are what the provider reported to NPPES when the NPI was issued or updated. NPPES does not verify licensure; confirm current standing with the state licensing board.
Medicare information
Exactly as CMS reports it (National Downloadable File, Opt-Out Affidavits, Order & Referring). Not an insurance directory; confirm coverage with the office.
Contact Information
- (508) 829-3800
- Email not available
Practice Locations
5 SHREWSBURY ST STE D
Holden, MA 01520
2040 Boston Rd Ste 5
Wilbraham, MA 01095
2040 Boston Road Ste 5
Wilbraham, MA 01095
688 Bliss Road
Longmeadow, MA 01106
Conditions Commonly Evaluated or Treated
Within Emergency Medicine generally. Availability varies by clinician, training and location — this profile has not been claimed, so nothing here is a personal claim by the provider.
Conditions
Abdomen & Digestion
- Appendicitis
- Lower gastrointestinal bleeding
- Vomiting or throwing up blood
Allergy & Immune
- Angioedema
Allergy & Immunology
- Severe Allergic Reaction
Bites & Stings
- Snake Bite or Venomous Sting
- Spider or insect sting reaction
Blood & Circulation
- Deep vein thrombosis
Brain & Nerves
- Delirium
- Fainting and syncope
- Seizure in Child
- Severe headache or sudden migraine
- Status epilepticus
- Stroke
- Transient ischemic attack
Breathing
- Choking or swallowed object
- Coughing up blood
- Severe asthma attack
- Shortness of breath
Digestion & Stomach
- Abdominal Pain
- Acute gallbladder inflammation
- Bowel obstruction
Ear, Nose & Throat
- Nosebleeds
Endocrine & Metabolic
- Dangerous high blood sugar
- Dangerously low blood sugar
Environmental
- Heat stroke
- Hypothermia and frostbite
Eye Care
- Open-globe eye injury
Eye Emergency
- Corneal abrasion
General Emergency
- Severe dehydration
- Uncontrolled bleeding
Heart & Chest
- Acute coronary syndrome
- Heart palpitations
Heart & Circulation
- Dangerous high blood pressure
Heart & Lungs
- Blood Clot in Lung
Infections & Illness
- High fever
- Sepsis or blood infection
Injuries & Trauma
- Animal or dog bite
- Bone fractures
- Deep cut or wound
- Dislocated joint
- Severe burn
- Sprains and muscle strains
- Traumatic brain injury
Lungs & Breathing
- Collapsed lung
Men's Health
- Testicular torsion
Poisoning & Environmental
- Smoke Inhalation
Poisoning & Toxins
- Drug overdose or poisoning
Skin & Infections
- Skin abscess or boil
Spine & Back
- Severe back pain
Urinary & Bladder
- Inability to pee
Urinary & Kidney
- Kidney stones
Women's Health
- Ectopic pregnancy
- Heavy vaginal bleeding
Procedures & services
Abdominal Procedures
- Paracentesis
Airway & Breathing
- Emergency surgical airway
Anesthesia & Sedation
- Moderate dental sedation
Breathing & Airway
- Breathing Treatment
- Emergency intubation
Critical Care
- Blood transfusion
- Central line placement
- Chest tube insertion
- CPR and defibrillation
Diagnostics
- Lumbar puncture
- Rapid blood work
Digestive Care
- Urgent upper endoscopy
Ear, Nose & Throat
- Nasal packing for nosebleed
Eye & ENT
- Eye-pressure measurement
- Foreign Object Removal from Eye
- Superficial foreign-body removal
Eye Care
- Emergency Eye Flushing
Heart & Diagnostics
- Cardioversion for rapid heartbeat
- EKG
Heart Care
- Temporary Pacemaker Placement
Imaging & Diagnostics
- Emergency CT scan
- Emergency MRI scan
- Emergency ultrasound
- Emergency X-ray
Injections & Vaccines
- Rabies shot series
- Tetanus shot
Kidney Care
- Emergency dialysis
Lung & Respiratory
- Chest Needle Decompression
- Draining lung fluid
Medications
- Emergency epinephrine injection
- IV medication for severe nausea
- IV medication for severe pain
Mental Health
- Emergency psychiatric evaluation
Minor Procedures
- Fishhook or embedded splinter removal
- Incision and drainage of an abscess
- Nasal cautery for nosebleeds
- Tick Removal
- Urinary catheter insertion
Minor Trauma
- Stuck ring removal
Orthopedic Procedures
- Joint injection or aspiration
Orthopedics
- Popping a dislocated joint back in place
- Splinting and temporary casting
Poisoning & Toxicology
- Antivenom treatment
Specialized Care
- Sexual assault forensic exam
Stroke & Vascular
- Clot busting medication for stroke
Supportive Care
- IV fluids
Toxicology
- Narcan overdose reversal
- Stomach pumping or activated charcoal
Women's Health
- Emergency pelvic exam
Wound Care
- Burn dressing and care
- Skin glue for cuts
- Stitches and Laceration Repair
- Wound cleaning and debridement
- Wound stapling
Procedures Most Often Billed to Medicare
988 services · 958 patients · 14 distinct codes
| Procedure | Type | Code | Services | Compared with peers |
|---|---|---|---|---|
| X-ray of chest, 2 views | Imaging | 71046 |
121 | More than most peers in Emergency Medicine |
