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Active substance(s): MERCAPTOPURINE

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Puri-Nethol® 50mg Tablets

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 about your illness or your
medicine, ask your doctor, nurse or pharmacist.
This medicine has been prescribed for you only. Do not pass
it on to others. It may harm them, even if their symptoms
are the same as yours.
If you get any side effects talk to your doctor, nurse or
pharmacist. This includes any possible side effects not listed
in the leaflet. See section 4.

What is in this leaflet:

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

1. What Puri-Nethol is and what it is used for
Puri-Nethol contains a medicine called mercaptopurine. This
belongs to a group of medicines called cytotoxics (also called
chemotherapy). Puri-Nethol is used to treat leukaemia (cancer of
the blood). It works by reducing the number of new blood cells
your body makes.
Puri-Nethol is used for:

Acute myelogenous leukaemia (also called acute
myeloid leukaemia or AML) - a fast growing disease that
increases the number of white blood cells produced by the
bone marrow. This can cause infections and bleeding.

Acute lymphoblastic leukaemia (also called acute
lymphocytic leukaemia or ALL) - a fast-growing disease
which increases the number of immature white blood cells.
These immature white blood cells are unable to grow and
work properly. They therefore cannot fight infections and
may cause bleeding.

Chronic granulocytic leukaemia (also called chronic
myeloid leukaemia) - a disease that increases the number
of white blood cells. This can cause infections and bleeding.
Ask your doctor if you would like more explanation about these

2. What you need to know before you take
Do not take Puri-Nethol:

if you are allergic (hypersensitive) to mercaptopurine or any
of the other ingredients of Puri-Nethol
(listed in section 6)
Do not take if the above applies to you. If you are not sure, talk
to your doctor or pharmacist before taking Puri-Nethol.

Warnings and precautions

Talk to your doctor or pharmacist before taking Puri-Nethol if:

you have a liver problem; your doctor will monitor your liver

you have a condition where your body produces too little of
something called TPMT or ‘thiopurine methyltransferase’
If you are not sure if any of the above apply to you, talk to your
doctor, nurse or pharmacist before taking Puri-Nethol.

Other medicines and Puri-Nethol

Tell your doctor or pharmacist if you are taking, have recently
taken or might take any other medicines, including medicines
obtained without a prescription. This includes herbal medicines.
In particular, tell your doctor or pharmacist if you are taking any
of the following:

methotrexate (used mainly to treat cancers)

other cytotoxic drugs (chemotherapy) - when used with
Puri-Nethol there is a greater chance of side effects, such as
breathing problems

allopurinol, oxipurinol and thiopurinol (used mainly to treat
gout) – when used with Puri-Nethol, only 25 % of the
normal dose of Puri-Nethol should be taken

anticoagulants such as warfarin (used to thin the blood and
prevent blood clots)

olsalazine or mesalazine (used for a bowel problem called
ulcerative colitis)

sulfasalazine (used for rheumatoid arthritis or ulcerative
colitis) ribavirin (used to treat viral infections)

Having vaccines while you are taking Puri-Nethol
If you are going to have a vaccination speak to your doctor or
nurse before you have it. This is because some vaccines (like
polio, measles, mumps and rubella) may give you an infection
if you have them whilst you are taking Puri-Nethol.

Pregnancy, breast-feeding and fertility

Do not take Puri-Nethol if you are planning to have a baby. This
applies to both men and women. Puri-Nethol may harm your
sperm or eggs. Reliable contraceptive precautions must be taken
to avoid pregnancy whilst you or your partner are taking these
tablets. Ask your doctor for advice.

Treatment with Puri-Nethol is not recommended during
pregnancy, particularly in the first three months, because it may
cause permanent damage to a foetus. If you think you could be
pregnant, or if you are planning to become pregnant, check with
your doctor before taking Puri-Nethol. You doctor will consider the
risks and benefits to you and your baby of taking Puri-Nethol.
Do not breast-feed while taking Puri-Nethol. Ask your doctor or
midwife for advice.

Puri-Nethol contain lactose

If you have been told by your doctor that you have an intolerance
to some sugars, contact your doctor before you take Puri-Nethol.

3. How to take Puri-Nethol
Puri-Nethol should only be given to you by a specialist doctor who
is experienced in treating blood problems.
Always take Puri-Nethol exactly as your doctor has told you. It is
important to take your medicine at the right times. The label on
your pack will tell you how many tablets to take and how often to
take them. If the label doesn’t say or if you are not sure, ask your
doctor, nurse or pharmacist.

You should take Puri-Nethol at least 1 hour before or 3 hours
after food or milk.

Swallow your tablets whole with a glass of water.

When you take Puri-Nethol your doctor will take regular
blood tests. This is to check the number and type of cells in
your blood and to ensure your liver is working correctly.

Your doctor may also ask for other blood and urine tests to
monitor your uric acid levels. Uric acid is a natural body
chemical, levels of which can rise while taking Puri-Nethol.

