Dom-Letrozole: Uses, Side Effects and Dosage

ABOUT THIS MEDICATION

What Dom-LETROZOLE is used for:

• The adjuvant treatment of postmenopausal women with

  hormone receptor-positive early breast cancer;

• The extended adjuvant treatment of hormone receptor

  positive early breast cancer in postmenopausal women who have received approximately 5 years of prior standard adjuvant tamoxifen therapy;

• The first-line therapy in postmenopausal women with

  advanced breast cancer; and

• The hormonal treatment of advanced metastatic breast

  cancer in women with natural or artificially-induced postmenopausal status, who have disease progression following antiestrogen therapy.

What does Dom-LETROZOLE do:

Estrogen is a normally occurring female sex hormone that stimulates normal breast tissue and the growth of some types of breast cancer. Dom-LETROZOLE is an aromatase inhibitor which acts by binding to aromatase, a substance needed to make estrogen. As a result, the production of estrogen and the growth of breast cancer are reduced.

What is adjuvant therapy:

Adjuvant therapy in breast cancer refers to treatment following breast surgery (the primary or initial treatment) in order to reduce the risk of recurrence. The purpose of adjuvant therapy with letrozole is to treat hormone receptor-positive early breast cancer, after surgery, in postmenopausal women to reduce the risk of recurrence.

What is extended adjuvant therapy:

The purpose of extended adjuvant therapy with letrozole is to treat hormone receptor-positive early breast cancer in postmenopausal women who have received approximately 5 years of prior standard adjuvant tamoxifen therapy in order to prevent recurrence. Treating breast cancer with letrozole beyond the standard 5 years of hormone therapy is called "extended adjuvant therapy".

When it should not be used:

adolescents under 18 years of age.

Do not take Dom-LETROZOLE if you:

• have ever had an unusual or allergic reaction to letrozole or any other ingredient in Dom-LETROZOLE;
• still have menstrual periods;

• are pregnant or breast-feeding, as Dom-LETROZOLE may harm your baby.

What the medicinal ingredient is:

Letrozole

What the nonmedicinal ingredients are:

Dom-LETROZOLE also contains the following non-medicinal ingredients needed to make the tablets: colloidal anhydrous silica, FD&C yellow No. 5 (tartrazine) Aluminum Lake, hypromellose, lactose, magnesium stearate, microcrystalline cellulose, polyethylene glycol, red iron oxide, sodium starch glycolate, titanium dioxide and yellow iron oxide.

What dosage forms it comes in:

Tablets: 2.5 mg

WARNINGS AND PRECAUTIONS

Serious Warnings and Precautions

Dom-LETROZOLE should be used under the supervision of a doctor experienced in the use of anti-cancer drugs.

Dom-LETROZOLE reduces blood estrogen levels which may cause a reduction in bone mineral density and a potential increase in bone loss (osteoporosis) and/or bone fractures.

BEFORE you use Dom-LETROZOLE talk to your doctor or pharmacist if:

The use of aromatase inhibitors, including letrozole, may increase the risk of cardiovascular events compared to tamoxifen, such as heart attacks and stroke. Women at risk of heart disease should be carefully monitored by their doctor.

You should not use Dom-LETROZOLE if you may become pregnant, are pregnant and/or breastfeeding. There is a potential risk of harm to you and the fetus, including risk of fetal malformations. If you have the potential to become pregnant (this includes women who are perimenopausal or who recently became postmenopausal), you should discuss with your doctor about the need for effective contraception.

If there is exposure to Dom-LETROZOLE during pregnancy, you should contact your doctor immediately to discuss the potential of harm to your fetus and potential risk for loss of the pregnancy.

adolescents under 18 years of age.

Before you take Dom-LETROZOLE:

Tell your doctor if you:

• have a serious kidney or serious liver disease;
• are taking hormone replacement therapy;
• are taking other medication to treat your cancer;

• have a personal or family history of osteoporosis or have

  ever been diagnosed with low bone density or have a recent history of fractures (in order for your doctor to assess your bone health on a regular basis);

• have a personal or family history of high blood cholesterol

  or lipid levels. Dom-LETROZOLE may increase lipid levels;

• have or have had cardiovascular or heart disease including

  any of the following: heart attack, stroke or uncontrolled blood pressure. Dom-LETROZOLE may increase the risk of cardiovascular or heart diseases;

• have an intolerance to milk sugar (lactose);
• have pain in bones, or joints or muscles.

