Our Staff

At Mid-Cities Dermatology Clinic, we recognize that your choice of a dermatologist is driven both by the doctor's competency and personality. When searching for dermatological treatment, you need a dermatologist who is experienced, understanding and supportive. You get this caring attitude from all the staff at Mid-Cities Dermatology Clinic every day. Our staff works together as a team to be sure we are responsive to your needs and keep you informed about your health issues. We look forward to getting to know you.

John David Miller, M.D.

I am an adopted Texan. I was born in Oklahoma, but have been in Texas for the last 40 years. I attended the University of Houston from 1963-1966, and obtained my M.D. degree from the University of Texas Medical Branch at Galveston in 1970. I interned at Wilford Hall Medical Center in San Antonio; Texas. After my internship, I did General Practice for the Air Force in Austin, Texas (1971-1973) before returning to Wilford Hall for my specialty training. My residency in Dermatology was from 1973-1976; having completed my training I was assigned to the staff at Carswell AFB regional hospital from 1976-1977.

I have been in private practice in Dermatology in the Mid Cities since 1977. I am Board Certified and a Diplomat of the American Board of Dermatology. I am married, my wife’s name is Ann, and we have three married children; Katie,  Jeff and his wife Jenny and Matt and his wife Rachel, grandsons Nicholas, Matthew, Max, and Mason, and granddaughters Emilee, Libby, and Penny.

Dedication of my office
I wish to dedicate my office to my late mother, Virginia Miller. She was one of the most thoughtful, considerate human beings; and was instrumental in my becoming a physician. In her memory, I dedicate this office to provide the best dermatological care in her spirit of kindness and concern.


Caitlin E. Colosky, MPAS, PA-C

I was born in New York, moved to six different cities across the United States and finally landed in Texas. I grew up in the Dallas area and attended Southlake Carroll High School. Later I earned my Bachelor's degree in history from Princeton University while also taking pre-med courses. While at Princeton, I was on the Division I Ivy League championship women's swim team and qualified for the 2008 Olympic Trials in swimming.

I always knew I wanted to pursue a career in medicine and dermatology. I worked at Monmouth Family Health Center, Penn Oncology and Hematology Associates and volunteered at Children's Medical Center while in college. In the summer of 2010, I decided to embark on the journey to become a PA. I was admitted to the University of Texas at Southwestern, earned my master's degree in PA studies in 2015 and was inducted into the Pi Alpha Honor Society. I worked at Parkland Hospital as a PA in the hospitalist and internal medicine department for over one year and gained valuable experience treating acute and chronic illnesses, admitting patients from the ER and performing inpatient procedures. In May 2017, I decided to pursue my dream of working in dermatology and joined the Mid-Cities Dermatology Clinic. I am very blessed to have the opportunity to train and work alongside Dr. John David Miller. I am a Fellow member of the Society of Dermatology PAs and I am working on obtaining diplomate status through the SDPA fellowship program. I am also a member of the American Academy of PAs and Texas Academy of PAs. My interests in dermatology include acne, psoriasis, rashes, treating skin cancers and providing patient education.

I currently live in Dallas with my husband, Tom. My hobbies include traveling, weight lifting, cooking/baking, interior decorating and trying the newest restaurants in the Dallas area.


Alyssa Ilg

Alyssa Ilg is a certified Physician Assistant and is licensed to practice medicine in the state of Texas.

Alyssa was born and raised in Atlanta, Georgia. She received her bachelor's degree in Nutrition Science from the University of Georgia and then went on to pursue her master's degree in Physician Assistant studies from Augusta University. During her master's studies, she had clinical rotations in dermatology, which sparked her interest in the field. Upon graduating, Alyssa started working in dermatology in Augusta, Georgia seeing a wide range of dermatological conditions concerning the hair, skin, and nails. She then moved to Dallas in the fall of 2019 to be with her fiancé and began serving patients at Mid-Cities Dermatology Clinic in June of 2020.

Alyssa is a member of the Society of Dermatology Physician Assistants and is an SDPA diplomate.

During her free time she enjoys cooking, trying new restaurants, staying active, and traveling.