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Tamoxifen 20 mg Tablets


(tamoxifen citrate)
Read all of this leaflet carefully before you start taking this medicine
because it contains important information for you.
- Keep this leaflet. You may need to read it again.
- If you have any further questions, ask your doctor or pharmacist.
- This medicine has been prescribed for you only. Do not pass it on to
others. It may harm them, even if their signs of illness are the same as
- If you get any side effects, talk to your doctor or pharmacist. This includes
any possible side effects not listed in this leaflet. See section 4.
This medicine is called Tamoxifen 20mg Tablets but will be referred to as
Tamoxifen throughout the leaflet.
What is in this leaflet:
1. What Tamoxifen is and what it is used for
2. What you need to know before you take Tamoxifen
3. How to take Tamoxifen
4. Possible side effects
5. How to store Tamoxifen
6. Contents of the pack and other information
Tamoxifen belongs to a group of medicines called anti-oestrogens. Antioestrogens block the effects of a hormone called oestrogen in your body.
Tamoxifen is used:
- in the treatment of breast cancer
- to stimulate ovulation (the production of an egg) in women who suffer from
a condition called anovulatory infertility. This is when you may have
regular, or irregular, menstruation (periods) but you do not ovulate (release
an egg).
Do not take Tamoxifen if you:
- are allergic to tamoxifen or any of the other ingredients of this medicine
(listed in section 6).
- are pregnant (see ‘Pregnancy and breast-feeding’ in section 2 of this leaflet
for further information). If you are a woman of child-bearing age, a
pregnancy test should normally be taken to confirm if you are pregnant
before starting treatment.
- are taking another medicine for the treatment of breast cancer known as
- are taking Tamoxifen for treating your infertility and have a family history of
blood clots.
Warnings and precautions
Talk to your doctor or pharmacist before taking Tamoxifen
When you take tamoxifen you have a 2 to 3 times increased risk of a
developing a blood clot in your vein. You should speak to your doctor before
taking this medicine as the risk is greater if:
- you are elderly
- you or a member of your family have had a blood clot in the past
- you are very overweight (obese), smoke (or have smoked in the past) or
have heart or circulatory problems
- you are being given chemotherapy for your breast cancer
If your doctor considers that you are at risk of blood clots, they may give you
an anticoagulant. This is a medicine that thins your blood and reduces your
risk of forming a blood clot.
When you take tamoxifen, co-administration with the following drugs should
be avoided because a reduction of the effect of tamoxifen cannot be
excluded: paroxetine, fluoxetine (e.g. antidepressants), bupropion
(antidepressant or aid to smoking cessation), quinidine (for example used in
the treatment of cardiac arrhythmia) and cincalet/cinacalcet (for treatment of
disorders of the parathyroid gland).
When you take tamoxifen to treat breast cancer, you may stop having your
monthly periods.
Surgery and immobility
If you are to have surgery, or you will be unable to move around for a long
time, you should take the following precautions:
- If you are taking tamoxifen for infertility: you should stop taking tamoxifen
at least 6 weeks beforehand and you should not start taking tamoxifen
again until you are fully mobile again.
- If you are taking tamoxifen for breast cancer: your doctor may decide that it
is better to carry on taking tamoxifen. You may be given special stockings
called compression stockings to wear whilst you are in hospital or they may
give you an anticoagulant. These reduce the risk of a blood clot.
Other medicines and Tamoxifen
Tell your doctor or pharmacist if you are taking, have recently taken or might
take any other medicines, including medicines obtained without a
Do not take tamoxifen if you are taking another medicine for the treatment of
breast cancer known as anastrozole.
Also, tell your doctor if you are taking:
- Paroxetine, fluoxetine (e.g. selective serotonin reuptake inhibitor (SSRI)
- Bupropion (antidepressant or aid to smoking cessation)
- Quinidine (for example used in the treatment of cardiac arrhythmia)
- Cinacalcet (for treatment of disorders of the parathyroid gland)
or the following:
- anticoagulant medicines (to thin your blood), e.g. warfarin. Tamoxifen may
increase the effects of these medicines. Your doctor will monitor your blood
regularly, especially when you start or stop treatment.
- cytotoxic agents (used to treat cancer). These medicines increase the risk
of a blood clot. Your doctor may give you another medicine to stop your
blood clotting too easily.
- rifampicin, an antibiotic used to treat infections such as tuberculosis (TB)
Pregnancy and breast-feeding
Do not take Tamoxifen if you are pregnant as the product could harm your
If you are taking tamoxifen for the treatment of infertility, you must always
take a pregnancy test before you start to take this medicine. If the result is
positive, or you are not sure, do not take tamoxifen and talk to your doctor.
If you are taking tamoxifen for the treatment of breast cancer and are of
child-bearing age, a pregnancy test should normally be taken before you
start to take this medicine to confirm that you are not pregnant. If you think
you may be pregnant or are planning to have a baby, do not take tamoxifen
and contact your doctor as soon as possible for advice.

