Specialty Center Quick Find:

Allergy / Cardiology / Dermatology / Endocrinology / Family Practice / General SurgeryGynecology and Obstetrics / Internal Medicine Hematology and Medical Oncology / Neurology / Neurosurgery / Orthopedics / Pediatrics / Pediatric Cardiology / Pulmonology / Rheumatology / Surgery / Urology

Allergy Specialist

Fred Lewis, M.D. Board Certified in Allergy and Immunology Tests available on site:

  • Drug Allergy Tests
  • Allergy Injections
  • Skin Testing (inhalant & food)
  • Latex and Venom Tests
  • Methocholine Challenge
  • PFTs (Pulmonary Function Test)
  • Oral Food Challenges
  • RAST Testing

Dr. Lewis specializes in diagnosing and treating allergies. An allergy is an acquired abnormal response to a substance (allergen) that causes a reaction within the body. Allergic reactions may include eczema, allergic rhinitis, hay fever, asthma, hives and food allergies. Allergists help patients by determining the causes of allergic reactions and helping to treat symptoms and build patients' tolerance to allergens. Dr. Lewis will see patients of all ages. Make an appointment with our allergy specialist today!

Cardiology Specialist

Matthew Cox, M.D. Board Certified in Cardiology
Tami Buzzard, D.N.P. 
Tests available on site:

  • Echocardiograms
  • Exercise Stress Tests
  • Stress Echocardiograms
  • EKGs • Signal Average EKGs
  • Plethysmography for hemodynamic monitoring
  • Pacemaker / Defibrillator Clinic
  • Lipid Clinic
  • Tilt table
  • Cardiolite and Adenosine Stress Tests
  • 24 Hour Holter Monitoring
  • 30 Day Event Monitoring

Cardiology is the specialty that deals with assessing and treating conditions of the heart. The heart is a hollow, muscular organ which is the "pump" of the circulatory system. Many procedures and diagnostic exams are available within the department to aid in evaluating and diagnosing cardiac problems. We offer a Lipid Clinic to assist you in managing your cholesterol level. For patients taking the medication Coumadin (blood thinner), we provide a Coumadin Clinic, which supervises your Coumadin and blood levels. Your primary care provider will determine if an appointment with a cardiologist would benefit in the management of your problem. Our heart doctors will see patients age 18 and above.


Dermatology is the branch of medical science concerned with the physiology and pathology of the skin, hair, nails, and their related diseases. Your primary care provider will determine if an appointment with a dermatologist would be beneficial to further manage your healthcare needs.


  • Hypothalmus & Pituitary Disorders
  • Posterior Pituitary
  • Thyroid
  • Glucorticoids & Adrenal Androgens
  • Adrenal Medella
  • Endocrinology & Pregnancy
  • Diabetes & Pancreatic Hormones
  • Hypoglycemic Disorders
  • Obesity & Overweight
  • Multiple Endocrine Neomast
  • Geriatric Endocrinology

Endocrinology is the branch of medical science dealing with the endocrine or ductless glands and their functions and Diabetes. The endocrine system includes pituitary gland, thyroid gland, parathyroid glands, adrenal glands, Islets of Langerhans of the pancreas, hypothalmas, and the gonads (ovaries and testes).These are ductless glands that produce secretions, which are discharged into the blood and lymph system. Your primary care provider will determine if an appointment with our Endocrinology provider will be beneficial to further manage your health care problems.

Family Practice

David Shulman, M.D. Board Certified in Family Medicine
Arun Patel, M.D. Board Certified in Family Medicine
Rajnikant Patel, M.D.
Amandeep Singh, MD
Thayaparan Mathanakaran, M.D. Board Certified in Family Medicine
Rachel Walczyk, P.A.-C
Michael Presutti,P.A.
Candy Work, PA-C, RD, CDN.
Christa Zenoski, F.N.P.C.
Jenna Ring, F.N.P.C.
Sandy Jackson, F.N.P.C.
Kari Andera, F.N.P.C.
Mattison Baker, PA-C
Family Practice encompasses all ages, both sexes, and all diseases. Your Family Practitioner acts as the "gatekeeper" of your primary healthcare needs. Your provider will assist you in determining what care is necessary to meet your special circumstances, Wellness, Prevention, and Health Maintenance.

Gynecology Doctor and Obstetrics

Thaddeus Wojcik, M.D.
Roger Klein, M.D
Susan Dougherty, C.N.M., N.P.
Tamara Chaffee, C.N.M.</
  • Colposcopy
  • Cryotherapy
  • Menopause
  • Pelvic Pain
  • Pelvic Reconstruction
  • Sexual Dysfunction
  • Non-Stress Testing

Womens.Wellness.Logo.20.14Thaddeus Wojcik, M.D. is a gynecologist who deals with the management and care of diseases of the female reproductive organs, including the breasts. Roger Klein, M.D. rejoined our group in September of 2005. He specializes in infertility, normal and high risk pregnancy care, management of menopause and all gynecological conditions.  Annual care and screenings are important aspects of preventing and diagnosing potential problems. Annual care and screenings are important aspects of preventing and diagnosing potential problems. Your gynecology specialist serves all of Olean, NY and the surrounding areas.

Internal Medicine

William Cihak, M.D.
Gilbert Witte, M.D.
Donna Oehman, M.D.

