I. Basic Drug Information

Generic Name: Anastrozole

Brand Name: Arimidex

Dosage Form & Strength: 1 mg/tablet; 28 tablets/box

Description: White film-coated tablets; appear white when the coating is removed.

Manufacturer: Eczacıbaşı Pharmaceuticals (Turkey)

Storage: Store at room temperature (20°C–25°C), protected from light and moisture.

II. Indications

Indicated for use in postmenopausal women for the following conditions:

1. Adjuvant treatment of early-stage breast cancer: Post-operative treatment for patients with hormone receptor-positive (HR+) disease, to reduce the risk of recurrence.

2. Treatment of advanced breast cancer:

First-line treatment: Locally advanced or metastatic HR+ or hormone receptor-unknown breast cancer.

Second-line treatment: Advanced breast cancer that has progressed following tamoxifen therapy.

3. Special populations: For estrogen receptor-negative (ER-) patients, use may be considered if they have demonstrated a positive response to tamoxifen.

III. Dosage and Administration

Standard Regimen

| Patient Population | Dosage and Administration | Duration of Treatment

| Postmenopausal Adults | 1 mg (1 tablet) once daily, orally | Adjuvant treatment: Continue for 5 years (optimal duration not yet established); Advanced disease treatment: Continue until tumor progression

| Patients with Hepatic/Renal Impairment | No dosage adjustment required for mild to moderate impairment; Contraindicated in severe impairment

Key Administration Notes

Administration Method: May be taken with or without food; swallow the tablet whole.

Missed Dose: Take the missed dose as soon as possible; if it is close to the time for the next scheduled dose, skip the missed dose and do not take a double dose.

Contraindicated Concomitant Use: Estrogen-containing medications (e.g., hormone replacement therapy, oral contraceptives) may reduce the efficacy of this drug. IV. Adverse Reactions

Common Adverse Reactions (Incidence ≥10%)

The table below summarizes the major adverse reactions and their frequencies, categorized by body system:

| Body System | Adverse Reactions | Incidence

| Systemic | Fatigue (19%), Hot flashes (35%), Pain (17%) | High

| Musculoskeletal | Arthralgia/Arthritis (36%), Bone pain (12%), Osteoporosis (11%) | High

| Nervous System | Headache (18%), Insomnia (10%), Depression (13%) | Moderate-High

| Gastrointestinal | Nausea (20%), Vomiting (11%), Diarrhea | Moderate

| Metabolic & CV | Hypertension (13%), Hypercholesterolemia (9%), Edema (10%) | Moderate

Serious Adverse Reactions

1. Skeletal Risks: Decreased bone mineral density → increased risk of fractures (10%).

2. Cardiovascular Events: Ischemic cardiac events (e.g., angina, myocardial infarction); the risk is particularly higher in patients with a history of coronary heart disease (17% in the Arimidex group vs. 10% in the Tamoxifen group).

3. Hepatic Dysfunction: Elevated transaminases, hepatitis (rare, but requires monitoring).

4. Allergic Reactions: Angioedema, urticaria, Stevens-Johnson syndrome (rare).

5. Thromboembolic Events: Deep vein thrombosis, pulmonary embolism (rare).

V. Contraindications

Contraindicated in the following populations:

1. Premenopausal women (no clinical benefit).

2. Pregnant and lactating women: Teratogenic risk (animal studies indicate pregnancy loss and fetal malformations).

3. Severe hepatic or renal impairment:

- Hepatic impairment: Moderate to severe (Child-Pugh Class B-C);

- Renal impairment: Creatinine clearance <20 mL/min.

4. History of Hypersensitivity: Patients with known hypersensitivity to anastrozole or to any of the excipients (including lactose). VI. Precautions

1. Bone Health Management:

- Monitor bone mineral density (e.g., via DEXA scans) prior to treatment and at regular intervals; co-administer bisphosphonates to prevent bone loss if necessary.

2. Cardiovascular Monitoring:

- Use with caution in patients with a history of coronary heart disease; seek immediate medical attention if chest pain or dyspnea occurs.

3. Liver Function and Lipids:

- Periodically monitor levels of transaminases, alkaline phosphatase, and cholesterol.

4. Special Populations:

- Patients with Lactose Intolerance: The excipients contain lactose, which may trigger diarrhea or abdominal bloating.

- Athletes: May affect athletic performance; use with caution.

VII. Use in Specific Populations

Children: Safety has not been established; contraindicated.

Elderly: No dose adjustment required; however, intensified monitoring of bone mineral density and cardiovascular status is recommended.

Hepatic/Renal Impairment: No dose adjustment required for mild to moderate impairment; contraindicated in cases of severe impairment.

VIII. Pharmacological Mechanisms and Pharmacokinetics

Mechanism of Action: A potent, selective aromatase inhibitor that blocks the conversion of androgens into estrogens, thereby reducing plasma estradiol levels by >80%.

Pharmacokinetics:

- Rapid oral absorption, with peak plasma concentrations reached in approximately 2 hours.

- Plasma elimination half-life of 40–50 hours; steady-state concentrations are achieved within 7 days.

- Metabolized primarily in the liver; excreted via the kidneys (<10% as unchanged drug).

X. Overdosage and Management

Symptoms: No specific signs of toxicity have been identified to date.

Management: Induction of emesis or hemodialysis (given the low plasma protein binding rate).

Summary: Arimidex is a cornerstone therapy for postmenopausal patients with hormone receptor-positive (HR+) breast cancer. Particular attention must be paid to bone safety, cardiovascular risks, and liver function monitoring, while strictly avoiding use in the presence of contraindications. Specific dosing and administration should strictly adhere to physician's orders.

Note: The information provided above is a summary compilation and does not constitute a substitute for a medical prescription. Please consult your attending physician prior to use and undergo regular follow-up examinations to assess efficacy and safety. **Product Specifications**

**Product Name:** Arimidex Anastrozole Tablets 1mg × 28 Tablets/Box

**Common Name:** Arimidex

**Active Ingredient:** Anastrozole

**Dosage Form:** Tablets

**Specification:** 1mg/tablet; 28 tablets/box

**Manufacturer:** Eczacıbaşı Pharmaceuticals (Turkey)

**Indications:** Indicated for postmenopausal women in the following situations:

1. **Adjuvant Treatment for Early Breast Cancer:** Post-operative treatment for patients with hormone receptor-positive (HR+) early breast cancer to reduce the risk of recurrence.

2. **Treatment of Advanced Breast Cancer:**

**First-line treatment:** For locally advanced or metastatic HR+ (or hormone receptor-unknown) breast cancer.

**Second-line treatment:** For advanced breast cancer that has progressed following tamoxifen therapy.

3. **Special Populations:** For estrogen receptor-negative (ER-) patients, use may be considered if they have shown a positive response to tamoxifen.

**Dosage and Administration:**

1. **Advanced Breast Cancer in Postmenopausal Women**

**Oral Dosage:** 1 mg (1 tablet) once daily. May be taken with or without food; it is recommended to take the medication at a fixed time each day.

**Duration of Treatment:** Continue treatment until disease progression occurs or until intolerable adverse reactions develop.

2. **Adjuvant Treatment for Early Breast Cancer in Postmenopausal Women**

**Oral Dosage:** 1 mg once daily. The recommended duration of treatment is 5 years.

**Target Population:** Patients with hormone receptor-positive (ER/PR+) early breast cancer; post-operative adjuvant treatment helps reduce the risk of recurrence.