Is it safe to have local anesthesia for an endoscopy and a lip filler appointment on same day four hours apart?

If you are having a gastrointestinal endoscopy then those are usually done under conscious sedation whereas you are being put to sleep and rarely involve usage of topical anesthetics such as Lidocaine, So in this regard you should be ok , but I would still recommend rescheduling your filler appointment for another day since the effect of sedation might be lingering for more than four hours. At least I would not be comfortable injecting your lip if you were still sedated to any degree. However, if you and your doctor decide that it's worth doing it the same day, then injecting lips should not be involving a significant amount of local anesthetic (whether injected or used as a topical) , but do bring your endoscopy anesthesia records with you and let your doctor decide the safety protocol.

While it is always smart to separate procedures, technically if you get filler before your endoscopy it should be okay.  If your endoscopy is first, you might be sleepy from anesthesia they give. If you can wait do so.  But if you want it then make sure you have help with transportation.  Good luck.