Prostate/Colon Cancer Pharmacology

Contraindications for capecitabine

Severe bone marrow suppression, liver impairment, DYPD gene, pregnancy, breastfeeding, kidney impairment. 

Usage of capecitabine

Rectal cancer, colorectal cancer, HER-2 overexpressing gastric or gastroesophageal cancer, pancreatic cancer. 

Mechanism of action of capecitabine

Coverts to active 5-FU, which causes cellular injury by interfering w/DNA synthesis, RNA processing, and protein synthesis. 

Side effects of capecitabine

Fatigue, weakness, nausea, vomiting, diarrhea, and stomach pain. 

Nursing interventions for capecitabine

• Monitor PT and INR  

• Monitor fluid and electrolytes 

• Monitor CBC (WBC, platelets) 

• Monitor for S/S cardiotoxicity 

• Monitor for S/S hand-foot syndrome 

Contraindications for leucovorin

Pernicious anemia, lacking B12, liver disease, kidney disease, dehydration, difficulty breathing.  

Usage of leucovorin

Reduce toxic effects of certain meds, support cancer therapies, and treat folate deficiency. 

Mechanism of action of leucovorin

Aids in production and maintaining new cells, also prevents changes in DNA that may lead to cancer. 

Side effects of leucovorin

Nausea, vomiting, diarrhea, stomach pain, loss of appetite 

Nursing interventions for leucovorin

• GI assessment 

• Labs (folic acid) 

• Monitor fluid and electrolytes 

Contraindications for fluorouracil (5-FU)

Pt’s who have received high-dose pelvic radiation, alkylating drugs, impaired kidney or liver function, pregnancy, and breastfeeding. 

Usage of fluorouracil (5-FU)

Colon and rectal adenocarcinoma, gastric adenocarcinoma, esophageal cancer, pancreatic adenocarcinoma. 

Mechanism of action of fluorouracil (5-FU)

Interferes with DNA and RNA synthesis, which affects rapidly growing cells, may lead to cell death. 

Side effects of fluorouracil (5-FU)

Diarrhea, mouth sores, heart problems, and bone marrow suppression. 

Nursing interventions for fluorouracil (5-FU)

• Withhold drug if S/S of toxicity are present 

• Monitor for bleeding 

• Monitor CBC (platelets) 

• Monitor I/O 

• Expect a blood transfusion 

Generic names for antiandrogens

enzalutamide, apalutamide  

Contraindications for antiandrogens

High seizure risk, high fall risk, PRES, unprotected intercourse. 

Usage of antiandrogens

Castration-resistant prostate cancer, castration-sensitive prostate cancer. 

Mechanism of action of antiandrogens

Inhibits androgen binding at multiple levels on the androgen receptor signaling pathway, leading to cell apoptosis and decreased tumor volume. 

Side effects of antiandrogens

Fatigue, weakness, constipation, diarrhea, flushing, joint/back pain, high BP 

Nursing interventions for antiandrogens

• Monitor for seizure activity 

• Monitor for S/S PRES 

• Monitor for S/S of heart disease 

• CBC 

• CV assessment 

Contraindications for oxaliplatin

Kidney impairment, peripheral sensory neuropathy, CV disease, long QT syndrome, pregnancy, breastfeeding 

Usage of oxaliplatin

Gastric cancer, esophageal cancer, pancreatic cancer, colon cancer or colorectal cancer 

Mechanism of action of oxaliplatin

Inhibits cell replication and transcription by forming platinum complexes that cross-link w/DNA molecules. 

Side effects of oxaliplatin

Nausea, vomiting, diarrhea, fatigue, mouth sores, S/S neuropathy, low WBC, RBC, and platelets. 

Nursing interventions for oxaliplatin

• Monitor kidney function 

• CBC, platelet count, LFT 

• Review ECG 

• Electrolytes and fluid 

• S/S of PRES, neuropathy, pulmomary toxicity 

Generic names for EGFR inhibitors

cetuximab, panitumumab 

Contraindications for EGFR inhibitors

Red meat allergy, history of tick bites, pregnancy, breastfeeding, skin conditions, ocular disease. 

Usage of EGFR inhibitors

ECFR-expressing colorectal cancer, wild-type RAS colorectal cancer 

Mechanism of action of EGFR inhibitors

Binds to EGFR on cells, inhibiting cell growth, decreasing vascular endothelial growth factor production, inducing cell death. 

Side effects of EGFR inhibitors

Itching/rash, dry skin, headache, diarrhea, infection, changes in nails, mouth sores, fatigue, nausea, loss of appetite 

Nursing interventions for EGFR inhibitors

• Prep for infusion reactions 

• CV assessment 

• Monitor for skin toxicity 

• Fluid and electrolytes 

• S/S acute kidney failure 

• S/S pulmonary toxicity 

Contraindications for bevacizumab

Ovarian cancer, history of thromboembolism, older adults, history of anthracycline-based chemotherapy, pregnancy, breastfeeding 

Usage of bevacizumab

Colon or rectal cancer paired w/5-FU or oxaliplatin 

Mechanism of action of bevacizumab

Inhibits vascular endothelial growth factor. 

Side effects of bevacizumab 

Increased BP, headache, back pain, dry or watery eyes, dry skin, stuffy or runny nose.

Nursing interventions for bevacizumab

• CV assessment 

• Monitor for S/S internal bleeding 

• S/S PRES 

• GI assessment 

• Urinalysis and CBC 

Generic names for LHRH antagonists

degarelix, relugolix 

Contraindications for LHRH antagonists

Congenital long Qt syndrome, electrolyte abnormalities, HF, liver impairment, pregnancy, breastfeeding 

Usage of LHRH antagonists

Advanced prostate cancer. 

Mechanism of action of LHRH antagonists

Binds to and antagonizes GnRH receptors, which reduces release of gonadotropins and, consequently, testosterone. 

Side effects of LHRH antagonists

Hot flashes, weight gain, injection site irritation, fatigue, joint pain, anemia. 

Nursing interventions for LHRH antagonists

• Monitor QT interval 

• Electrolyte balance 

• PSA and testosterone level 

• LFT (liver impairment pt’s) 

• Bone density tests 

Why does capecitabine have a BBW? 

May decrease warfarin clearance, increases bleeding risk, monitor PT and INR levels. 

When a patient receives 5-FU via IV, they should be _ for their initial treatment. 

Hospitalized 

What is oxaliplatin usually paired with? 

5-FU and leucovorin 

Why does oxaliplatin have a BBW? 

Fatal hypersensitivity reactions, increased risk of neuropathy when exposed to cold conditions. 

Why does cetuximab and panitumumab have a BBW? 

Fatal infusion reactions, closely monitor if used with radiation of 5-FU. Dermatologic toxicity is very common (90%).