General

Pronunciation:
es-tra-mus-teen

Trade Name(s)

• Emcyt

Ther. Class.

antineoplastics

hormones

Pharm. Class.

alkylating agents

Indications

Palliative treatment of advanced metastatic prostate cancer.

Action

• Consists of combination of mechlorethamine, an alkylating agent, and estradiol, an estrogenic compound. Antineoplastic activity may be due to either component or the combination.
• Also decreases serum testosterone levels.

Therapeutic Effect(s):

Decreased spread of prostate cancer.

Pharmacokinetics

Absorption: Well absorbed (75%) after oral administration. During absorption, converted to estramustine, estromustine and then to estrogenic compounds (estrone and estradiol).

Distribution: Concentrates in prostatic tissue.

Metabolism and Excretion: Eliminated primarily by biliary and fecal excretion. Small amounts excreted by kidneys.

Half-life: 20–24 hr.

TIME/ACTION PROFILE (effect on tumor spread)

Contraindication/Precautions

Contraindicated in:

• Active thrombophlebitis or thromboembolic disorder
• Known hypersensitivity to estradiol or mechlorethamine.

Use Cautiously in:

• History of thrombophlebitis or thromboembolic disorders
• Hypercalcemia
• Renal or hepatic impairment
• Coronary artery disease
• Hypertension
• Heart failure
• Diabetes mellitus
• Cerebrovascular disease
• Migraine headaches
• Metabolic bone disease
• Epilepsy
• Patients with childbearing potential.

Adverse Reactions/Side Effects

CNS: insomnia

CV: THROMBOEMBOLISM, edema, hypertension

GI: diarrhea, nausea, anorexia, flatulence, vomiting

Derm: bruising, dry skin, pruritis, rashes

Endo: decreased libido, gynecomastia, gonadal suppression (azoospermia), hyperglycemia

Hemat: leukopenia, thrombocytopenia

MS: leg cramps

Resp: dyspnea

Misc: ANGIOEDEMA, allergic reactions

* CAPITALS indicate life-threatening.
Underline indicate most frequent.

Interactions

Drug-Drug

 Calcium supplements  form an insoluble complex with estramustine that cannot be absorbed.

Drug-Food:

Calcium in dairy foods forms an insoluble complex with estramustine that cannot be absorbed.

Route/Dosage

PO (Adults): 14 mg/kg/day in 3–4 divided doses (range 10–16 mg/kg/day).

Availability

Capsules: 140 mg

Assessment

• Monitor BP periodically throughout therapy.
• Monitor intake and output ratios and weekly weight. Report significant discrepancies or steady weight gain.
• Monitor blood glucose closely in diabetic patients. May decrease glucose tolerance.

Lab Test Considerations:

Monitor hematologic and hepatic functions, serum calcium, and phosphorus periodically throughout therapy. May cause leukopenia and thrombocytopenia. May also cause elevated LDH, AST, and bilirubin levels.

• May cause increased serum glucose.
• May cause hypercalcemia in patients with metastatic bone lesions.

Potential Diagnoses

• Deficient knowledge, related to medication regimen (Patient/Family/Teaching) 

Implementation

• PO Administer with water 1 hr before or 2 hr after meals. Milk, milk products, and calcium-rich foods or calcium-containing antacids impair the absorption of estramustine and must not be taken simultaneously.
  • Frequently causes nausea and sometimes causes vomiting. Phenothiazines may be administered to treat nausea and vomiting. May require discontinuation of therapy.

Patient/Family Teaching

• Instruct patient to take estramustine exactly as directed. If a dose is missed, omit; do not take at all. Do not double doses. Notify health care professional if vomiting occurs shortly after a dose is taken. Do not discontinue without consulting health care professional.
• Instruct patient to store capsules in the refrigerator, but capsules may be kept at room temperature for 24–48 hr without losing potency.
• Advise patient and partner of the need for contraception throughout therapy, as sperm cells may be altered.
• Advise patient to report signs and symptoms of fluid retention (swelling of ankles and feet, weight gain) and thromboembolic disorders (pain or swelling in legs, tenderness in extremities, shortness of breath; headache; chest pain; blurred vision) to health care professional.

Evaluation/Desired Outcomes

Decrease in spread of prostate cancer. May require 30–90 days to determine maximum effects of therapy.