What Causes Swelling And Numbness On Lips After An Upper GI Endoscopy?

I had an upper GI endoscopy yesterday. I anticipated a sore throat, even sore spots on the throat. I did not anticipate my lower right lip being swollen and numb. I have looked to see what could be the issue and have notified the doctor s office, since the numbness has yet to go away. He thinks I bit my lip, but I have never had a numb lip from biting it before.