Skip to Content

UK Edition. Click here for US version.


Active substance(s): TAMOXIFEN CITRATE

View full screen / Print PDF » Download PDF ⇩
TAMOXIFEN 10 mg, 20 mg
Package leaflet:
Information for the patient
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
• 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 yours.
• 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.
What is in this leaflet

What Tamoxifen is and what it is used for
What you need to know before you take Tamoxifen
How to take Tamoxifen
Possible side effects
How to store Tamoxifen
Contents of the pack and other information


What Tamoxifen is and what it is used for

• The name of your medicine is Tamoxifen Tablets and they
belong to a group of drugs called anti-oestrogens.
• Tamoxifen is used to treat:
• breast cancer
• certain forms of infertility.


What you need to know before you take

• Quinidine (for example used in the treatment of cardiac
• Cinacalcet (for treatment of disorders of the parathyroid
• any anti-coagulants (used to treat and prevent abnormal
blood clotting) e.g. warfarin
• any cytotoxic drugs (used to kill cancer cells)
• Rifampicin (used to treat tuberculosis).
Pregnancy and breast-feeding
You should not take Tamoxifen if you are pregnant or
If you are pregnant or breast-feeding, think you may be
pregnant or are planning to have a baby, ask your doctor or
pharmacist for advice before taking this medicine. You
should use an effective method of non-hormonal
contraception such as the barrier method (e.g. the
diaphragm or condoms) whilst being treated with Tamoxifen
and for 2 months after treatment has stopped.
Driving and using machines
Tamoxifen is not known to affect your ability to drive or
operate machinery.


How to take Tamoxifen

Always take this medicine exactly as your doctor has told
you. Check with your doctor or pharmacist if you are not
Before commencing any treatment, pregnancy must be
excluded by having a pregnancy test if there is any chance
that you could be pregnant.
The tablets should be swallowed preferably with a glass of
The recommended dose is:

Adults and the elderly
• For the treatment of breast cancer
20 mg a day. Your doctor will assess whether this dose is
appropriate for you.
• For the treatment of infertility, if you have regular periods
10 mg twice a day or 20 mg once a day on days 2, 3, 4 and 5
of the menstrual cycle (the first day of bleeding is counted as
day 1 of the cycle). If the initial course of treatment is
unsuccessful it may be repeated, with higher doses if
necessary, up to a maximum of 80 mg daily in single or
divided doses.
Warnings and precautions
• If you do not have regular periods
Talk to your doctor or pharmacist before taking Tamoxifen:
10 mg twice a day or 20 mg once a day for four days. This
• if you have or any member of your family has a history of
initial course of treatment may begin on any day.
blood clots, symptoms of which include pain or swelling in If you do not menstruate after the initial course of treatment,
the calf of one leg and/or sudden breathlessness. If you
your doctor may give you a further course with increased
experience these symptoms while taking Tamoxifen, you
dosage starting 45 days later. If you do menstruate after the
should speak to your doctor immediately
initial course of treatment, the next course should start on
• if you are severely overweight, if you are elderly, following day 2 of that menstrual cycle.
surgery or if you are immobile as there is an increased
you take more Tamoxifen than you should
chance of a blood clot forming
If you (or someone else) swallow a lot of the tablets all
• if you are being treated for breast cancer and are also
together, or if you think a child has swallowed any of the
receiving chemotherapy, as your doctor may also
tablets, contact your nearest hospital casualty department or
prescribe an anticoagulant to prevent blood clots
your doctor immediately. Please take this leaflet, any
• if you are taking any of the following drugs paroxetine,
remaining tablets and the container with you to the hospital
fluoxetine (e.g. antidepressants), bupropion
or doctor so that they know which tablets were consumed.
(antidepressant or aid to smoking cessation), quinidine
(used in the treatment of cardiac arrhythmia) and
If you forget to take Tamoxifen
cincalet/cinacalcet (for treatment of disorders of the
If you forget to take a tablet, take one as soon as you
parathryroid gland. Co-administration should be avoided
remember, unless it is nearly time to take the next one. Do
because a reduction of the effect of Tamoxifen cannot be not take a double dose to make up for a forgotten dose.
If you stop taking Tamoxifen
• if you have experienced abnormal vaginal bleeding
including menstrual irregularities, vaginal discharge, and Do not stop taking your medicine without talking to your
pelvic pain or pressure while taking Tamoxifen in the past. doctor first even if you feel better.
If you have any further questions on the use of this medicine,
If you experience any of these symptoms when taking
ask your doctor or pharmacist.
Tamoxifen you should speak to your doctor immediately.
Do NOT take Tamoxifen:
• if you are allergic to tamoxifen citrate or any of the other
ingredients of this medicine (listed in section 6)
• if you are to be treated for infertility and you or your family
have a history of blood clots or a known inherited
condition leading to an increased risk of clotting
• if you are pregnant or planning to become pregnant
• if you are taking a medicine called ‘anastrozole’ (used to
treat breast cancer, see section 2 Taking other

