letrozole

letrozole /let·ro·zole/ (let´rah-zōl) an antineoplastic used in the treatment of advanced breast cancer in postmenopausal women.

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let·ro·zole (ltr-zl)

n.

A nonsteroidal aromatase inhibitor drug used to treat breast cancer in postmenopausal women.

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letrozole,

an antineoplastic nonsteroidal aromatase inhibitor.

indication It is used to treat metastatic breast cancer in postmenopausal women.

contraindications Known hypersensitivity and pregnancy prohibit its use.

adverse effects Hepatotoxicity is a life-threatening effect of this drug. Other adverse effects include dyspnea, cough, constipation, heartburn, diarrhea, alopecia, sweating, hot flashes, hypertension, somnolence, dizziness, depression, and anxiety. Common side effects include nausea, vomiting, anorexia, rash, pruritus, headache, and lethargy.

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letrozole Warning - Hazardous drug!

Femara

Pharmacologic class: Aromatase inhibitor

Therapeutic class: Antineoplastic

Pregnancy risk category D

Action

Inhibits aromatase, an enzyme that promotes conversion of estrogen precursors to estrogen. This inhibition reduces circulating estrogen levels and stops progression of breast cancer.

Availability

Tablets: 2.5 mg

⊘Indications and dosages

➣ Metastatic or advanced breast cancer in postmenopausal women; early breast cancer in postmenopausal women who have received 5 years of antiestrogen therapy

Adults: 2.5 mg P.O. daily

Contraindications

• Hypersensitivity to drug or its components

Precautions

Use cautiously in:
• severe hepatic impairment
• pregnant or breastfeeding patients
• children (safety not established).

Administration

• Give with or without meals.

Route	Onset	Peak	Duration
P.O.	Unknown	2-3 days	Unknown

Adverse reactions

CNS: anxiety, depression, dizziness, drowsiness, fatigue, headache, vertigo, asthenia

CV: chest pain, hypertension

GI: nausea, vomiting, diarrhea, constipation, abdominal pain, dyspepsia, anorexia

Metabolic: hypercalcemia

Musculoskeletal: musculoskeletal or joint pain, fractures

Respiratory: cough, dyspnea, pleural effusion

Skin: alopecia, pruritus, rash, diaphoresis

Other: hot flashes, edema, weight gain

Interactions

Drug-diagnostic tests. Cholesterol, gamma-glutamyltransferase: increased levels

Patient monitoring

• Check vital signs and assess cardiovascular and respiratory status.
• Monitor renal and hepatic function, electrolyte levels, and lipid panels.
• Assess for adverse CNS effects, including depression. Institute safety measures as needed to prevent injury.

Patient teaching

• Tell patient she can take with or without food.
• Instruct patient to weigh herself regularly and report significant changes.
• Advise patient and family to watch for signs and symptoms of depression.
• Tell patient to minimize GI upset by eating small, frequent servings of healthy food and drinking plenty of fluids.
• Caution patient to avoid driving and other hazardous activities until she knows how drug affects concentration and alertness.
• Inform patient that treatment is long term. Urge her to keep follow-up appointments with prescriber.
• Tell patient to inform prescriber if she is pregnant or breastfeeding.
• As appropriate, review all other significant and life-threatening adverse reactions and interactions, especially those related to the tests mentioned above.