Lip waxing might be approved by the doctor performing your Ultherapy for the next day, however, if there was the utilization of the 1.5 mm. superficial transducer, and if welts had occurred and persist, then the skin might be more susceptible to injury by the waxing. Please be sure to check with the provider, after you have the Ultherapy as to when you can have the waxing.
The information provided in Dr. Shelton's answer is for educational purposes only and is not intended to constitute medical advice. The information provided should not be relied upon as a substitute for consultations with a qualified health professional who may be familiar with your individual medical needs.