Anazole

Quick links to important sections

Anazole

Treatment option:

Medically reviewed

Laura Arias

Last updated on 22/12/2025

This page provides general, reference-level information compiled from official medical sources. It is not a substitute for professional medical advice, diagnosis, or treatment. For decisions about your health, please consult a qualified healthcare professional.

Overview of Anazole

Property Description
Active ingredient Anastrozole (C17H19N5)
Form Film-coated tablets (oral administration)
Pharmacological class Non-steroidal aromatase inhibitor (AI)
Common use Reduction of circulating estrogen levels in hormone-sensitive contexts
Origin Synthetic compound (azole derivative)

Anazole: Identity and Pharmacological Classification

Anazole is the trade designation for the active ingredient Anastrozole, a highly selective, synthetic compound officially classified as a Non-steroidal aromatase inhibitor (AI). The drug is formally grouped with Antineoplastic and immunomodulating agents, reflecting its function as a targeted endocrine therapy. As a single-agent product, Anazole is consistently supplied as film-coated tablets for oral administration, utilizing excipients such as lactose monohydrate to form a stable solid dosage. This medicine works by suppressing the action of an enzyme crucial for hormone production in the body. This targeted mechanism is widely clinically recognized for its specific application in reducing systemic estrogen exposure, particularly in postmenopausal women, which distinguishes its use from premenopausal hormonal therapies.

How Does Anazole Fundamentally Function?

Anazole fundamentally functions as an anti-estrogen agent by causing the potent and selective, yet reversible, inhibition of the aromatase enzyme. This enzyme is crucial for estrogen biosynthesis—catalyzing the conversion of androgens into the potent hormone estradiol—primarily within peripheral tissues like fat and muscle. By achieving effective peripheral tissue conversion blockade, Anastrozole significantly reduces the body's concentration of circulating estrogen. The primary role of Anastrozole is a mechanism that decreases the amount of estrogen the body makes by inhibiting the aromatase enzyme. This ability to suppress estrogen production is the underlying goal of the suppression therapy, offering a recognized therapeutic strategy in hormone-sensitive contexts.

Regulatory References

  1. Aromatase Inhibitors - NCBI Bookshelf (NIH)

What side effects are possible with Anazole?

Possible Side Effects and Safety Information

Regulatory safety documents define the adverse reaction profile of Anazole (Anastrozole) through classification by frequency and affected organ system. This information is strictly based on data from governmental health authorities. The profile establishes known risks and defines specific constraints for its use.

Frequency-Classified Adverse Reactions

The most frequently documented effects, classified as Very Common (occurring in 1 in 10 or more people), include hot flushes, asthenia (weakness/fatigue), arthralgia (joint pain), joint stiffness, headache, nausea, and rash. Effects classified as Common include bone pain, vomiting, diarrhea, hair thinning (alopecia), and hypercholesterolaemia (elevated cholesterol levels). Uncommon reactions include hepatitis, urticaria, and hypercalcaemia.

Serious Adverse Reactions and Safety Constraints

The official label highlights specific serious or clinically significant safety considerations. Anazole can cause a reduction in Bone Mineral Density (BMD), leading to an increased risk of osteoporosis and fractures. Rarely, severe cutaneous reactions such as Stevens-Johnson Syndrome and Angioedema have been documented. The use of Anazole is strictly contraindicated in premenopausal women, and its safety profile requires caution in patients with severe renal or hepatic impairment. Due to reports of somnolence and asthenia, patients are advised to observe caution when driving or operating machinery if these symptoms occur.

Time-related patterns note that vaginal bleeding is primarily reported during the initial weeks after changing from prior hormonal therapy. Co-administration with oestrogen-containing therapies or Tamoxifen is to be avoided, as this may counteract its intended safety profile.

