Anastrozole

Sounds like 'an-as-tro-zole'

Easy-to-read medicine information about anastrozole – what it is, how to take anastrozole safely and possible side effects.

Type of medicine Also called
  • Belongs to a group of medicines known as aromatase inhibitors
  • Rolin®
  • Arimidex®
  • DP-Anastrozole®
  • Aremed®

What is anastrozole?

Anastrozole is used to treat some types of breast cancer in women who have gone through menopause. This type of breast cancer is called oestrogen receptor-positive (ER-positive) breast cancer. Anastrozole is a type of medicine called an aromatase inhibitor. It blocks (inhibits) the activity of aromatase and reduces the amount of oestrogen in the body, and in this way it slows or stops the growth of the cancer cells. In New Zealand anastrozole is available as tablets. 

Dose

  • The usual dose of anastrozole is 1 tablet (1 milligram) once a day.
  • Anastrozole is a long-term treatment; you may have to take it for several years.
  • Always take your anastrozole exactly as your doctor has told you. The pharmacy label on your medicine will tell you how much to take, how often to take it, and any special instructions.

How to take anastrozole

  • Take anastrozole at the same time each day, either in the morning or the evening. 
  • You can take anastrozole with or without food.
  • It is not harmful if you miss a dose of anastrozole. If you forget to take your dose, take it as soon as you remember. But, if it is nearly time for your next dose, just take the next dose at the right time. Do not take double the dose.
  • Do not stop taking anastrozole suddenly; speak to your doctor before stopping.

Precautions – before starting anastrozole

  • Are you still having menstrual periods? If you have not gone through the menopause you should not take anastrozole
  • Do you have osteoporosis (a condition that causes your bones to be thinner and weaker than normal)?
  • Do you have problems with your liver or kidneys?
  • Are you taking any other medicines, including medicines you can buy without a prescription, such as herbal and complementary medicines?

If any of these apply, it’s important that you tell your doctor or pharmacist before you start anastrozole. Sometimes a medicine isn’t suitable for a person with certain conditions, or it can only be used with extra care.

Possible side effects

Like all medicines, anastrozole can cause side effects, although not everyone gets them. Often side effects improve as your body gets used to the new medicine.

Hot flushes and sweats

These are common and are often mild, but this can vary. Hot flushes and sweats may improve after the first few months. You can try to reduce hot flushes and sweats by not smoking, reducing alcohol and avoiding hot drinks containing caffeine, such as tea and coffee.Try to dress in layers, so you can remove clothes as needed, and wear clothes made from natural fabrics, such as cotton. If hot flushes are troubling you, tell your doctor or nurse. There are some medicines that can help to reduce flushes.

Other side effects

Side effects What should I do?
  • Stomach upset, nausea (feeling sick), or vomiting
  • Try taking anastrozole with food or just before bed
  • Tell your doctor if troublesome. 
  • Feeling tired, lack of energy
  • Sleep problems
  • Aching or pain in the joints or muscles
  • Vaginal dryness
  • Headache
  • These may improve with time
  • Tell your doctor if troublesome
  • Do not drive if drowsy
  • Skin rashes, itching, swelling of the face, lips or mouth.
  • Vaginal bleeding
  • Tell your doctor immediately or ring HealthLine 0800 611 116

Interactions

Anastrozole can interact with a few medicines and herbal supplements, so check with your doctor or pharmacist before starting anastrozole or before starting any new medicines or supplements.

Learn more

Arimidex Medsafe Consumer Information

References

  1. anastrozole New Zealand Formulary
  2. Breast cancer New Zealand Formulary
Credits: Sandra Ponen, Pharmacist. Reviewed By: Angela Lambie, Pharmacist, Auckland Last reviewed: 12 Jan 2018