Gastroenterology Associates, L.L.P.
1249 Ambler Ave
Abilene, TX 79601
(325) 677-2626

Meet the Doctors

All of our doctors at Gastroenterology Associates are Board Certified in Internal Medicine and Gastroenterology.

William C. Haynes, M.D.
A true West Texan, Dr. Haynes was raised in Merkel where watching his grandfather, Dr. Sadler practice medicine, he was influenced to become a physician.  He graduated from Cooper High School in Abilene.  He obtained his medical degree from the University of Texas Medical Branch at Galveston and continued with training internal medicine.  He attended the University of Arizona Veterans Administration Medical Center in Phoenix, Arizona.  

Gary Roark, M.D.
Born in Graham, Texas, Dr. Roark received his medical degree from the University of Texas Medical Branch in Galveston and also his internal medicine.  His Gastroenterology fellowship was at the University of Utah.  He was Assistant Professor of Internal Medicine at the University of Texas Medical Branch.

Iliana J. Carpenter, PA-C, MPAS
Born in El Salvador, Mrs. Carpenter received her undergraduate degree from Abilene Christian University and PA degree from the University of Texas Medical Branch. She came back to Abilene in 2016 from Duke Medical Center in Durham, NC.

Mrs. Carpenter has been practicing as a Physician Assistant for over 24 years. She speaks fluent Spanish and English.


Avery L. Smith, M.D. 

A native of West Texas, Dr. Smith was raised in Midland. He graduated from Midland High School and obtained his undergraduate degrees at Midland College and the University of Texas of the Permian Basin. Afterwards, he obtained his medical degree from Texas A&M College of Medicine. He completed his residency in internal medicine and fellowship in gastroenterology & hepatology at Baylor University Medical Center in Dallas. 

He is excited to be moving to the area with his wife, Shelby, and daughter, Adley, to provide care to the people that made West Texas feel like home.