What is letrozole used for?

Letrozole belongs to a group called aromatase inhibitors. After menopause, much of the body’s oestrogen is made when aromatase changes other hormones into oestrogen. Blocking that process can deprive hormone-sensitive cancer cells of a growth signal.

A clinician may prescribe it after initial treatment, to reduce the chance of hormone-sensitive disease returning, or when cancer needs ongoing systemic treatment. The choice depends on tumour features, previous medicines, menopausal status and overall health. It is not a treatment for every cancer or every breast lump.

Take the prescribed tablet regularly and keep a record of symptoms. Do not stop, share or replace it without medical advice. Tell the oncology team about bone problems, liver disease, high cholesterol, pregnancy possibility and non-prescription products.

Hot flushes, reduced energy, joint stiffness, muscle aches and vaginal dryness are possible. The team can discuss movement, symptom relief, bone monitoring and alternatives when effects interfere with everyday life. Read more in Aromatase Inhibitor Drugs and Aromatase Inhibitor Therapy.

Report severe pain, a suspected fracture, unusual swelling, persistent weakness or symptoms that stop you taking the medicine. Get urgent help for sudden breathing difficulty, chest pain, or swelling of the lips, tongue or face.

Ask what feature of your cancer makes letrozole appropriate, how treatment will be monitored, how long it is expected to continue, and which side effects need a same-day call. Ask whether bone-health support or a different hormone medicine should be considered.