anastrozole at a glance
Medicine class
Non-steroidal aromatase inhibitor
Main role
Treatment of hormone receptor-positive breast cancer after the menopause
Administration
Swallow the tablet whole with water, with or without food
Important long-term issue
Reduced bone mineral density and increased fracture risk
What is anastrozole used for?
The selected UK product is licensed after the menopause for:
Hormone receptor-positive advanced breast cancer.
Additional treatment for hormone receptor-positive early invasive breast cancer, including after previous tamoxifen treatment.
Primary prevention of breast cancer in women assessed as being at moderate or high risk.
How does anastrozole work?
After the menopause, much of the body's oestrogen is made when the aromatase enzyme converts other hormones into oestrogen. Anastrozole selectively inhibits aromatase, reducing oestrogen that can stimulate hormone-sensitive breast cancer cells.
anastrozole preparations and strengths
Tablet
Route: Oral
Strengths: 1 mg
How to take anastrozole
Follow the directions on the dispensing label and from the specialist team.
Swallow the film-coated tablet whole with water; do not crush or chew it.
It may be taken with or without food.
Do not stop or pause treatment without discussing this with the specialist team.
Do not drive or use machinery if it causes tiredness, weakness or dizziness.
anastrozole side effects
Common or expected effects
- Hot flushes
- Joint pain or stiffness and arthritis
- Headache
- Tiredness or weakness
- Nausea, vomiting or diarrhoea
- Low mood
- Rash or hair thinning
- Vaginal dryness or bleeding
- Reduced bone density or osteoporosis
- Raised cholesterol
Get urgent medical advice
- Severe allergic reaction or angioedema
- Severe blistering or peeling skin reaction
- Liver inflammation, including jaundice
- Inflammation of blood vessels, sometimes with a purple or dark-spotted rash
- High blood calcium with marked thirst, frequent urination or nausea
- Tendon inflammation or rupture
- Possible heart attack or stroke symptoms
anastrozole in pregnancy
Anastrozole is contraindicated during pregnancy. Anyone who may be pregnant, whose periods restart, or who is planning pregnancy should contact their prescriber promptly and discuss reliable contraception where relevant.
anastrozole while breastfeeding
Anastrozole is contraindicated while breastfeeding. There are no adequate human lactation data, and its hormonal effects could affect a breastfed child; discuss alternatives with the specialist team.
anastrozole interactions
Check all prescribed, non-prescribed and complementary products with a pharmacist or prescriber.
Tamoxifen
Avoid concurrent use because it may reduce anastrozole's pharmacological effect.
Oestrogen-containing treatments, including HRT
They may oppose anastrozole's oestrogen-lowering action and should generally be avoided.
Herbal or complementary products for menopausal symptoms
Safety and interaction evidence is limited, and some products may interfere with treatment.
Common questions about anastrozole
Answers are fully visible for fast scanning and source review.
Is anastrozole chemotherapy?
No. It is endocrine therapy that lowers oestrogen by inhibiting aromatase.
Can anastrozole be taken with food?
Yes. It can be taken with or without food and swallowed whole with water.
Can anastrozole weaken bones?
Sources
These sources were used to prepare and review this medicine page.
Prepared and reviewed by the iatroX editorial team.