Overdose and Emergency Response

Anazole Overdose and when to seek help

The official regulatory documents for Anazole (Anastrozole) state that clinical experience with accidental overdosage is limited, and there is no specific dose-limiting toxicity defined in the labeling. The documented profile indicates that overdose manifestations are expected to be an exaggeration of known adverse effects of the medicine. No single dose resulting in life-threatening symptoms has been established.

In the event of a suspected overdose, immediate medical attention must be sought. Emergency services should be called immediately if the individual has collapsed, experienced a seizure, or has trouble breathing.

Management is strictly symptomatic and supportive because no specific antidote is known. Regulatory guidance mandates that treatment includes close observation of the patient, with frequent monitoring of vital signs. Supportive procedures, such as administering activated charcoal or inducing emesis (vomiting), may be considered if ingestion was recent and the patient is conscious. No specific dose adjustments are required for elderly patients or those with mild-to-moderate renal or hepatic impairment, though the medicine has not been studied in cases of severe impairment.

Therapeutic Uses of Anazole

Quick Facts: Therapeutic Domains

  • Management of early hormone receptor-positive breast cancer in postmenopausal women.
  • Initial treatment option for locally advanced or metastatic hormone receptor-positive breast cancer in postmenopausal women.
  • Care for advanced breast cancer following disease progression after prior treatments.

What Anazole treats: main uses and benefits

Anazole (generic name: anastrozole) is a treatment option indicated for managing specific forms of breast cancer in women who have completed menopause. Its primary purpose is to address cancers that rely on hormones for growth, referred to as hormone receptor-positive disease.

This medication is used in the adjuvant setting, which means it is administered following primary treatments such as surgery, for managing early hormone receptor-positive breast cancer. It is also an initial therapeutic choice for postmenopausal women who present with locally advanced or metastatic disease, where the hormone receptor status is positive or unknown.

Furthermore, Anazole may be used to address cases of advanced breast cancer in postmenopausal women where the condition has progressed after prior treatment with certain anti-estrogen therapies. This use provides a continuing avenue for managing the disease course.

Eligibility and Restrictions for Use

Official Population Eligibility for Anazole

Anazole is exclusively approved and established for use in postmenopausal women (adults, including the elderly). Regulatory documents define strict population-based exclusions and restrictions for its use.

Contraindicated and Non-Eligible Groups

Anazole is contraindicated in several populations. These absolute exclusions include pregnant women and lactating women, as well as all women of premenopausal endocrine status. The medicine must also not be used by patients with a known hypersensitivity to the active ingredient or who have specific hereditary metabolic disorders, such as galactose intolerance.

Conditional Use and Restrictions

Use in certain populations requires specific caution or monitoring as outlined in the official labeling:

  • Organ Function: Caution is advised for patients diagnosed with severe renal impairment or moderate to severe hepatic impairment.
  • Comorbidity: Women with or at risk of osteoporosis are required to undergo Bone Mineral Density (BMD) assessment and monitoring.
  • Pediatric Status: Use is not recommended for children and adolescents, as safety and efficacy have not been established in this age group. Co-administration with Tamoxifen or estrogen-containing therapies is also advised against.

What should I know about interactions with other medicines?

Interactions with other medicines and products

Official regulatory documentation identifies specific patterns of interaction for Anazole (Anastrozole) with other medicinal products and certain conditions.


Documented Interaction Restrictions

Co-administration of Anazole with Tamoxifen is officially not recommended, as this combination has been shown to reduce the plasma concentration of Anazole by approximately 27%. The use of estrogen-containing medicinal products, including hormone replacement therapy, is prohibited due to the risk of pharmacodynamic antagonism, which directly counteracts the estrogen-suppressing action of Anazole. These combinations are considered contraindicated.


Pharmacokinetic and Substance Interactions

Substance Official Interaction Outcome
Warfarin Co-administration may result in an increase in Prothrombin Time (PT) and International Normalized Ratio (INR), requiring monitoring.
Food Food reduces the rate of Anazole absorption (delayed Tmax and decreased Cmax), but the overall extent of absorption (AUC) remains unaffected.
CYP Enzymes Anazole is officially documented as unlikely to cause clinically significant inhibition of Cytochrome P450 enzyme-mediated metabolism for co-administered drugs.