When you are taking tamoxifen, if you are sexually active, you should use a
barrier method or other non-hormonal method of contraception (e.g.
After stopping tamoxifen, you should wait at least 2 months before planning
to have a baby.
Do not breast-feed your baby. Tamoxifen may pass into breast milk.
Driving and using machines
Do not drive or operate machinery if you feel light-headed, or you have
eyesight problems while taking this medicine.
Always take this medicine exactly as your doctor or pharmacist has told you.
Check with your doctor or pharmacist if you are not sure.
- Swallow the tablets with a glass of water
- You can take Tamoxifen with or without food
The recommended doses in adults are:
Breast cancer:
20 mg per day.
Anovulatory infertility:
If you have regular periods:
You should take Tamoxifen on the second, third, fourth and fifth days of the
menstrual cycle.
The recommended initial dose is 20 mg daily in either one or two doses.
If this is unsuccessful an increased dose may be given during following
menstrual periods: 40 mg then 80 mg daily in either one or two doses.
If you have irregular periods:
You may start treatment with Tamoxifen on any day. If your first course of
treatment is unsuccessful, you may be given an increased dose after an
interval of 45 days. The higher dose is 40 to 80 mg daily in either one or two
doses. If you respond to treatment by menstruating your next course of
treatment should start on the second day of your cycle.
You will usually be given the normal adult dose.
Use in children and adolescents
Children and adolescents should not take Tamoxifen.
If you take more Tamoxifen than you should
Contact your doctor or nearest hospital emergency department immediately.
Take the container and any remaining tablets with you. In some cases,
tamoxifen may affect the electrical activity of the heart which may be seen in
tests or you may notice changes in the heart beat or rate.
If you forget to take Tamoxifen
Take the next dose as soon as you remember unless it is almost time for
your next dose. Do not take a double dose to make up for a forgotten dose.
If you stop taking Tamoxifen
Do not stop taking Tamoxifen without speaking to your doctor first.
If you have any further questions on the use of this medicine, ask your doctor
or pharmacist.
Like all medicines, this medicine can cause side effects, although not
everybody gets them.
If any of the following happen, stop taking Tamoxifen and tell your doctor
immediately or go to your nearest hospital emergency department:
Very common (may affect more than 1 in 10 people):
- vaginal bleeding
Common (may affect up to 1 in 10 people):
- severe allergic symptoms such as sudden breathing difficulties, dizziness,
swelling of the mouth, face or throat, hives, or a skin rash similar to nettle
- blood clots in small or large blood vessels. If they occur in the larger blood
vessels, you may notice symptoms such as swelling of the calf or leg,
chest pain, coughing up blood, shortness of breath, sudden weakness, or
sudden swelling of the hands, feet or ankles. You are more likely to suffer
from these if you use tamoxifen in combination with cytotoxic (anti-cancer)
- sudden confusion, weakness, loss of strength particularly on one side of
the body, confused or loss of speech – these may be signs of a reduction
on the blood flow to the brain.
- eye problems due to retinopathy (when the retina in the eye breaks down)
Uncommon (may affect up to 1 in 100 people):
- cancer of the lining of the womb (the endometrium)
- reduction in white blood cells, which may cause more infections than usual
such as fever, severe chills, sore throat or mouth ulcers
- swelling of the pancreas (pancreatitis) that may result in stomach pain
radiating to the back, fever and nausea (feeling sick)
- inflammation of the lungs (pneumonitis) may occur, which may cause a dry
cough, progressive difficulty in breathing, swelling of the ends of the
fingers, bluish discolouration of the skin and fever
Rare (may affect up to up to 1 in 1,000 people):
- severe potentially life-threatening skin rashes, appearing as a skin
condition with severe blisters and bleeding in the lips, eyes, mouth, nose
and genitals (Stevens-Johnson syndrome) or the formation of blisters
between the layers of the skin
- cancer of womb
- swelling of the optic nerve behind the eye, which can cause increasingly
blurred vision.
- damage to, or loss of, nerve cells in the optic nerve, which can lead to loss
of vision
- liver disorders such as cholestasis (when the flow of bile is blocked), injury,
inflammation, death of liver cells or liver failure. You may notice yellowing
of the skin or eyes, pale stools, dark urine or pain in the stomach and
Very rare (may affect up to 1 in 10,000 people):
- condition in which the body’s own immune system becomes overactive and
attacks normal healthy tissue including that of the skin (cutaneous lupus
These side effects are serious. You may need medical attention.
The following side effects generally occur after long-term use with Tamoxifen
and include a range of menstrual disorders (see below). If you still have periods
you may notice that your cycles are disturbed, or may completely stop.

