Aromasin (Exemestane) — Patient Information (UK)

Aromasin contains the active ingredient exemestane. It is an anti-cancer medicine used mainly in hormone receptor–positive breast cancer. This page explains how it works, how to take it safely, and what to expect. It is written for patients in the United Kingdom.

What is Aromasin?

Aromasin is a medicine that reduces the amount of oestrogen your body can make. In many breast cancers that are oestrogen-receptor positive, oestrogen can help cancer cells grow. By lowering oestrogen levels, Aromasin can help slow disease progression and reduce recurrence risk.

Aromasin belongs to a group of medicines called aromatase inhibitors. These medicines are commonly used in postmenopausal treatment strategies and may also be used in selected patients depending on clinical assessment.

How Aromasin works (mechanism of action)

Exemestane works by blocking the enzyme aromatase. Aromatase is responsible for producing oestrogen from androgen hormones (hormone “building blocks”) in tissues such as fat and muscle.

• Aromasin binds to and inactivates aromatase (an irreversible or “suicidal” inhibition style).
• This leads to a reduction in oestrogen production.
• For hormone receptor–positive breast cancer, lowering oestrogen may reduce cancer cell growth signals.

Importantly, Aromasin acts on oestrogen production. It does not directly replace or mimic oestrogen.

Pharmacokinetics (how your body processes it)

Pharmacokinetics describes how the medicine is absorbed, distributed, metabolised, and eliminated. Understanding these processes helps explain dosing and food advice.

• Absorption: Exemestane is absorbed from the stomach and intestines. Taking it with food can improve absorption.
• Peak levels: Exemestane reaches peak plasma concentrations after about 2 hours (typical range can vary between individuals).
• Metabolism: It is metabolised mainly in the body (predominantly in the liver), forming metabolites that are less active.
• Elimination: Exemestane and its metabolites are eliminated largely via urine and faeces.
• Steady effect: Because it permanently inactivates aromatase, its anti-oestrogen effect is sustained for aromatase activity, even though blood levels fluctuate over the day.

Your clinician may adjust treatment decisions based on liver or kidney function and overall health, although exemestane is generally used without frequent dose changes for mild-to-moderate impairment.

What it is used for (indications)

Aromasin is used for breast cancer where tumour growth is driven by hormones. Common indications include:

• Adjuvant treatment (after initial therapy) for early-stage hormone receptor–positive breast cancer, often in postmenopausal patients to reduce recurrence.
• Extended adjuvant therapy after initial endocrine treatment, in suitable patients.
• Treatment of advanced (metastatic) breast cancer in postmenopausal patients, especially when disease has progressed after other hormonal treatments.

Suitability depends on tumour biology (oestrogen receptor/progesterone receptor status), previous treatments, and menopausal status. Your treatment plan will be individualised.

Typical dosing and timing

Aromasin is typically taken as a once-daily dose. The most common dose is: 25 mg by mouth once daily.

When to take it

• Take Aromasin at the same time each day to help you remember.
• Many patients find it easiest to take it after a meal or with the evening meal.

How to take tablets

• Swallow the tablet with water.
• Do not crush or chew unless your pharmacist has advised otherwise.
• Use a routine reminder system (calendar, phone alarm, pill organiser) to maintain consistency.

If you miss a dose, follow the general principles below:

• If you remember soon after the missed time, take it when you next can take it with food.
• If it is almost time for the next dose, skip the missed dose and take your next dose as usual.
• Do not take two doses at once to make up for a missed tablet.

If you are unsure what to do after missing a dose, ask your pharmacist or prescriber for advice.

Food interactions and what to eat with Aromasin

Food can affect how much exemestane is absorbed. For best results:

• Take Aromasin after food (for example, after breakfast or after dinner).
• Taking it with food is generally recommended because it improves absorption and helps maintain consistent treatment exposure.

There are no specific “forbidden” foods, but maintaining a balanced diet and adequate hydration can help manage side effects such as fatigue or appetite changes.

Alcohol and medicine interactions

Alcohol does not have a single universal interaction with exemestane for everyone, but drinking alcohol can increase the risk of side effects such as dizziness, tiredness, nausea, and may worsen sleep or hot flush symptoms in some people.