Population-Specific Considerations

The apparent oral clearance of Anazole is approximately 30% lower in subjects with stable hepatic cirrhosis compared to healthy controls. This observation in individuals with mild-to-moderate hepatic impairment reflects an altered pharmacokinetic profile, but the regulatory labels do not require a dosage adjustment based on this information.

Mechanism of Action

Anazole (Anastrozole) acts via selective competitive inhibition with a key enzyme responsible for steroid hormone production, resulting in a systemic physiological change.

Targeted Enzyme Inhibition: Aromatase Blockade

Anazole works as a selective, non-steroidal competitive inhibitor of the Aromatase enzyme (CYP19A1). This enzyme catalyzes the final biochemical conversion of androgen precursors (like androstenedione) into active estrogens (like estradiol). By reversibly binding to the enzyme's active site, the drug directly blocks the catalytic activity of the enzyme, halting this conversion process.

Pathway Modulation: Peripheral Estrogen Synthesis

This molecular blockade initiates a mechanistic cascade that inhibits the synthesis of estrogen in certain physiological states. The drug's action primarily occurs in peripheral tissues (such as adipose tissue and muscle) where aromatase activity is present. The resultant suppression of local estrogen synthesis leads to a substantial reduction in the concentration of circulating estradiol (E2) throughout the body.

Induction of Systemic Hypoestrogenism

The combined and sustained effect of the inhibition mechanism is the controlled induction of a state known as systemic hypoestrogenism. This physiological outcome causes a significant withdrawal of the primary estrogenic stimulus, thereby reducing the overall signaling load on estrogen receptors across various bodily systems.

Dosage and Administration Information

How to Use Anazole: Official Administration Guidelines

This section outlines the official administration instructions for Anazole (Anastrozole). These guidelines define the standardized protocol for its use, ensuring consistency across approved indications.


Administration Scope

Property Instruction
Route of Administration Oral (taken by mouth).
Standard Dosing Schedule 1 mg once daily.
Timing in Relation to Meals May be taken with or without food.
Preparation Requirements None; the film-coated tablet should be swallowed whole.
Population-Specific Rules Geriatric Patients: No dose adjustment is required. Hepatic/Renal Impairment (Mild to Moderate): No dose adjustment is generally required.
Missed-Dose Rule If a dose is missed, take the next dose at the regular scheduled time; a double dose should not be taken to compensate.

Treatment Course and Schedule

Property Classification
Administration Method Type Oral
Frequency Pattern Daily
Use-Context Constraint (Duration) Adjuvant Setting: The typical duration is often five years. Advanced Disease: Treatment continues until there is objective disease progression.

Resulting Procedural Structure

The required procedural structure for administration is straightforward. The 1 mg tablet must be taken once per day at approximately the same time, without regard to meal timing. This fixed, daily dose is the standard regimen for all approved uses and does not typically require adjustment in common patient subgroups.

Recent Clinical Evidence

Research Evidence / Overview of Studies for Anazole

Evidence for Adjuvant Treatment of Early Breast Cancer

Research exploring Anazole in the context of primary treatment for early breast cancer (known as adjuvant treatment) has been widely studied in large, international Randomized Controlled Trials (RCTs). These studies primarily included postmenopausal women diagnosed with hormone receptor-positive early-stage breast cancer. Researchers monitored outcomes related to the disease recurring, specifically measuring the time researchers tracked without the disease recurring (Disease-Free Survival or DFS).

Patterns related to these measurements were reported to continue into the long-term follow-up periods. However, initial trial reports described that overall survival measurements were not statistically different between the studied treatments. Long-term observation continues to track measurements of overall survival in these patient cohorts. The data for certain small subgroups of patients, such as those with very low baseline hormone receptor expression, remain insufficient.


