Fever Blisters After Juvederm Lip Injections

Cold sores or fever blisters (which are actually herpses simplex infections) are viral in origin. The virus lives along your spinal column and is kept in check by your immune system. But at times of stress or trauma (eg. a filler lip augmentation), the virus can overcome your immune system and produce an outbreak. If you have any history of previous HSV outbreaks, make sure your provider knows about it so that appropriate anti-viral therapy can be initiated.
I hope that helps!

Fever blisters typically recur because of pain, trauma, change in temperature or any number of other reasons. I always ask my patients if they've ever had an outbreak before I perform any injections of the lips. I'm sure to start them on Valtrex immediately then maintain the Valtrex for up to a week after just to be on the safe side.