CHAMPVA is managed by the VA's Health Administration Center. You can call us at 800-733-8387, Monday through Friday from 6:05 a.m. (Mountain Tme) until 5:30 p.m. (Mountain Time). Any calls in the queue at 5:30 p.m. (Mountain time). The best matching results for Champva Provider Portal Registration are listed below, along with top pages, current status, and comments. If you are facing any issues, please write detail in the comments section for the solution. Updated: April 23, 2022. Dr. Mario Juarez, MD. 7 mi. Primary Care Doctor. 4151 Callaghan Rd, Ste 102, San Antonio, TX 78228. 4.20. 292 verified reviews. Dr. Mario Juarez is a kind, compassionate, and detailed oriented doctor offering both Primary Care and Medical Spa services. Board Certified in Family Medicine and a graduate of the prestigious Southwestern Medical.