Femistra (Anastrozole 1mg) Tablets

Femistra general information

What is Femistra used for?

Femistra tablets 1mg are used to treat breast cancer that has been identified as hormone receptor positive for oestrogen, in postmenopausal women, at various stages of tumour development.  These include treatment of early breast cancer to reduce the risk of the cancer returning or spreading to the other breast; adjuvant (additional) treatment for early breast cancer, in conjunction with tamoxifen, which is a targeted therapy for breast cancer, in women who have received 2 to 3 years of tamoxifen therapy or if tamoxifen therapy has not helped prevent progression of the tumour.  Adjuvant treatment is hormone therapy in addition to other forms of cancer treatment such as radiation, cytotoxic (chemo), biological or targeted therapy.  Femistra tablets 1mg are used as first line therapy for advanced or metastatic breast cancer, which is when the tumour has spread out of the breast tissue to the lymph nodes or other tissues like the bones, lung and liver.  Femistra tablets 1mg are only effective in breast cancers that are positive for oestrogen receptors, which is the most common form of breast cancer and are dependent on oestrogen for tumour growth. 

How does Femistra work?

Femistra tablets 1mg contain anastrozole, which is a potent and highly selective inhibitor of aromatase, an enzyme that is involved in the biosynthesis of the female hormone oestrogen.  In premenopausal women the primary source of oestrogen production are the ovaries and oestrogen is involved in producing secondary sexual characteristics, such as breast development and in regulating the menstrual cycle.  In postmenopausal women, when oestrogen production by the ovaries ceases, low levels of oestrogen are made in peripheral tissues, such as fat cells throughout the body, also some breast cancer cells, by conversion of androstenedione (produced by the adrenal glands) to estrone, due to the action of aromatase and then by further conversion to oestradiol (the most active form of circulating oestrogen).  Many breast cancers have oestrogen receptors and their growth is stimulated by oestrogen; low levels of oestrogen may be sufficient to maintain growth of breast cancer cells in women with breast cancer.  Anastrozole in Femistra tablets 1mg blocks the action of aromatase, preventing the formation of oestrogen and helping to prevent growth of oestrogen-dependent breast tumours. 

What does Femistra contain?

Femistra tablets 1mg contains the active ingredient anastrozole 1mg, an aromatase inhibitor that blocks oestrogen biosynthesis and is used to treat breast cancer.  They also contain lactose monohydrate, magnesium stearate, opadry white Y-1-7000, povidone, purified water and sodium starch glycolate.

Treating breast cancer with Femistra

Femistra tablets 2.5mg contain anastrozole, which is a potent and highly selective aromatase inhibitor that is used to treat oestrogen receptor positive breast cancers at various stages of tumour development in postmenopausal women.  Many breast cancers have oestrogen receptors and their growth is stimulated by oestrogen; low levels of oestrogen may be sufficient to maintain growth of breast cancer cells in women with breast cancer.  Anastrozole in Femistra tablets 1mg blocks the action of aromatase, an enzyme involved in the biosynthesis of the female hormone oestrogen, in peripheral tissues, such as fat cells and also by some breast cancer cells, preventing the formation of oestrogen and helping to prevent growth of oestrogen-dependent breast tumours.  Femistra tablets 1mg are used as first-line therapy for early, advanced or metastatic breast cancer, also in conjunction with other breast cancer treatment (tamoxifen) or if tamoxifen therapy has not helped prevent progression of the tumour. 

What are the side effects of Femistra?

The most commonly reported side effects when taking Femistra tablets 1mg include hot flushes, joint pain or stiffness, myalgia (muscle pain), skin rash, gastrointestinal upset (nausea, vomiting, diarrhoea), headache, feeling weak (asthenia), vaginal dryness and bleeding, carpal tunnel syndrome, sleepiness, hair loss, anorexia.

When should Femistra not be used?

You should not use Femistra tablets 1mg if you:

• are allergic to anastrozole or any ingredients in Femistra
• are premenopausal, pregnant or breastfeeding
• have kidney or liver disease
• are taking medicines that interact with Femistra including oestrogen containing medication, tamoxifen, another breast cancer drug

How should Femistra be taken?

You should take your Femistra tablets 1mg swallowed whole with a glass of water once a day with or without food.  You should continue taking your Femistra tablets 1mg for as long as recommended by your doctor, but in early cases of breast cancer, for no longer than 5 years.

How long should you take Femistra?

You should continue taking your Femistra tablets 1mg for as long as recommended by your doctor, but in early cases of breast cancer, for no longer than 5 years.

Missed dose of Femistra?

If you miss a dose of Femistra tablets 1mg take it as soon as you remember, unless it is time to take the next dose, then skip the missed dose.  Do not take a double dose.

How should Femistra be stored?

You should store your Femistra tablets 1mg below 25°C in a cool dry place.