Alcohol

• If you choose to drink alcohol, do so moderately and monitor how you feel on treatment.
• Avoid heavy drinking, especially if you experience nausea, headaches, or fatigue.
• If you have liver problems or take other medicines that affect the liver, ask your pharmacist for specific advice.

Medicine interactions (important)

Exemestane is metabolised by enzymes in the liver (notably CYP3A4). Some medicines can increase or decrease exemestane levels, potentially affecting effectiveness or side effects.

Always tell your pharmacist or prescriber about all medicines you take, including over-the-counter products, herbal supplements, and vitamins. Examples that may be relevant include:

• Strong enzyme inducers (which may reduce exemestane levels): for example, some medicines used for epilepsy or certain tuberculosis treatments.
• Strong enzyme inhibitors (which may increase exemestane levels): some antifungals and certain antibiotics.
• Herbal supplements: St John’s wort may affect drug metabolism in many people.

Do not start or stop other treatments without checking first. Your pharmacist can help you verify interactions quickly.

Safety profile: common and serious side effects

Like all medicines, Aromasin can cause side effects. Not everyone will experience them. Side effects vary by patient and by dose.

Common side effects

• Hot flushes
• Fatigue or tiredness
• Joint pain (arthralgia)
• Headache
• Nausea
• Vaginal dryness and changes in sexual comfort
• Sweating
• Reduced sleep quality in some people

Bone and muscle considerations

Because aromatase inhibitors lower oestrogen, they can affect bone health over time. You may be advised to have bone density monitoring and/or take measures to protect bones.

• Risk of bone thinning (osteopenia/osteoporosis)
• Risk of fractures in longer-term use
• Possible muscle aches and joint stiffness

Less common but serious side effects (seek urgent advice)

Contact urgent medical services or seek immediate advice if you experience symptoms that could indicate a serious reaction. For example:

• Signs of severe allergic reaction: swelling of face/lips, difficulty breathing, or widespread rash.
• Unusual bleeding or severe persistent stomach pain.
• Severe symptoms of liver issues: yellowing of the skin/eyes, dark urine, or persistent severe nausea.
• Chest pain or severe shortness of breath (requires urgent assessment).

This is not a complete list of side effects. If you are worried about any symptom, speak to a healthcare professional.

Practical tips for using Aromasin

Build a routine

• Take your tablet at the same time each day.
• Link it to a daily habit (after breakfast or after dinner).
• Use a pill organiser to reduce missed doses.

Manage joint pain and stiffness

• Gentle movement or light exercise (such as walking) can help.
• Warm compresses or stretching may reduce stiffness.
• If pain is persistent, discuss options with your clinician—sometimes supportive treatments or dose timing adjustments are considered.

Bone health support

• Ask about bone density scans if relevant to your situation.
• Ensure adequate calcium and vitamin D intake (via diet and supplements if advised).
• Engage in weight-bearing exercise where safe.
• Avoid smoking and limit alcohol, as these can affect bone health.

Hot flushes

• Dress in layers and keep your environment cool when possible.
• Avoid triggers such as spicy foods, alcohol, and hot drinks if they worsen symptoms.
• If hot flushes are severe, ask your healthcare team about symptom management options.

Alternative options

Aromasin is one aromatase inhibitor. Depending on your cancer type, prior treatments, and menopausal status, other endocrine options may be considered. Examples include:

• Other aromatase inhibitors: e.g., anastrozole, letrozole
• Selective oestrogen receptor modulators (SERMs): e.g., tamoxifen
• Selective oestrogen receptor downregulators (SERDs) or other endocrine therapies: used in specific circumstances
• Ovarian suppression approaches for selected pre-/peri-menopausal patients (where appropriate)

The best alternative depends on prior treatment history, side effect profile, and individual risks. Your clinician can help compare options and tailor the plan.

UK market and legal context

In the UK, Aromasin (exemestane) is an authorised medicine and is used under established clinical practice. Medicines are distributed through regulated pharmaceutical supply chains to ensure quality, safety, and traceability.

Availability may depend on current stock levels and product pack sizes. When ordering online, ensure the pharmacy is operating lawfully and uses appropriate channels for supply. In the UK, medicines must be supplied in accordance with regulatory requirements.

