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Pharmacologic class: Aromatase inhibitor

Therapeutic class: Antineoplastic

Pregnancy risk category D


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


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


• Hypersensitivity to drug or its components


Use cautiously in:

• severe hepatic impairment

• pregnant or breastfeeding patients

• children (safety not established).


• Give with or without meals.

Adverse reactions

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

CV: chest pain, hypertension

EENT: blurred vision

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, angioedema, anaphylactic reactions


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.


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


A nonsteroidal drug, C17H11N5, that inhibits the enzyme aromatase and is used to treat breast cancer in postmenopausal women.


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.


An AROMATASE INHIBITOR drug used to treat breast cancer in menopausal women that has resisted anti-oestrogen drugs. Adjuvant treatment with letrozole in post-menopausal women with breast cancer appears to be more effective than tamoxifen in reducing the risk of recurrence. A brand name is Femara.
References in periodicals archive ?
NYSE: PFE) has released updated progression-free survival (PFS) results from the Phase 3 PALOMA-2 trial reinforcing the clinical benefit of Ibrance (palbociclib) combined with letrozole, the company said.
I am encouraged that women in Europe living with HR+/HER2- advanced breast cancer may be treated in first-line with ribociclib in combination with letrozole, which demonstrated strong progression-free survival of more than two years in the pivotal MONALEESA-2 trial.
The EU licence follows a positive opinion granted in June by the Committee for Medicinal Products for Human Use (CHMP) of the European Medicines Agency (EMA), which was based on the superior efficacy and an acceptable safety profile of Kisqali plus letrozole versus placebo plus letrozole in the pivotal Phase III MONALEESA-2 trial.
Letrozole works by decreasing how much estrogen the body makes, which could ultimately slow or stop the breast cancer from returning.
Eranni has reiterated several times that letrozole is not a performance-enhancing drug.
To date, only one study has investigated the optimal method of IUI timing in COH studies using a variety of COH medication protocols including CC, follicle-stimulating hormone (r-FSH), and letrozole (9).
Ribociclib 600 mg or placebo was administered orally once daily for 21 consecutive days, followed by 7 days off, with letrozole 2.
Of note, this study was funded in part by Novartis, the pharmaceutical manufacturer of letrozole, though the company had no role in either study design or writing of the manuscript.
Group B was given Letrozole at a dose of 1milligram/kilogram body weight.
SAN DIEGO -- The aromatase inhibitor letrozole didn't help boys with short stature grow taller, but it did boost their testosterone to concerning levels in a small study at Children's Hospital Los Angeles.