Pharmacology Flashcards
What does it mean to use a cell cycle specific chemotherapeutic drug, and what does the response depend on?
Requires the cell to be in a certain part of the cell cycle to be effective
Response depends on exposure time and frequency of administration
What does it mean to use a non-cell cycle specific chemotherapeutic drug, and what does the response depend on?
Requires a cell to be dividing (regardless of phase)
Response is concentration dependent
What is drug dosing based on?
BSA, AUC (area under the curve), and weight
What are the four main principles of combination chemotherapy?
Drugs are known to be active as single agents
Drugs with different MOA, dose limiting toxicities (two drugs with the same side effects), and patterns of resistance
What are some principles of dose intensity when using combination chemotherapy?
Dose escalation (increase as tolerated) Dose density (minimize toxicity) Sequential timing of single agents
What are three important factors that affect patient response to chemotherapy?
Drug resistance- altered membrane transport, decreased activation or degradation.
Drug interactions-pharmacokinetics and dynamics
Host factors-kidney or liver impairment, comorbidities
What are the calculations of Body surface area (BSA) and area under the curve (AUC)?
BSA =square root (kg x cm)/3600. weight x height
AUC= (CrCl + 25) CrCl is creatine clearance (calvert equation)
What are some guidlines for chemotherapy saftey?
No verbal orders At least a second check of orders Standardized order forms. Clearly labeled medications Generic names used, NOT brand names
Platinum based therapy is the mainstay for lung cancer treatment. What’s a platinum doublet and which platinum drugs should you know?
The doublet is just a way to say “treat with 2 platinum drugs” sometime patients are treated with 3.
Cisplatin-high emetic risk (PREMEDICATION IS KEY), maintain good hydration.
Carboplatin- dosed based on AUC.
Oxaliplatin- used more in colorectal cancer
What are the major toxicities associated with the platinum chemotheraputic agents?
Cisplatin- seizure, encephalopathy, visual impairment, Hypersensitivity.
Carboplatin-visual impairment and hypersensitivity
Oxaliplatin- neuropathy, hemolytic anemia, pulmonary fibrosis, and hypersensitivity.
What chemotherapy drugs are microtubule inhibitors? What’s their MOA?
Taxanes which have the suffix taxel.
Paclitaxel
also Ixa-bep-ilone
MOA- cell cycle specific (G2/M phase)
Mitotic spindle poison
What are some common toxicities of paclitaxel?
Hypersensitivity reaction to the cremophor vechical used to make the drug soluble; the albumin bound paclitaxel solves this problem.
sinus bradycardia
Pulmonary embolism
Stevens-Johnson syndrome
seizure
What are some common toxicities of docetaxel?
Fluid retention: pre-medicate with dexamethasone
Pulmonary embolism
Stevens-Johnson syndrome
Colitis
In what order should you administer taxanes and platinum drugs?
Tax before plaques, but after anthrac-cycline
If you don’t you get more neutropenia (decreased PMNs)
Describe a topoisomerase, name one type of inhibitor for Topoisomerase I & II, describe it’s MOA and side effects.
I-rino-tecan (small cell lung cancer)
MOA- topoisomerases release stress of DNA torsion, so without them the strands break.
Topoisomerase I inhibition. This is a cell cycle specific drug (S phase).
Topoisomerase II inhibition (G2 phase).
Side effects- DIARRHEA. From damage to intestinal tract lining. GI perforation Interstitial lung disease DOSE LIMITED MYELOSUPPRESSION
Camptothecins inhibit what?
topoisomerase
