Emcyt


estramustine

(es-tra-mus-teen) estramustine,

Emcyt

(trade name)

Classification

Therapeutic: antineoplastics
Pharmacologic: alkylating agents
Pregnancy Category: UK

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 effects

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)

ROUTEONSETPEAKDURATION
PO30–90 daysunknown6 wk†
†Persistence of hematologic effects

Contraindications/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

Central nervous system

  • insomnia

Cardiovascular

  • thromboembolism (life-threatening)
  • edema (most frequent)
  • hypertension

Gastrointestinal

  • diarrhea (most frequent)
  • nausea (most frequent)
  • anorexia
  • flatulence
  • vomiting

Dermatologic

  • bruising
  • dry skin
  • pruritis
  • rashes

Endocrinologic

  • decreased libido (most frequent)
  • gynecomastia (most frequent)
  • gonadal suppression (azoospermia)
  • hyperglycemia

Hematologic

  • leukopenia
  • thrombocytopenia

Musculoskeletal

  • leg cramps

Respiratory

  • dyspnea (most frequent)

Miscellaneous

  • angioedema (life-threatening)
  • allergic reactions

Interactions

Drug-Drug interaction

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

Route/Dosage

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

Availability

Capsules: 140 mg

Nursing implications

Nursing 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 Nursing Diagnoses

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

Implementation

  • Oral: 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.