Driving a vehicle or using machinery:

Dom-LETROZOLE tablets are unlikely to affect your ability to drive a car or to use machinery. However, some patients may occasionally feel tired, dizzy, sleepy or experience visual disorders. If this happens, you should not drive or operate any tools or machinery until you feel normal again.

INTERACTIONS WITH THIS MEDICATION

Please tell your doctor or pharmacist if you are taking or have recently taken any other prescription or over-the-counter medicines, vitamins or natural health products during your treatment with Dom-LETROZOLE.

PROPER USE OF THIS MEDICATION

Usual dose:

The usual dosage is one tablet of Dom-LETROZOLE to be taken once daily. The tablet should be swallowed whole with a small glass of water. You can take Dom-LETROZOLE with or without food. It is best to take Dom-LETROZOLE at about the same time every day.

Overdose:

If overdosage is known or suspected, contact your doctor or the nearest poison control centre for advice immediately. Show the pack of tablets. Medical treatment may be necessary.

Missed Dose:

If you forget to take a dose of Dom-LETROZOLE, don't worry, take the missed dose as soon as you remember. However, if it is almost time for the next dose (e.g. within 2

or 3 hours), skip the missed dose and go back to your regular dosage schedule. Do not take a double dose to make up for the one that you missed.

SIDE EFFECTS AND WHAT TO DO ABOUT THEM

Like all medicines, Dom-LETROZOLE can have some side effects. Most side effects that have been observed were mild to moderate and will generally disappear after a few days to a few weeks of treatment. Check with your doctor if the unwanted effects do not go away during treatment or become bothersome.

Some side effects, such as hot flushes, hair loss or vaginal bleeding may be due to the lack of estrogen in your body.

Very common side effects (they affect more than 10 in every 100 patients)

• hot flushes
• night sweats
• pain in bones and joints.

Common side effects (they affect between 1 to 10 in every 100 patients)

• headache
• rash
• dizziness
• generally feeling unwell
• gastrointestinal disorders (such as, nausea, vomiting, indigestion, constipation, diarrhea)
• increase in or loss of appetite
• increased blood sugar (hyperglycaemia)
• urinary incontinence
• pain in muscles
• bone loss (osteoporosis)
• bone fractures
• depression
• weight increase
• anxiety
• insomnia
• hair loss
• fatigue
• increased sweating
• high level of cholesterol (hypercholesterolemia).

Uncommon side effects (they affect between 1 to 10 in every 1000 patients)

• nervous disorders (such as nervousness, irritability, drowsiness)
• pain or burning sensation in the hands or wrists (carpal tunnel syndrome)
• reduced sense of touch (dysaesthesia)
• eye irritation
• palpitations, rapid heart rate
• raised blood pressure (hypertension)
• dry skin, itchy rash (urticaria), rapid swelling of face, lips, tongue, throat (angioedema)
• severe allergic reaction (anaphylactic reaction)
• vaginal disorders (such as bleeding, discharge or dryness)
• abdominal pain
• joint stiffness (arthritis)
• breast pain
• fever
• thirst, taste disorder, dry mouth
• dryness of mucous membranes
• weight decrease
• urinary tract infection, increased frequency of urination
• cough
• abnormal liver function test results (blood test disorders).

Side effects with frequency not known

• trigger finger, a condition in which your finger or thumb catches in a bent position.

If you notice any other side effects not listed in this leaflet, please tell your doctor or pharmacist.

This is not a complete list of side effects. For any unexpected effects while taking Dom-LETROZOLE, contact your doctor or pharmacist.

HOW TO STORE IT

Store your tablets in a dry place at room temperature 15°C to 30°C. Avoid places where the temperature may rise above 30°C. Protect from moisture.

Keep this medicine out of the reach and sight of children and pets.

Expiry date:

Do not take Dom-LETROZOLE after the expiry date which is stated on the carton after EXP. The expiry date refers to the last day of the month. Remember to take any unused medication back to your pharmacist.

REPORTING SUSPECTED SIDE EFFECTS

MORE INFORMATION

This document plus the full product monograph, prepared for health professionals, can be obtained by contacting the sponsor, Dominion Pharmacal at, 1-888-550-6060.

Montreal Quebec

H4P 2T4

Last revised: February 5, 2013