Evidence for Treatment of Advanced or Metastatic Breast Cancer

Research explored Anazole in the advanced disease context as both an initial focus of study (first-line focus) and as a subsequent focus of study (second-line focus). This research primarily involved postmenopausal women in Randomized Controlled Trials. Research focused on short-to-intermediate outcomes, measuring the tumor's response (Objective Response Rate or ORR) and the duration before the disease was documented to progress (Time to Progression or TTP).

In the first-line setting, some large trials data show patterns related to measurements of ORR and TTP that were similar to those observed with the comparator treatment. When evaluated in the second-line setting, studies comparing Anazole to other hormonal agents reported measurements of TTP and overall survival that were generally similar across the studied groups. Evidence for the second-line setting is limited as trials were often structured to explore non-inferiority to the standard.

Key Studies & References

  1. Long-term follow-up of the ATAC (Arimidex, Tamoxifen Alone or in Combination) trial: 10-year analysis of recurrence and survival

Frequently Asked Questions (FAQ)

Common questions about Anazole (FAQ)


Q: What is the main condition Anazole is approved to treat?

Official regulatory documents state that Anazole is indicated for the treatment of hormone receptor-positive early invasive breast cancer and advanced or metastatic breast cancer. Its established use is specific to postmenopausal women.


Q: Is Anazole used to treat conditions other than its main approved use?

Regulatory documents explicitly list the specific approved conditions for Anazole. Use outside of these specific, approved indications is often referred to as unapproved or off-label use.


Q: How quickly does Anazole typically begin to work?

Anastrozole is rapidly absorbed after administration, with the maximum amount in the blood typically reached in about one hour. The drug’s documented mechanism of estrogen suppression is described as beginning rapidly after administration.


Q: How long after starting Anazole should I expect to see its full effect?

Achieving a consistent level of the drug in the body, known as steady-state concentration, typically occurs after about seven days of consistent daily dosing. The pharmacokinetic data suggests this timeframe is when the maximum level of estrogen suppression is generally achieved.


Q: Is Anazole the same type of medicine as other similar sounding treatments?

Anazole is formally classified as a non-steroidal aromatase inhibitor. This is a specific type of medicine used for its intended purpose. Other treatments for the same condition may also belong to this pharmacological class, but they contain distinct active ingredients.


Q: What is the key difference between Anazole and other medications for the same condition?

Anazole (Anastrozole) is classified as a non-steroidal aromatase inhibitor. This mechanical classification distinguishes its mechanism from other types of hormonal treatments, such as steroidal aromatase inhibitors or Selective Estrogen Receptor Modulators (SERMs).


Q: Does Anazole cause changes in weight (gain or loss)?

Official clinical trial data indicate that weight gain is listed as a common adverse reaction for Anazole. However, some data suggest that Anazole treatment avoids the specific weight gain profile associated with certain older competitor treatments.


Q: Is it safe to use Anazole if I am taking over-the-counter pain relievers?

Official product labels require patients to inform their prescribing doctor about all medications, including over-the-counter (OTC) products. The official documentation emphasizes the need for full disclosure since some common medications may have ingredients that could potentially interact with Anazole.


Q: Does Anazole interact with common vitamins or herbal supplements?

Official information notes that Anazole may interact with certain supplements, such as DHEA, which is listed in some regulatory documents. The official patient information advises disclosing all herbal products and supplements being taken to a healthcare provider.


Q: Are there any specific foods or drinks I should avoid while on Anazole?

Official food interaction notes describe that while food slows the rate of Anazole absorption, it does not change the total amount absorbed. Some patient guides mention that avoiding potential triggers like alcohol may help in managing common side effects, such as hot flashes.


Q: Can men use Anazole, or is it only for women?

Official regulatory documents clearly specify that Anazole is indicated only for postmenopausal women. The safety and efficacy data from clinical trials were established specifically in this patient population.


Q: Why do doctors prescribe Anazole instead of other treatment options?

