To make an appointment, please call (661) 471-4400 Monday – Friday 8:00 a.m. – 4:30 p.m. or self-schedule in the LA Health Portal found here. For more information, click here www.vaccinatelacounty.com or call 211. High Desert Regional Health Center (HDRHC) is a new, modern ambulatory care clinic located on Avenue I, in central Lancaster..