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Package leaflet: Information for the patient

Azathioprine Tablets 25 mg
Azathioprine Tablets 50 mg

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 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:
1. What Azathioprine is and what it is used for
2. What you need to know before you take
3. How to take Azathioprine
4. Possible side effects
5. How to store Azathioprine
6. Contents of the pack and other information

1. What Azathioprine is and what it is
used for
Azathioprine belongs to a group of medicines
called immunosuppressants. Azathioprine helps to
reduce or suppress your body’s own immune system.
Your immune system helps to protect you against
infections. However, sometimes it can produce illness
and unwanted effects. For example, if you have just
had an organ transplant, your immune system will try
to reject the new organ. Azathioprine helps to prevent
this immune response, and so allows the organ to
carry on working. It is therefore used together with
other medicines such as corticosteroids to:
• improve the survival of organ transplants
Azathioprine is also used to treat conditions caused
by your immune system over reacting or reacting
abnormally. For example:
• rheumatoid arthritis (inflammation and pain in
your joints)

• hepatitis (inflamed liver)
• systemic lupus erythematosus (a disease which
affects your skin and major organs)
• blood disorders such as thrombocytopenia (reduced
numbers of blood cells called platelets). This
can affect blood clotting and increase the risk of
bleeding or bruising.
• haemolytic anaemia (when you do not have enough
red blood cells)
• pemphigus (blisters and sores on your skin)
• dermatomyositis (inflammation of your muscles
and skin)
• polyarteritis nodosa (inflammation of your
blood vessels)
For these conditions, Azathioprine may be used alone,
or in combination with other medicines.

2. What you need to know before you
take Azathioprine
Do not take Azathioprine if you
• are allergic to azathioprine, to mercaptopurine
(a medicine used to treat leukaemia, a cancer of the
white blood cells) or any of the other ingredients of
this medicine (listed in section 6).
• are pregnant or intend to become pregnant
• are breast-feeding.

Warnings and precautions
Talk to your doctor or pharmacist before taking this
medicine if you:
• know you have a metabolic abnormality called
Lesch-Nyhan syndrome. Azathioprine is not
recommended if you have this condition.
• know you have a shortage of a liver enzyme called
thiopurine methyltransferase (TPMT). TPMT breaks
down azathioprine and other medicines.
• have liver or kidney disease. You may have to take a
lower dose and your doctor will closely monitor you.
• have ever suffered from chickenpox or shingles.
If you are receiving immunosuppressive therapy,
taking Azathioprine could put you at greater risk of:
• tumours, including skin cancer. Therefore, when
taking Azathioprine, avoid excessive exposure to
sunlight, wear protective clothing and use protective
sunscreen with a high protection factor.

• lymphoproliferative disorders
* treatment with Azathioprine increases your risk of
getting a type of cancer called lymphoproliferative
disorder. With treatment regimen containing
multiple immunosuppressants (including
thiopurines), this may lead to death.
* A combination of multiple immunosuppressants,
given concomitantly increases the risk of
disorders of the lymph system due to a viral
infection (Epstein-Barr virus (EBV)-associated
lymphoproliferative disorders).
Taking Azathioprine could put you at greater risk of:
• developing a serious condition called Macrophage
Activation Syndrome (excessive activation of white
blood cells associated with inflammation), which usually
occurs in people who have certain types of arthritis.

Chickenpox /Shingles infection
Infection with chickenpox or shingles can become
severe in patients taking immunosuppressive
medicine. Therefore you should avoid contact with
anyone suffering from chickenpox or shingles.
Your doctor will need to monitor you closely
throughout your treatment. You should therefore visit
your doctor regularly whilst taking Azathioprine so
your condition can be checked. You will need to have
your blood count checked at least once a week for the
first two months of treatment and then monthly.