Your doctor may sometimes change your dose of Puri-Nethol
as a result of these tests.
The dose of Puri-Nethol you are given will be worked out by your
doctor based on:

your body size (surface area)

the results of your blood tests

The usual starting dose for adults and children is 2.5mg per
kilogram of your body weight each day.

Elderly patients will have their kidney and liver function
tested and if necessary the dose may need to be reduced.

Overweight children may have to take doses at the higher
end of the recommended dose range. Their doctor will
closely assess how they respond to treatment.

Children with acute lymphoblastic leukaemia may be asked
by their doctor to take Puri-Nethol in the evening as this
may lower the risk of the leukaemia getting worse again in
the future.

Patients with kidney or liver problems may need to have
their dose reduced.

If you have a condition where your body produces too little
of something called TPMT or ‘thiopurine methyltransferase’,
your dose may be reduced.
The score line is not intended for breaking the tablet.

Page 1 of 2

If you take more Puri-Nethol than you should

If you take more Puri-Nethol than you should, tell your doctor
immediately or go to a hospital straight away. Take the medicine
pack with you.

If you forget to take Puri-Nethol

Tell your doctor. Do not take a double dose to make up for a
forgotten dose.
If you have any further questions on the use of this medicine, ask
your doctor, nurse or pharmacist.

4. Possible side effects
Like all medicines, Puri-Nethol can cause side effects, although
not everybody gets them.

If you get any of the following, talk to your
specialist doctor or go to hospital straight away:

allergic reaction, the signs may include:

skin rashes

high temperature

joint pain

swollen face

any signs of fever or infection (sore throat, sore mouth or
urinary problems). Treatment with Puri-Nethol causes a
lowering of the white blood cell count. White blood cells fight
infection, and when there are too few white blood cells,
infections can occur.

any unexpected bruising or bleeding, as this could mean
that too few blood cells of a particular type are being

if you suddenly feel unwell (even with a normal

any yellowing of the whites of the eyes or skin (jaundice)

if you have diarrhoea

if you feel sick (nausea) or you are sick (vomiting).
Talk to your doctor if you have any of the following side effects
which may also happen with this medicine:

Very common (may affect more than 1 in 10

feeling or being sick (nausea or vomiting)
inflammation of the pancreas, which can give you abdominal
pain or make you sick, for patients with Inflammatory Bowel
Disease (an unlicensed use of Puri-Nethol)
liver problems – this may show up in your blood tests
yellow discolouration of your skin and/or pain under your
ribs and around the area of your stomach (biliary stasis)

mouth ulcers
inflammation of the pancreas which can give you abdominal
pain or make you sick
hair loss
severe damage to liver cells (hepatic necrosis)
allergic reaction (hypersensitivity) with:

skin rash

persistent fever

joint pain

Very rare (may affect up to 1 in 10,000 people)

lymphoma in patients with Inflammatory Bowel Disease (an
unlicensed use of Puri-Nethol) when Puri-Nethol is taken
with other drugs called anti-TNF agents.

ulcers in the intestines

in men: low sperm count

allergic reaction (hypersensitivity) with:

facial swelling
If any of the side effects gets serious, or if you notice any side
effects not listed in this leaflet, please tell your doctor or

Reporting of side effects

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

5. How to store Puri-Nethol

a drop in the number of white blood cells and platelets

Common (may affect up to 1 in 10 people)

Rare (may affect up to 1 in 1,000 people)

Keep out of the sight and reach of children.
Do not store above 25°C.
Keep the bottle tightly closed.
Do not take any tablets after the expiry date printed on the
carton and bottle label.
If your doctor tells you to stop taking the tablets, please
return any which are left over to your pharmacist for safe
disposal. Only keep them if your doctor tells you to.
If your tablets appear to be discoloured or show any other
signs of deterioration, please return to your pharmacist who
will advise you.

Uncommon (may affect up to 1 in 100 people)

loss of appetite

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6. Further information
What Puri-Nethol contains

Each tablet contains 50mg of the active ingredient
The other (inactive) ingredients are: lactose, maize starch,
hydrolysed starch, stearic acid, magnesium stearate.

What Puri-Nethol looks like and contents of the

The tablets are pale yellow, round tablets that are plain on one
side and marked on the reverse with ‘GX’ above a scoreline and
‘EX2’ underneath.
Puri-Nethol is packed in bottles of 25 tablets.


Puri-Nethol is manufactured by: EXCELLA GmbH,
Nurnberger Strasse 12, 90537 Feucht, Germany.
Procured from within the EU and repackaged by: Doncaster
Pharmaceuticals Group Ltd., Kirk Sandall, Doncaster, DN3 1QR.
Product Licence holder: BR Lewis Pharmaceuticals Ltd.,
Kirk Sandall, Doncaster, DN3 1QR.

PL No: 08929/0402

Other formats:

To listen to or request a copy of this leaflet in Braille, large print
or audio please call: 01302 365000 and ask for Regulatory
Please be ready to give the following information:
Product name Puri-Nethol 50mg Tablets
Reference number 08929/0402
Leaflet revision & issue date (ref): 11.05.15
Puri-Nethol® is a registered trademark of the Aspen Global

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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.