Clinical trial data show patterns related to favorable effectiveness in measures like Disease-Free Survival (DFS) when compared to older hormonal therapies. Anazole's non-steroidal aromatase inhibitor mechanism is generally accepted as a primary treatment strategy in hormone-sensitive contexts.


Q: Is there a generic version of Anazole available?

Yes, Anastrozole is the active ingredient and the official generic name for Anazole. A generic version of this medicine is available from various pharmaceutical manufacturers.


Q: Will Anazole change the effectiveness of birth control pills?

Anazole is strictly contraindicated for use with any medicine that contains estrogen, which includes most hormonal birth control pills. This combination is avoided because of the potential for the estrogen-containing product to counteract the intended anti-estrogen action of Anazole.


Q: Is Anazole known to cause mood changes or depression?

Official clinical trial data list mood disturbances as a common adverse reaction reported by some patients. This information is included in the official Summary of Product Characteristics (SmPC) and similar regulatory documents.


Q: Are there any ongoing clinical trials for Anazole I should be aware of?

Regulatory documents, such as the official prescribing label, focus on evidence for approved uses. Information concerning ongoing or future clinical trials is typically managed by the study sponsors and is not detailed in the standard drug label.


Q: Is it safe to drink alcohol in moderation while taking Anazole?

While no definitive negative interaction is listed in the core documents, patient information suggests that alcohol may act as a potential trigger. This is mentioned because alcohol consumption may worsen common side effects like hot flashes.


Q: Why do some people report feeling lightheaded when starting Anazole?

Dizziness and somnolence (a term for drowsiness or sleepiness) are listed as common side effects in the official product information. These known effects may be why some people report feeling lightheaded when beginning treatment.


Q: Does Anazole interact with common cold or flu medications?

The official product information requires patients to inform their healthcare team about all medications, including over-the-counter cold and flu products. The disclosure requirement is in place because some common cold and flu ingredients may potentially interact with Anazole.


Q: How long does Anazole stay in the body after the last dose?

Pharmacokinetic data from the official label indicate that the terminal elimination half-life of Anastrozole is approximately 46.8 hours. This measurement helps describe how long the medicine's active concentration remains in the body after the final dose.


Q: Does Anazole require a special prescription from a specialist?

Anazole is classified as a prescription-only medicine (POM) and is generally prescribed in a specialized oncology setting. While the label does not restrict who can write the prescription, its context often involves coordination with a specialist.


Q: What does 'contraindication' mean in relation to Anazole?

A contraindication means that the medicine must not be used in a particular situation, such as in a specific patient group or alongside certain other medications. This rule is in place because the potential risks are significantly higher than the benefits in those situations.


Q: Are there any official documents or guides about Anazole for patients?

Official regulatory documents mandate that the drug be supplied with a Patient Information Leaflet (PIL) or similar comprehensive patient guide. This document provides important details about the drug's use, potential side effects, and safety.


Q: Is Anazole considered a high-risk medication by regulatory bodies?

Regulatory bodies classify Anazole as a prescription-only antineoplastic agent used to treat cancer. While it comes with specific warnings about serious risks, such as bone mineral density loss, official documentation does not use a general 'high-risk' classification.

How should Anazole be stored and disposed of?

How to Store and Dispose of Anazole (Anastrozole) Tablets

Official regulatory documents stipulate specific conditions for the storage and handling of Anastrozole tablets to ensure product integrity.


Storage Requirements

Condition Requirement
Temperature Store at controlled room temperature, typically 20 C to 25 C (68 F to 77 F).
Protection Keep the tablets protected from moisture and do not expose them to extreme temperatures.
Container The medication must be kept in its original container.
Child Safety It is mandatory to keep the medicine out of the sight and reach of children.

Disposal Instructions

Unused or expired Anastrozole must not be thrown away via wastewater or standard household trash. Disposal must be performed according to local regulations or determined by a qualified pharmacist.

Attention! Always consult to a doctor or pharmacist before using pills or medicines.

Equivalent of Anazole found in:

A-Z Index: