Episode 083: Pharmacology 101: Capstone (REBOOT!)
In the final episode in our reboot of Pharmacology 101, we sit down with Renee McAlister, PharmD, BCOP to learn more about the nuances of pharmacology from an expert that does this day in and day out.
Pharmacology Capstone:
Irritant vs. Vesicant:
For extravasation, what to do?
Not a great general source; would recommend checking institutional guidelines.
Different drugs may require a cold vs. warm compress.
Some drugs have antidotes - it is best to just look this up when it happens
Why is there a “cut off time” to get in chemotherapy orders?
Many hospital pharmacies are not 24 hours, therefore need prep time.
Many drugs take a long time to prepare!
A lot verification goes into ensuring that the drugs are correctly ordered, prepared, and handled. Therefore this requires adequate staff to do this safely.
What does "ideal body weight” mean?
Calculated by the patient’s sex, height, and the calculated body weight based on this information
Helps with drug-dosing to ensure that drugs are not over/under-dosed
What does “AUC” mean?
Incorporates renal function and the amount of exposure you want the patient to have to the drug. Based on the Calvert equation.
It is important to re-calculate each time with a new Cr to ensure that this is updated.
Example: https://reference.medscape.com/calculator/169/carboplatin-auc-dosing-calvert
What is the role of granulocyte colony-stimulating factor (GCSF)?
Helps to prevent the risk of infection, especially from endogenous bacteria.
GCSF helps to minimize the window of neutropenia related to treatment with chemotherapy
NCCN guidelines (www.nccn.org) provides guidelines about febrile neutropenia risk. A risk >20% means that we build in GCSF administration into the treatments.
If risk 10-20% with certain risk factors, we may consider adding GCSF
Always look at the paper that was what the approval of the regimen was based off of - they will comment on if/how GCSF was used during the study.
If patient develops neutropenic fever during a cycle, if even the drug is not traditionally one that we consider GCSF for, it would be appropriate to consider GCSF for future cycles to decrease the risk of febrile neutropenia.
What are the different “types” of GCSF?
Examples:
Filgrastim (“Neupogen”) - daily dosing, short-acting GCSF
Pegylated-filgrastim (“Neulasta”) - don’t have to give daily dosing; one time shot because it lasts for longer
On-body injector (OBI) - a device put on the arm that delivers pegylated- filgastrim at approximately 26 hours after chemotherapy
Dosing:
Very different dosing for all of these medications; pay attention to the dosing!
Supportive care:
How do you decide what anti-emetics to include?
NCCN supportive care guidelines is a great place to start
Regimens with >90% emetic potential should get at least three agents (for example: ddACT, cisplatin based regimens)
Example: 5-HT3 receptor antagonists, dexamethasone, olanzapine, and aprepetant
Moderate emetic potential (30-90%), add at least 2 drugs
Example: 5-HT3 receptor antagonists and dexamethasone
Lower risk (30%): usually one one drug
Example:5-HT3 receptor antagonists
If patients have refractory nausea in a cycle, add another agent. When adding drugs, always ensure you are incorporating the patient’s other medical history AND drug-drug interactions
Pharmacists are an amazing source of information! Please reach out with questions!
