Kenalog and one year later

Took my 2 sons, ages 14 & 8 for poison ivy treatment. Both were given Kenalog injections. We were not told of any possible side effects. One year later, they both have HUGE pits in their injections sites. We did not make the connection until my 14 year old went again and was given another shot. Now he has 2! The first one is about the size of a plum and about 1 inch deep! He is very self-conscious about this and the discoloration is very noticable. I am furious and wondering what can be done about this!