Rajan Gulati, MD
Kelly Rice, D.N.P.
Christine Wild, A.N.P.C.
Ryann Taylor, A.N.P.C.
The practice of Internal Medicine is dedicated to adult healthcare and serves as your "primary care provider." Preventative medicine is a focus, but your PCP can also assess and treat acute and chronic healthcare problems. Depending on your condition, your physician may need to refer you to one of the specialists at Olean Medical Group or in the community.

Hematology and Medical Oncology

John Weinhold, Jr., M.D. Board Certified in Hematology and Medical Oncology
  • Breast Cancer
  • Lung Cancer
  • Colorectal Cancer
  • All other types of Cancer
  • Solid Tumor
  • On-site Chemotherapy
  • Phlebotomy
  • Mediport
  • Iron Infusion

Oncology is the branch of medical science which specializes in the diagnosis, management, and treatment of cancerous diseases. Broadly, cancer is an unregulated, disorganized growth of cells within the body due to many causes. This abnormal growth causes problems with surrounding normal tissues and structures. Hematology deals with diseases of the blood and the blood forming tissues. OMG offers procedures such as bone marrow aspirations and phlebotomy draws which aid in diagnosing and treating associated conditions. Your primary care provider will determine if an appointment with an Oncologist or Hematologist would be beneficial to your care. Our local cancer doctor, Dr. Weinhold will see patients 18 & up with occasional exceptions for benign hematology.


Othoniel Castro, M.D.,
Laura Pecorella, R.P.A.C.
Tests available on site: • EEGs (routine) • EMGs o Lumbar Puncture (need consult from Neurologist first) • Myobloc o Vagus Nerve Stimulation • Treat Tics • Treat Seizures • Treat Migraines
Neurology is the branch of medical science that deals with the nervous system and its associated diseases. The nervous system includes the brain, spinal cord and the nerves associated with those structures. Diseases and symptoms treated include alzheimers, migraine, seizures, strokes and more. Dr. Castro will see patients age 18 and above, but will see all ages for seizures, headaches and tic/tourettes.


Your neurological condition may necessitate an appointment with a Neurosurgeon, a surgeon who operates on the nervous system. The Olean Medical Group facilitates this service for you by arranging for 3 different Neurosurgeons from outside the Olean area to rotate services here on a monthly basis. Your healthcare provider will determine if an appointment will assist in managing your condition. Our nursing staff will facilitate this appointment for you.


Ricardo Ilustre, M.D.
Pamela Salzmann, D.O. 
Nichole Green, R.P.A.
Marti Brotka, F.N.P.
Tests available on site:

  • Audiograms
  • Developmental Testing
  • Peak Flow Meters
  • Tympanograms
  • Vision Testing
  • Immunizations

Pediatrics is the branch of medicine dealing with the care of infants, children and adolescents and treatment of their associated diseases. Your pediatric doctor acts as your child's primary care provider, assisting to oversee and evaluate his or her growth and development, as well as assess and render treatment for both acute and chronic childhood diseases.

Pediatric Cardiology

The Olean Medical Group is pleased to work in collaboration with Children's Hospital of Buffalo to offer the service of Pediatric Cardiology. Every third Friday of the month, Dr. Joseph Orie provides pediatric patients with cardiology services in our Olean office.

Pediatric Gastroenterology

WNY Pediatric Gastroenterology provides comprehensive care for infants, children and adolescents with gastrointestinal, liver and nutritional disorders in a compassionate and friendly environment.

For your convenience, their board certified physicians have an office here at our main site, every other Thursday in AREA F, 2nd floor.


Tressa Jordan, D.P.M - Foot and Ankle Care

Podiatry is a branch of medicine devoted to the study and diagnosis of any foot and ankle disorders. This specialty practice focuses on the wide variety of disorders, infections, injuries, and deformities of the affected area. A primary care provider will determine the severity of each case and recommend an appointment with a foot doctor or not based on your needs.


Gilbert Witte, M.D. Board Certified in Pulmonology and also in Critical Care Tests available in site:

  • Methocholine Challenge (requires consult with pulmonologist first)
  • Pulmonary Function Testing
  • Pulse Oximetry

Dr. Gilbert Witte has been Pulmonologist at OMG for 28 years, specializing in the evaluation and treatment of diseases of the lungs. The primary function of the lungs is to bring air and blood into contact so oxygen can be added to the blood and carbon dioxide can be removed. He treats asthma and COPD.Your primary care provider will determine if an appointment with a Pulmonologist would be beneficial in managing your care. Dr. Witte will see patients age 18 and above.


Rheumatology is an area of medicine that deals with both the male and female immune system. The body's immune system can be attacked through your joints & nerves as well as be effected from autoimmune diseases like Lupus & server inflammation. Your primary care provider will determine if an appointment with rheumatology doctor would be beneficial to further manage your healthcare needs.



Rajkumar Jeganathan, M.D. Board Certified in Surgery
Kathryn Nelson, PA-C


Urology deals with both the male and female urinary tract, and the male genital tract. The urinary tract includes the kidneys, bladder, ureters, and urethra. Your primary care provider will determine if an appointment with a urologist would be beneficial to further manage your healthcare needs.

  • IVPs
  • Impotence testing and treatment
  • Infertility Evaluations
  • Stress Incontinence (females)
  • Ultrasounds
  • Uroflowmetry