Vigilance, Rapid Interventions Key to Chemotherapy Reaction Management

Desensitization Protocols

Desensitization involves gradually and slowly reintroducing a chemotherapy agent to a patient under close observation, starting with very low chemotherapy agent doses and premedications that help control immune reaction. For example, premedications for oxaliplatin desensitization include diphenhydramine (Benadryl; 25 mg IV) or dexamethasone (Decadron; 20 mg IV).

The infusion doses begin at 1/10,000 or 1/1000 of the total prescribed dose and are incrementally increased. In the case of inpatient oxaliplatin desensitization, for example, the schedule is 1/10,000 of total dose for 1 hour, followed by 1/1000 of dose for 1 hour, 1/100 of dose for 1 hour, and 1/10 of dose for 1 hour, then the remainder of the total oxaliplatin dose over the next 4 hours, Price explained.

Desensitization should be undertaken with all future doses of the chemotherapy agent that triggered the reaction. It is not always successful and entails a risk of reaction recurrence, but can, when successful, preserve the chance to administer a potentially life-saving chemotherapy.

“It’s not just a once and done,” Price said. “The patient is always going to require desensitization going forward if they are getting that particular drug, done in a controlled environment with emergency equipment available. So have a code cart available and we have all of the meds we might need.”

Importantly, contraindications to desensitization infusions include an extreme allergic response such as Stevens-Johnson syndrome or reactions involving skin desquamation or erythema multiforme (symmetric red, raised skin rash), Price said.

Being able to distinguish between the different reaction types, to grade them, and to intervene quickly are key, Price emphasized. “Remember, grading is essential in helping us to determine is this a mild reaction and maybe we can just challenge with some additional meds and additional premeds, or is it more severe and we need to consider desensitization?”

Reference

Price M. Reactions and desensitization. Presented at: ONS Bridge; September 12, 2023.