| X-ray of foot, minimum of 3 views | Imaging | 73630 |
14 | Less often than most peers in Emergency Medicine |
| Routine electrocardiogram (ecg) using at least 12 leads with interpretation and report | Treatment | 93000 |
12 | Less often than most peers in Emergency Medicine |
| Established patient office or other outpatient visit with low level od decision making, if using time, 20 minutes or more | Office visit | 99213 |
188 | More often than most peers in Emergency Medicine |
| Established patient office or other outpatient visit with moderate level of decision making, if using time, 30 minutes or more | Office visit | 99214 |
179 | More often than most peers in Emergency Medicine |
| New patient office or other outpatient visit with low level of medical decision making, if using time, 30 minutes or more | Office visit | 99203 |
88 | More often than most peers in Emergency Medicine |
| New patient office or other outpatient visit with moderate level of medical decision making, if using time, 45 minutes or more | Office visit | 99204 |
86 | More often than most peers in Emergency Medicine |
| Detection test by multiplex amplified probe technique for severe acute respiratory syndrome coronavirus 2 (sars-cov-2) (covid-19) and influenza virus types a and b | Lab test | 87636 |
66 | More often than most peers in Emergency Medicine |
| Detection test by nucleic acid for multiple types of respiratory virus, multiple types or subtypes, 3-5 targets | Lab test | 87631 |
62 | Too few peers to compare |
| Amplifed dna or rna probe detection of severe acute respiratory syndrome coronavirus 2 (covid-19) antigen | Lab test | 87635 |
51 | More often than most peers in Emergency Medicine |
Source: CMS Medicare public data. Shows how often procedures were billed — not quality of care or patient satisfaction.
Related providers
Connections drawn from the registry and from what providers have told us. A link here is not a referral or an endorsement.
Other emergency physicians at this location 4
Same specialty, same street address — most likely the same department or group.
Also at this address 4
Providers at the same street address. Each files their own registry entry, so a shared practice often appears under several different names.
More connections — 24 related providers in 3 groups
Trained at University of Massachusetts Medical School 8
Other providers in the same specialty who trained at the same institution.
Class of 1990 at University of Massachusetts Medical School 8
Providers who graduated from the same medical school in the same year.
Also performs X-ray of chest, 2 views 8
Providers in MA who bill this service to Medicare most often.
Common questions
What kind of doctor is Dr. O'Callahan?
Dr. O'Callahan is an emergency physician in Holden, MA. That is the designation recorded for this NPI in the federal registry, where it is listed as “Emergency Medicine”.
NPI registry
What is Dr. O'Callahan's address?
Dr. O'Callahan is listed at 5 Shrewsbury St Ste D, Holden, MA 01520. Addresses come from the NPI registry and can lag a move, so confirm before travelling.
NPI registry
How can I make an appointment with Dr. O'Callahan?
The number on file is (508) 829-3800. Guide.md cannot book appointments or pass on messages — please call the office directly.
NPI registry
What is Dr. O'Callahan's NPI number?
Dr. O'Callahan's National Provider Identifier is 1114964186. It is issued by the Centers for Medicare & Medicaid Services and is unique and permanent — it does not change if they move practice.
NPI registry
Where did Dr. O'Callahan train?
Dr. O'Callahan attended University of Massachusetts Medical School, graduating in 1990. This comes from the CMS National Downloadable File.
CMS public data
How long has Dr. O'Callahan been practicing?
Dr. O'Callahan has 36 years experience. Calculated from a graduation year of 1990, reported in the CMS National Downloadable File.
CMS public data
What procedures does Dr. O'Callahan perform?
According to Medicare billing data, Dr. O'Callahan performs imaging including x-ray of chest, 2 views and x-ray of foot, minimum of 3 views; provides treatments such as routine electrocardiogram using at least 12 leads with interpretation and report, alongside routine visits and testing. This reflects Medicare patients only and is billing volume, not a measure of quality.
Medicare claims
Has Dr. O'Callahan confirmed this information?
Not yet. This profile is built from public federal data and has not been confirmed by Dr. O'Callahan. If this is you, claiming it is free.
Guide.md
Provider data sourced from the NPPES NPI Registry and CMS public datasets. Information is provided for reference and is not medical advice.