Hives after Botox injections
First, please understand that nobody is born allergic to anything.
A person may become allergic to a substance (Poison ivy, Nickel,etc) or a drug (Penicillin, Sulfonamide,etc) after prolonmged, repeated exposure, The lists can be endless.
As to your reaction to Botulinum Toxin: Botox contains a toxin fraction and a protein fraction. You can become allergic to either or both. The same is true for the newer Dysport.
I would be very careful with further injections of Botox in...