Very common (may affect more than 1 in 10 people):
- vaginal discharge
- hot flushes
- skin rash
- feeling sick
- swollen arms or legs (fluid retention in the body)
- feeling tired
Common (may affect up to 1 in 10 people):
- reduction in red blood cells which can make the skin pale and cause
weakness or breathlessness (anaemia)
- increase in blood fat (triglyceride) levels
- light-headedness, headache
- tingling or pins and needles sensations in the hands and feet
- changes in taste, being sick, diarrhoea, constipation
- hair loss
- tumour pain
- visual disturbance such as cataracts (when the lens of your eye lets
through less light)
- changes in liver enzyme levels (which may be seen in blood tests),
development of “fatty liver” where fatty deposits are seen in the liver
- leg cramps, muscle pain
- genital itching
- uterine fibroids or polyps (non-cancerous growths of the womb), thickening
of the womb lining
Uncommon (may affect up to 1 in 100 people):
- blood disorders which may cause you to bruise or bleed more easily or
without explanation
- scarring of the liver (cirrhosis), normally due to liver damage
- high levels of calcium in your blood.
Rare (may affect up to 1 in 1,000 people):
- short-lived falls in platelet counts (platelets are blood cells)
- changes to the cornea (the outer covering of your eye).
- abnormal or interrupted menstrual cycle (periods) in premenopausal
- swelling of the ovaries, which may cause pain or pressure in the pelvis
- presence of cells from the lining of the womb outside of the womb
- vaginal polyps (non-cancerous growths of the vagina)
- red, often itchy spots, similar to the rash of measles
- inflammation of small blood vessels which may lead to purple discoloration
of the skin
- a worsening or “flare” of the existing cancer tumour
Very rare (may affect up to 1 in 10,000 people):
- inflammation of a vein due to a blood clot (thrombophlebitis).
- blistering of skin which is exposed to sunlight or detachment of the nail
from the nail bed
- radiation recall – skin rash involving redness, swelling, and/or blistering
(like severe sunburn) of the skin after receiving radiation therapy.
Reporting side effects
If you get any side effects, talk to your doctor or pharmacist. This includes
any side effects not listed in this leaflet.
You can also report side effects directly via the Yellow Card Scheme at:
By reporting side effects you can help provide more information on the safety
of this medicine.
Keep this medicine out of the sight and reach of children.
Do not use this medicine after the expiry date which is stated on the carton.
The expiry date refers to the last day of that month.
Do not store above 25°C.
Store in the original package in order to protect from light and moisture.
If the tablets become discoloured or show any other signs of deterioration,
consult your pharmacist who will tell you what to do.
Do not throw away any medicines via wastewater or household waste. Ask
your pharmacist how to throw away medicines you no longer used. These
measures will help protect the environment.
What Tamoxifen contains
The active substance is tamoxifen citrate.
Each tablet contains tamoxifen citrate equivalent to 20 mg tamoxifen.
The other ingredients are mannitol, maize starch, croscarmellose sodium
and magnesium stearate.
What Tamoxifen looks like and contents of the pack
Your medicine comes as white, round, biconvex tablets marked ‘TN|20’ on
one side and ‘G’ on the other.
Tamoxifen is available in blister packs of 30 tablets.
Manufactured by
Mylan B.V., Dieselweg 25, 3752 LB Bunschoten, The Netherlands.
Generics [UK] Ltd, Station Close, Potters Bar, Herts, EN6 1TL. UK.
McDermott Laboratories Ltd t/a Gerard Laboratories, 35/36 Baldoyle
Industrial Estate, Grange Road, Dublin 13, Ireland.
Delpharm Lille S.A.S., ZI Roubaix Est, Rue de Toufflers, 59390 Lys-lezLannoy, France.
Procured from within the EU by Product Licence holder Star Pharmaceuticals
Ltd, 5 Sandridge Close, Harrow, Middlesex HA1 1XD. Repackaged by
Servipharm Ltd.

PL 20636/2855

Leaflet revision and issue date (Ref) 24.11.16[4]

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