For patients, the most important step is continuity of supply and correct storage: keep tablets in a cool, dry place, protected from moisture, and follow the instructions on the pack.

Recent guidance and treatment monitoring (UK)

Guidance for breast cancer treatment and endocrine therapy is updated periodically by UK clinical bodies and international evidence reviews. While the exact schedule can change over time, monitoring typically includes:

• Regular clinical review for symptom changes and side effects
• Bone health assessment (e.g., bone density testing) for long-term aromatase inhibitor use
• Lifestyle and supportive care for joint symptoms, fatigue, and cardiovascular risk management where relevant
• Ongoing assessment of treatment response for advanced disease

Your healthcare team may also recommend blood tests or scans depending on your individual treatment stage and symptoms. Always follow the plan set by your oncology team.

Delivery and availability (online pharmacy)

Aromasin availability can vary by supplier and pack size. When ordering online in the UK, you can generally expect:

• Standard delivery options (timings depend on location and courier service)
• Tracking where provided by the courier
• Secure packaging to protect tablets from damage
• Customer service support if your delivery is delayed

Storage is important after delivery: keep the product in its original container and follow the pack instructions. If you have concerns about temperature exposure during shipping, contact the pharmacy for advice.

Safety information: who should take extra care?

Aromasin may not be suitable for everyone. Discuss your medical history with your healthcare team, especially:

• Allergies to exemestane or any tablet ingredients
• Liver disease or significant impairment
• Bone disorders or a history of fractures
• Severe kidney problems (your team may consider monitoring and supportive care)
• Medicines and supplements you currently take

Pregnancy and breastfeeding: aromatase inhibitors are generally not used in pregnancy or breastfeeding because of the need for oestrogen-dependent processes. Use effective contraception where relevant to your situation and seek advice immediately if pregnancy is possible.

FAQ — Frequently asked questions

1) How long do I take Aromasin?

Treatment duration depends on your cancer stage and response. For early-stage breast cancer, endocrine therapy is often given for a prolonged period (commonly several years), but the exact length is individual. Your oncology team will advise what duration applies to you.

2) Should I take Aromasin with food?

Yes. Aromasin is generally recommended after food because taking it with food improves absorption. Choose a mealtime you can repeat consistently each day.

3) What should I do if I vomit after taking Aromasin?

If you vomit shortly after taking a dose, it may not have been fully absorbed. Because timing matters, contact your pharmacist for guidance on whether to take another tablet. In general, do not take an extra dose without advice.

4) Can I stop Aromasin if I feel unwell?

Don’t stop on your own. Many side effects are manageable, and stopping suddenly could affect treatment effectiveness. Speak to your clinician or pharmacist promptly if side effects occur so that they can help you manage them safely.

5) Does Aromasin cause weight gain?

Weight changes can occur for many reasons during cancer treatment (stress, reduced activity, changes in diet). Aromasin is not always directly associated with weight gain, but individual responses vary. If weight change is significant, discuss it with your healthcare team.

6) Will Aromasin affect my bones?

It can. By lowering oestrogen levels, Aromasin may reduce bone mineral density over time. Your care team may suggest bone density tests, lifestyle measures, and—when appropriate—additional treatments to protect bones.

7) Are there interactions with herbal products?

Some herbal products can interact with drug-metabolising enzymes. In particular, St John’s wort may affect medicine levels. Tell your pharmacist about any herbal supplements or alternative remedies you use.

8) Can I take pain relief medicines?

Many people use occasional pain relief. However, which options are appropriate depends on your medical history and other medicines. Ask your pharmacist about suitable pain relief, especially if you have stomach ulcers, kidney disease, or are on anticoagulants.

9) What monitoring might I need?

Monitoring may include symptom reviews, bone health assessments, and other investigations tailored to your situation. For advanced disease, additional monitoring for treatment response may be required.

10) Who should contact me if there’s a problem with my treatment?

Your pharmacist and oncology team are best placed to advise. If you experience severe reactions or worrying symptoms, seek urgent medical help.

Important reminder

This information is designed to help you understand Aromasin and how it is commonly used. It does not replace advice from your healthcare team. If you have questions about your specific situation—such as dosing, side effects, interactions, or monitoring—speak to a pharmacist or prescriber.