Weight Loss in Amarillo, TX 79106 Amarillo, Texas 79106 Provider: Female Serves: Amarillo. If you live more than 50 miles from Amarillo, you cannot use Walgreens for a phentermine prescription. Available: Mon, Tues, Thurs, Fri (Some Evenings) & Occasional Saturday Appts. Enroll as a New Patient Here is What Our Patients Are Saying