I am hopefully getting over 3 cases of RI. They all have been to the vent and have been prescribed Ceftazidime. My vet said they will always be more susceptible to RI's even when there completely healed. My question to you is out of how many snakes you have treated with an RI relapse months maybe years down the road and how often do they? Also wondering if those snakes were immune to the previous medication or dosage.