My husband took Amoxycillin after a Root Canal- Woke up with his face swollen like a balloon, the following day swollen all over with light occasional itching, fatigue and a slight pinkish skin rash. Immediately stopped Amoxycillin and took Benadryl, drank ALOT of water and went in for a steroid shot. I'm posting this the evening before shot. I certainly hope we begin to see some relief.