If you need to have a liver function test whilst you are taking
these tablets, make sure you have told the doctor that you
are taking Tamoxifen, as it can affect the results of this test.


Possible side effects

Like all medicines, this medicine can cause side effects,
although not everybody gets them.
Other medicines and Tamoxifen
If the following happens, stop taking the tablets and tell your
Please do not take anastrozole (used to treat breast cancer) doctor immediately or go to the casualty department at your
while you are taking this medicine.
nearest hospital:
Tell your doctor or pharmacist if you are taking, have recently • an allergic reaction (swelling of the lips, face or neck
leading to severe difficulty in breathing; skin rash or hives)
taken or might take any other medicines, even those you
• blistering/bleeding of the lips, eyes, nose and genitals
have bought without prescription. In particular, you should
(Stevens-Johnson syndrome).
inform your doctor if you are taking:
• Paroxetine, fluoxetine (e.g. antidepressants)
These are very serious but rare side effects. You may need
• Bupropion (antidepressants or aid to smoking cessation)
urgent medical attention or hospitalisation.

You should speak to your doctor if you notice any of the
following side effects as these are all symptoms of a blood
clot. You may need urgent medical treatment:
• The symptoms of a blood clot include pain and swelling of
the calf or leg, chest pain, being short of breath or
suddenly feeling weak.
Stop taking Tamoxifen and tell your doctor straight away if
you notice any of the following side effects – you may need
urgent medical treatment:
• Symptoms of a stroke. These include sudden onset of the
following: weakness of the arms or legs, being unable to
move the arms or legs, difficulty speaking, walking, or
holding things, or difficulty thinking. These symptoms are
caused by a reduced blood supply in the brain.
You should speak to your doctor or nurse at once if you
notice any of the following gynaecological symptoms:
• Abnormal vaginal bleeding including menstrual
• Vaginal discharge
• A feeling of discomfort in the lower tummy (pelvis) such as
pain or pressure.
These effects may mean that there have been changes to
the lining of your womb (the endometrium). Sometimes
these effects are serious and could include cancer of the
endometrium/uterus. They can happen during or after
treatment with Tamoxifen.
Other side effects:
Very common: may affect more than 1 in 10 people
• Nausea.
• Fluid retention.
• Skin rash.
• Hot flushes.

• Damage to blood vessels causing red or purple dots in
the skin.
• Severe skin disorder. The symptoms include redness,
blistering and peeling.
• Cells normally only found in the lining of the womb
found elsewhere in your body, cysts on the ovaries,
and cancer (the signs of this are given above).
• Non-cancerous mass in the inner lining of the vagina
(called vaginal polyp).
Very rare: may affect up to 1 in 10,000 people
• Inflammation of the skin characterized by rash or
erythema, very often on areas exposed to light (a
condition called cutaneous lupus erythematosus).
• A skin condition characterised by skin blisters in areas
exposed to the light, this is due to the increased liver
production of a special group of cell pigments (called
Not known: frequency cannot be estimated from the
available data
• Gastro-intestinal intolerance
• Bone pain
Do not be concerned by this list of possible side effects. You
may not get any of them.
Reporting of side effects
If you get any side effects, talk to your doctor or pharmacist.
This includes any possible 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.