Other medicines and Azathioprine

Tell your doctor or pharmacist if you are taking, have
recently taken or might take any other medicines,
including medicines obtained without a prescription,
or the following:
• other immunosuppressants e.g. ciclosporin,
methotrexate, tacrolimus
• medicines to treat cancer e.g. doxorubicin
• allopurinol, oxipurinol or thiopurinol (for gout or
kidney stones)
• cimetidine (for gut or stomach ulcers)
• furosemide (‘water tablets’)
• penicillamine (for rheumatoid arthritis)
• warfarin (to ‘thin’ the blood)
• captopril (for blood pressure or heart failure)
• indomethacin (an anti-inflammatory)
• co-trimoxazole (an antibiotic)
• mesalazine, olsalazine, sulfasalazine or balsalazide
(mainly used to treat ulcerative colitis).

If you are going to have an operation, tell your
doctor or the hospital staff as Azathioprine can
interact with medicines called muscle relaxants (e.g.
succinylcholine or tubocurarine), which you might be
given during your operation.
If you are going to have a vaccination, tell your doctor
as some vaccines should not be given or may be less
effective, when given together with Azathioprine.

Pregnancy and breast-feeding

Do not take Azathioprine if you are pregnant, become
pregnant, or suspect you may already be pregnant as
the product could harm your baby (see section 2 “Do
not take Azathioprine” above). Contact your doctor as
soon as possible for advice. Do not take Azathioprine
if you are planning to have a baby. This applies to
both men and women.
You and your partner must use a reliable method of
contraception whilst taking Azathioprine.
Do not breast-feed your baby. Azathioprine may pass
into breast milk.

Driving and using machines

Do not drive or operate machinery if you feel dizzy
while taking this medicine.

3. How to take Azathioprine
Always take this medicine exactly as your doctor or
pharmacist has told you. Check with your doctor or
pharmacist if you are not sure.

Adults, adolescents and children

Your dose will be adjusted depending on your weight.
The recommended doses are:
To prevent organ rejection
The recommended starting dose is up to 5 mg per kg
of body weight per day. Your doctor will then assess
your response to Azathioprine and choose the best
dose for you. This may take weeks or months. After
this assessment your dose will usually be between
1 and 4 mg per kg of body weight per day.
Other conditions
The recommended starting dose is between 1 and
3 mg per kg of body weight per day. Your doctor will
adjust the dose until it is right for you. Your doctor will
prescribe the lowest dose that is effective to treat your
condition. If there is no improvement within three
months, your doctor may stop giving you this medicine.

Older people or people with kidney or
liver disease
If you are elderly or you have kidney or liver disease,
you may be started on a lower dose of Azathioprine.
Your doctor will monitor your blood and liver function
carefully. Your dose may be reduced further if there
are any signs that your blood or liver is affected.

Taking Azathioprine
• Swallow the tablets whole with a glass of water. Do
not break, chew or crush them.
• The 50 mg tablets have a score line but this is not
intended for breaking the tablet.
• If you feel sick after taking your Azathioprine, it
should help to take your tablets after meals.

If you take more Azathioprine than you should
Contact your doctor or nearest hospital emergency
department immediately. Take the container and any
remaining tablets with you. Symptoms of overdose
include nausea (feeling sick), vomiting and diarrhoea,
lack of white blood cells which may cause frequent
infections such as fever, severe chills, sore throat or
mouth ulcers, disturbances of your liver function,
bruising and bleeding.

If you forget to take Azathioprine
If you forget to take your tablets, take the missed
dose as soon as you remember. If it is nearly time for
your next dose and if you take only one dose a day,
do not double your next dose, carry on as usual and
check with your doctor. If you miss a dose, check with
your doctor.

If you stop taking Azathioprine

Do not stop taking this medicine without talking to
your doctor. You may need to take it indefinitely to
help stop transplant rejection.
If you have any further questions on the use of this
medicine, ask your doctor or pharmacist.

