Letrozole is the active ingredient of Femara tablets (Nappi code:
Letrozole is an antineoplastic. Antineoplastics are drugs that prevent the
development or growth of cancer cells.
In South Africa letrozole is registered for the treatment of early and
advanced breast cancer in postmenopausal woman. It has not proved effective in
cancers that are not oestrogen-sensitive.
For this medication to be effective, it has to be taken regularly, even if
you do not notice an immediate effect.
Be careful if you drive or do anything that requires you to be alert. Avoid
any other dangerous activity until you know how this medication affects you.
How does letrozole work?
Letrozole inhibits an enzyme, which is partially responsible for the
production of natural oestrogens in the body. As a result oestrogen production
is reduced by as much as 90%. By lowering oestrogen levels in the body,
letrozole effectively "starves" the breast cancer cells, thereby inhibiting
Drug schedule: schedule 4
Available as: letrozole is available as tablets
What does it do? Letrozole slows the progression of breast cancers,
most of which are stimulated by oestrogens.
Overdose risk: low
Dependence risk: low
Is letrozole available as a generic? no
Is letrozole available on prescription only? yes
Stopping this medicine: do not stop taking this drug without
consulting your doctor.
Consult your doctor before using this drug if:
- you have osteoporosis
- you have any doubt as to whether or not your menopause has
- you have kidney or liver disease
Pregnancy: avoid. Potential risk to the foetus has been reported.
Consult your doctor before use, or if you are planning to fall pregnant.
Breastfeeding: avoid. This medication is passed through breastmilk and
may affect your baby adversely. Consult your doctor before use.
Porphyria: avoid. It is unknown how this medication may affect your
condition. Consult your doctor before use.
Infants and children: this medication is not intended for use in
The elderly: no special precautions need to be taken.
Driving and hazardous work: caution is advised as use of this
medication may lead to dizziness, light-headedness and/or sedation. Avoid such
activities until you know how this medication affects you.
Possible side effects
| Side effect
|| Consult your doctor
||Only if severe
||In all cases|
|| Oppose the effect of letrozole |
A small overdose is no cause for concern. In case of
intentional large overdose, seek emergency medical
Adults, oral: 2.5mg once
Although not indicated, it has been used for
ovulation induction by fertility doctors; it has fewer side effects than
clomiphene citrate (Clomid) for the patient and may lower the risk of multiple
This material is not intended to substitute medical advice, but is for
informational purposes only.
Please consult a physician for specific treatment and