FULVESTRANT
| FULVESTRANT (ful-ves'trant) Faslodex Classifications: antineoplastic; hormone, antiestrogen; Therapeutic: antineoplastic; antiestrogen Prototype: Tamoxifen citrate Pregnancy Category: D |
Availability
50 mg/mL
Action
Fulvestrant is an estrogen receptor antagonist that selectively binds to the estrogen receptors (ER) of breast cancer cells. It competes well with estradiol (estrogen) in binding to these receptor sites. Estrogen stimulates the tumor growth of estrogen-sensitive breast tissue cancer cells in postmenopausal women.
Therapeutic Effect
In postmenopausal women, many breast cancers have estrogen receptors (ERs), and the growth of these tumors is stimulated by estrogen. Therefore, fulvestrant decreases estrogen-sensitive breast tissue tumor growth.
Uses
Treatment of hormone receptor-positive metastatic breast cancer in postmenopausal women with disease progression following antiestrogen therapy.
Contraindications
Hypersensitivity to fulvestrant; pregnancy (category D); lactation.
Cautious Use
Moderate to severe liver impairment; biliary disease; coagulopathy; anticoagulant therapy. Safety and effectiveness in children not established.
Route & Dosage
| Metastatic Breast Cancer Adult: IM 250 mg once/mo |
Administration
Intramuscular- Do not administer unless the possibility of pregnancy has been ruled out.
- Break the seal of the white plastic cover on the syringe luer connector to remove the cover with the attached rubber tip cap. Twist to lock the needle to the luer connector. Remove excess gas from the syringe (a small gas bubble may remain).
- Administer slowly in the buttock.
- Immediately activate needle protection device upon withdrawal from patient by pushing lever arm completely forward until needle tip is fully covered.
- Store in a refrigerator, 2°–8° C (36°–46° F) in original container.
Adverse Effects (≥1%)
Body as a Whole: Asthenia, pain, injection site pain, flu-like syndrome, fever, peripheral edema. CNS: Dizziness, insomnia, paresthesia, depression, anxiety. CV: Vasodilation. GI: Nausea, vomiting, constipation, diarrhea, anorexia. Hematologic: Anemia. Musculoskeletal: Bone pain, arthritis. Respiratory: Pharyngitis, dyspnea, cough. Skin: Rash, sweating.Pharmacokinetics
Peak: 7 d. Duration: 1 mo. Distribution: 99% protein bound. Metabolism: In liver via CYP3A4. Elimination: 90% in feces. Half-Life: 40 d.Nursing Implications
Assessment & Drug Effects
- Monitor for S&S of tumor progression.
- Lab tests: Monitor periodic CBC with differential.
Patient & Family Education
- Use two methods of contraception while taking this drug. Immediately notify physician if you think you are pregnant.
- Report vaginal bleeding to physician. Understand the possibility of drug-induced menstrual irregularities before starting treatment.
Common adverse effects in italic, life-threatening effects underlined; generic names in bold; classifications in SMALL CAPS; 
Canadian drug name; 
Prototype drug