How to store Tamoxifen

Common: may affect up to 1 in 10 people
• Anaemia (a blood problem which means you have too
few red blood cells).
• Changes in vision due to cataracts or changes to the
retina of your eye.
• Increased amounts of fats in your blood (shown by
blood tests).
• Leg cramp.
• Changes in the womb (including changes to its lining
and benign growths).
• Headache.
• Feeling light-headed.
• Itching of the genitals.
• Thinning of the hair.
• Vomiting.
• Diarrhoea.
• Constipation.
• Changes in blood tests of liver function.
• Formation of fatty liver cells.
• Muscle pain.

Keep this medicine out of the sight and reach of children.
DO NOT store above 25°C, and keep the tablets in the
original bottle or carton supplied. Do not transfer them to
another container.
Do not use this medicine after the expiry date that is stated
on the carton. The expiry date refers to the last day of that
Do not throw away any medicines via wastewater or
household waste. Ask your pharmacist how to throw away
medicines you no longer use. These measures will help to
protect the environment.

• Problems with the nerve that connects your retina to
your brain.
• Swelling of the optic nerve.
• On occasions more severe liver diseases have
occurred from which some patients have died. These
liver diseases include inflammation of the liver, liver
cirrhosis, liver cell damage, reduced bile formation,
and failure of the liver. Symptoms may include a
general feeling of being unwell, with or without
jaundice (yellowing of the skin and eyes).

This leaflet was last revised in February 2016


Contents of the pack and other information

What Tamoxifen tablets contain:
• The active ingredient is either 15.2 mg of Tamoxifen citrate
which is equivalent to 10 mg of tamoxifen, 30.4 mg of
Tamoxifen citrate which is equivalent to 20 mg of
tamoxifen or 60.8 mg of Tamoxifen citrate which is
equivalent to 40 mg of tamoxifen.
• The other ingredients are mannitol (E421), povidone
Uncommon: may affect up to 1 in 100 people
(E1201), sodium starch glycolate, colloidal silicon dioxide
• Blood problems. This can make you bruise more easily,
(E551), magnesium stearate (E572), hypromellose (E464),
get serious infections, or feel very tired or breathless.
polyethylene glycol and the colour, titanium dioxide (E171).
• Changes to your vision and difficulty seeing.
What Tamoxifen tablets look like and contents of the pack:
• Swelling of the pancreas. This may cause moderate to
• Tamoxifen 10 mg Tablet: Round biconvex white coated
severe pain in the stomach.
tablets 7 mm diameter with one face blank, the reverse
• Changes in the amount of calcium in your blood. The
face marked '10' above score line and 'T' below.
signs may include feeling very sick, being sick a lot or
• Tamoxifen 20 mg Tablet: Round biconvex white coated
being thirsty. Tell your doctor if this happens because
tablets 9.5 mm diameter with one face blank, the reverse
he or she may want you to have blood tests.
face marked '20' above score line and 'T' below.
• Inflammation of the lungs. The symptoms may be like
• Round biconvex white coated tablets 11.1 mm diameter
pneumonia (such as feeling short of breath and
with one face blank, the reverse face marked '40' above the
score line and 'T' below.
• Liver cirrhosis (problems with your liver).
• The tablets are available in packs of 30 and 250 tablets.
Rare: may affect up to 1 in 1,000 people
Not all pack sizes may be marketed.
• Severe blood problems. This can make you bruise
Marketing Authorisation Holder and Manufacturer
more easily, get serious infections, or feel very tired or
Marketing Authorisation holder and company responsible for
manufacture: TEVA UK Limited, Eastbourne, BN22 9AG.
• Changes to the cornea of your eye.
PL 00289/0477-0479

62929 X

Expand view ⇕

Source: Medicines and Healthcare Products Regulatory Agency

Disclaimer: Every effort has been made to ensure that the information provided here is accurate, up-to-date and complete, but no guarantee is made to that effect. Drug information contained herein may be time sensitive. This information has been compiled for use by healthcare practitioners and consumers in the United States. The absence of a warning for a given drug or combination thereof in no way should be construed to indicate that the drug or combination is safe, effective or appropriate for any given patient. If you have questions about the substances you are taking, check with your doctor, nurse or pharmacist.