Did yoy guys culture and do a sensitivity test?

More often than not Pseudomonas is a factor in RI's and the med chosen isnt effective on Pseudomonas.

Most meds are IM but some are SQ like what your doing

Id follow the vets orders

How much are you injecting into the animal? Can you split the injection sites up so less is going into each spot?

Where are you injecting as well?