Primary Care Internal Medicine and Medical Subspecialties

Welcome to Amarillo Medical Specialists.

Amarillo Medical Specialists is the largest private practice Internal Medicine group in the Texas Panhandle. We are focused on providing a patient centered approach, and we want to be your 'Medical Home'.


AMS welcomed  Kalil Al-Nassir, MD, FACP, FCCP  for the practice of Pulmonary Medicine at 1215 Coulter St, Suite 204, starting in April 2019.  All patients who need pulmonary care are welcome, however please check with our office to see if your insurance company has updated their provider list to include Dr. Al-Nassir.  

Dr Al-Nassir is in network with Medicare, Blue Cross, IMS, Cigna, United, Aetna, FirstCare, Railroad Medicare, Prominence Medicare, and many other plans.

Appointments can be scheduled by calling (806) 677-2030. If your insurance company has not yet updated their records to include Dr. Al-Nassir, we will maintain a wait list and notify you when we get the green light from your company. 


AMS is welcoming Amy Brasher, FNP to Dr. Estelle Archer's practice at 1900 Coulter, starting on July 9, 2018.  Amy will be practicing General Medicine for men and women, for patients age 6 and up. New and existing patients are welcome!

1900 S. Coulter Street, Suite H

Phone: (806) 350-2389

Fax: (806) 356-0045



In October 2017 we welcomed Dr. Kathryn McNeil in Psychiatry.


Kathryn McNeil, MD is starting our new Psychiatry department, and is joining us after teaching at Texas Tech Medical School in Amarillo. She is a graduate of Rice University in Houston, and Texas Tech School of Medicine in Lubbock.  She was trained at the University of Arizona in Psychiatry, and has taught Psychiatry at both the University of Arizona and Texas Tech. her practice opens October 2, 2017. Appointments are being made now. Dr. McNeil accepts Medicare as well as most commercial insurance plans. Appointments can be scheduled by calling (806) 677-7603.


TEXAS MONTHLY MAGAZINE has honored thirteen AMS physicans by their inclusion on the 2018 or earlier Super Doctors ® lists. This comes with the additions of Dr Christopher Gulley, and Dr. Ako Bradford, who were chosen by Texas Monthly for the 2018 and 2014 'SuperDoctors Rising Star' list respectively.  Amarillo Medical Specialists now has the largest number of Internal Medicine doctors included on the Super Doctors list of any group in the region. 

Congratulations to: Dr Milton Giron,    Dr Georges Maliha (Kidney Disease),  Dr Alan Keister (Internal Medicine) and Drs. Stephen J Usala, Kenny M Brantley ,Susan Wingo & William C. Biggs (Endocrinology and Diabetes), and Dr. Janet Schwartzenberg (Rheumatology) for their inclusion in the 2018 Texas SuperDoctors listing.

Dr. Christopher Gulley was included in the 2018 Texas SuperDoctors Rising Star list.

Drs. Schwartzenberg, Usala & Biggs have been each been honored for 12 or more years.

In previous years, Dr. Lawrence Schaeffer (Neurology), Dr. Ed Dodson (Endocrinology)  and Dr Jesus Sahad (Pulmonary Medicine) have also been included on the Texas Monthly Super Doctors list, and Dr. Ako Bradford (Primary Care Medicine) has been listed as a Texas Monthly Rising Star.

 Now we're on Facebook too....

If you are new to our office, and have already scheduled an appointment, then check out the 'New Patient Pages' to the left.

If you are looking for a doctor, we have information on most of our doctors to the right side of your screen. We invite you to call directly to the doctors office to schedule an appointment.


If you are looking for our most popular page, 'How to review your lab test results" , it is available at .

In a hurry for a new patient appointment?

Here are the doctors with the shortest wait times for a new appointment:

Primary Care /Internal Medicine:  Nam Do, MD (806) 355-9741

Pulmonary Medicine : Kalil Al-Nassir, MD FACP FCCP  (806) 677-2030

Psychiatry : Kathyrn McNeil, MD  (806) 677-7603

Gynecology:  Estelle Archer, MD  (806) 350-7312

Endocrinology/Diabetes: William C Biggs, MD FACE (806) 358-8331 and Cesar Arias MD FACE (806) 677-2030

Nephrology: Milton Giron MD, and Tarek Naguib MD (806) 358-8477

The information contained on this site is for general health information only. It is not medical advice. Never substitute any information or advice from the Internet for bona fide health care. You should consult with your personal doctor before undertaking any action based on information or advice found here or elsewhere on the Internet. Please see our legal notice for more information.



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