4. Possible side effects
Like all medicines, this medicine can cause side
effects, although not everybody gets them.
If any of the following happen stop taking
Azathioprine and tell your doctor immediately or go
to your nearest hospital emergency department:

Very common (may affect more than 1 in 10 people):
• you have any signs of a viral, fungal or bacterial
infection or fever. Infections are very common
if you are taking Azathioprine after an organ
transplant, and with another immunosuppressant
or corticosteroid.
• low levels of white blood cells that means you are
more likely to catch infections.
Common (may affect up to 1 in 10 people):
• reduction in blood platelets which increase the risk
of bleeding or bruising
Uncommon (may affect up to 1 in 100 people):
• allergic reactions which may cause: feeling generally
unwell, dizziness, nausea (feeling sick), vomiting
(being sick), diarrhoea, fever, chills, rash or red spots,
muscle or joint pain, problems with your kidneys
(which may cause changes in the amount and colour
of your urine), problems with your liver (which may
cause yellowing of your skin and whites of your
eyes), or a fall in blood pressure (hypotension) which
may cause light-headedness or sweating. Your
doctor may tell you to stop taking Azathioprine if
you develop these symptoms.
• inflamed pancreas which causes severe pain in the
abdomen and back.
• cholestasis (when the flow of bile is blocked) or
abnormal liver enzyme levels in the blood. The
symptoms of these conditions include dark urine,
pale stools, itchy skin and yellowing of your skin and
whites of your eyes.
Rare (may affect up to 1 in 1,000 people):
• various types of cancers including blood, lymph and
skin cancers
• stomach pain and swelling; yellowing of the skin or
whites of the eyes. These may be due to problems
with your liver. Azathioprine can cause a rare but
severe form of liver disease which can be fatal.
• disturbances of the bowel such as inflammation
which causes abdominal pain, fever, discomfort,
vomiting or diarrhoea. This is more likely to happen
if you also take high doses of corticosteroids. Also,
severe diarrhoea may happen, especially if you are
being treated for inflammatory bowel disease.
• severe reduction of all types of blood cells which
can cause weakness, bruising or make infections
more likely.


• severe blistering of the skin, mouth, throat, nose,
genitals and conjunctivitis (red and swollen eyes).

6. Contents of the pack and other

Very rare (may affect up to 1 in 1,000 people):
• inflammation of the lungs which can cause
weakness, breathlessness, cough and fever.

What Azathioprine contains

Stop taking Azathioprine and tell your doctor
immediately if you come into contact with anyone
who is suffering from chickenpox or shingles.

The other ingredients are maize starch,
microcrystalline cellulose, mannitol, povidone K25,
croscarmellose sodium and stearylfumarate sodium.
The film-coating contains hypromellose and macrogol.

Other side effects include:

Rare side effects (may affect up to 1 in
1,000 people):
• hair loss, especially if you are also taking another
immunosuppressant. Your hair will usually grow
back even when you carry on taking Azathioprine.
• increased sensitivity of the skin to sunlight.
Not known (frequency cannot be estimated from
the available data):
• nausea (feeling sick) especially when first taking
Azathioprine. This can be relieved if you take your
tablets after meals.

Reporting of side effects

If you get any side effects, talk to your doctor,
pharmacist or nurse. 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.

5. How to store Azathioprine
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 after EXP. The expiry date refers
to the last day of that month.
This medicinal product does not require any special
storage conditions.
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 protect the environment.

The active substance is azathioprine. Each tablet
contains either 25 mg or 50 mg azathioprine.

What Azathioprine looks like and contents of
the pack
Your medicine comes as a pale yellow, round,
film-coated tablet.

The 25 mg tablet is marked 'AE' over '25' on one side
with a 'G' on the other.
The 50 mg tablet is marked 'AE' over '50' on one side
and a scoreline on the reverse.
Azathioprine is available in blister packs or plastic
containers of 28, 30, 50, 56, 60, 84, 90, 100, 112, 168,
500 and 1,000 tablets. Not all pack sizes may be

Marketing Authorisation Holder
Station Close
Potters Bar
Herts EN6 1TL


Generics [UK] Limited
Station Close
Potters Bar
Herts EN6 1TL
Gerard Laboratories
35/36 Baldoyle Industrial Estate,
Grange Road, Dublin 13,
Delpharm Lille S.A.S
Parc d'activités, Roubaix-Est, 22 rue de Toufflers CS 50070, 59452 Lys-Lez-Lannoy
This leaflet was last revised in December 2016


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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.