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Active substance(s): TOLBUTAMIDE

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Please read all of this leaflet carefully before you start taking this medicine.
• Keep this leaflet. You may need to read it again.
• If you have further questions, please ask your doctor or your pharmacist.
• This medicine has been prescribed for you personally and you should not pass it on to
others. It may harm them, even if their symptoms are the same as yours.
1. What your medicine is and what it is used for
2. Before you take your medicine
3. How to take your medicine
4. Possible side effects
5. Storing your medicine
6. More information



Tolbutamide 500mg Tablets is a medicine used to
reduce blood sugar levels. It is one of a group of
medicines called oral hypoglycaemics, which
control blood sugar levels in some types of
diabetes (type 2 diabetes mellitus). Tolbutamide is
used to treat diabetes of the non-insulin
dependent type, which does not respond to
dietary measures. This generally only occurs in
adults. It lowers the sugar content in your blood if
this is too high.



Do not take Tolbutamide 500mg Tablets if you:
• have ever had an allergic reaction to
tolbutamide or any of the ingredients in
the tablet. An allergic reaction may include a
rash, itching, difficulty breathing or swelling of
the face, lips, throat or tongue
• have diabetes that needs to be treated by
insulin (type 1 or insulin dependent diabetes)
• have ever had a severe diabetic reaction such
as “acidosis” (a complication of diabetes with
rapid weight loss, nausea or vomiting) or
diabetic coma
• have severe kidney, liver, thyroid or adrenal
gland disease
• are particularly stressed
• are breast-feeding
• suffer from a condition called porphyria (a
hereditary disease affecting the liver or bone
If you need to have an operation, tell your doctor
you are taking Tolbutamide.
Take special care with Tolbutamide 500mg
This medication should be taken as part of a
treatment plan, which includes diet, physical
exercise and, where necessary, weight reduction.
During Tolbutamide treatment regular monitoring
of your blood sugar is necessary. Your doctor may
also take blood tests to monitor your blood cell
levels and liver function.
If your treatment plan is not correct you may
suffer from the following conditions:
Low blood sugar (hypoglycaemia)
symptoms include: sweating, paleness,
headache, faintness or drowsiness
High blood sugar (hyperglycaemia):
symptoms include: thirst, frequent urination, dry
mouth, dry itching skin, fungal or skin infections
Please inform your doctor if you experience any
of these symptoms so that your dose can be
Alcohol can enhance or diminish the ability of
your medicine to reduce blood sugar in an
unpredictable manner. You are advised NOT to
drink alcohol with this medicine.
Pregnancy and breast-feeding
This medication should not be taken during
pregnancy. If pregnancy is planned you should
discuss the treatment plan with your doctor. If you
become pregnant during your treatment you
should inform your doctor immediately.
Do not take Tolbutamide 500mg Tablets if you are

• Change from other tablets - You can usually
change between different diabetes tablets
without a break in treatment. Initially two tablets
daily. The maintenance dose will depend upon
your response to treatment.
• Change from insulin - Low insulin doses
(less than 20 units) can be replaced
immediately. With high insulin doses a gradual
change is required. Insulin and tolbutamide
will be given together and the insulin dose will
be gradually reduced.
If you do not achieve adequate control of your
diabetes through diet and 4 tablets of
Tolbutamide daily then your doctor may also give
you another drug, such as metformin, to help you
control your blood sugar levels.

Driving and using machines
Your ability to concentrate or react may be
impaired if your blood sugar is lowered
(hypoglycaemia), or raised (hyperglycaemia) or if
you develop visual problems as a result of such
conditions. Make sure your abilities are not
affected before you drive or operate machinery.
Taking other medicines
The activity and safety of this treatment may be
affected if this medicine is taken at the same time
as certain other medicines. Conversely, other
medicines may be affected if they are taken at the
same time as this medicine. Consult your doctor
before you start taking another medicinal product
even those you obtain without prescription.
The blood sugar lowering effects of your medicine
may be strengthened and signs of low blood
sugar levels may occur when one of the following
drugs is taken:
• medicines to treat high blood pressure such as
beta blockers (e.g. propranolol, atenolol),
ACE inhibitors (e.g. captopril) and fibrates
(e.g. clofibrate)
• adrenaline (epinephrine)
• allopurinol and sulfinpyrazone (used in the
treatment of gout)
• antibiotics used to treat infections, such as
chloramphenicol, rifampicin, flouroquinolones,
tetracyclines or sulphonamides such as
sulphafurazole and co-trimoxazole
• certain antifungal medicines (e.g. fluconazole)
• cimetidine and ranitidine (used for stomach
• medicines used to prevent blood clotting
(e.g. warfarin, heparin or dicoumarol)
• medicines used to treat depression such as
monoamine oxidase inhibitors (MAOIs) and
tricyclic antidepressants
• medicines used to treat mental health
problems, such as lithium
• corticosteroids (strong anti-inflammatory
• cyclophosphamide (used to treat some
• phenylbutazone (a non-steroidal
anti-inflammatory pain killer)
• diuretics (water tablets) such as
bendroflumethiazide, hydrochlorothiazide
• the contraceptive pill
• salicylates (used for muscular or skeletal
• octreotide (used to treat certain tumours)
• some herbal medicines such as St John’s wort
and Ginkgo biloba
Please tell your doctor or pharmacist if you are
taking or have recently taken any other
medicines, even those not prescribed.



The dose is fixed by the doctor, depending on
your blood and urine sugar levels. Changes in
external factors (e.g. weight reduction, change in
life style, stress) or improvements in the disease
may require changed tolbutamide doses.
Your doctor has carefully chosen the correct
dosage for you and for that reason you should
always take the dose of medicine prescribed for
you. The pharmacist's label on the carton will tell
you when to take your tablets. The usual doses
are given below.
• Untreated diabetes - Initially two tablets daily.
The maintenance dose will depend upon your
response to treatment, the usual daily dose is
1-3 tablets daily.

If you are run down or elderly or suffer from
kidney problems, you will be advised specifically
on how many and how often to take the tablets.
These tablets are generally not suitable for
children, as children usually have
insulin-dependent (type 1) diabetes, which should
not be treated with tolbutamide.
Unless your doctor has told you differently,
swallow these tablets with or immediately after
the first main meal of the day or in smaller doses
throughout the day with meals. Take this medicine
for as long as your doctor tells you to.
If you take more Tolbutamide 500mg Tablets
than you should
Call a doctor straight away or go immediately to
the nearest hospital casualty department, taking
the remaining tablets with you. There is a danger
of low sugar levels (symptoms may include
sweating, paleness, headache, faintness or
drowsiness) and therefore you should instantly
consume sugar (e.g. sugar cubes, sweet juice,
sweetened tea). Persons in a state of
unconsciousness must not be given food or drink.
If you forget to take Tolbutamide 500mg
If you forget to take a dose, take your next dose
as soon as you remember, unless it is nearly time
to take the next one. NEVER take two doses
together. Take the remaining doses at the correct



Do not use after the expiry date that is stated on
the outer packaging.
Do not store above 25°C. Store in the original
container or package.
Medicines should not be disposed of via waste
water or household waste. Ask your pharmacist
how to dispose of medicines no longer required.
These measures will help to protect the



Tolbutamide 500mg Tablets are white, biconvex
tablets with a breakline containing 500mg
tolbutamide. Each tablet is marked with the
characters “T” and “500". The other ingredients
are maize starch, magnesium stearate, stearic
acid, povidone (K90) and sodium starch
Pots are available in pack sizes of 28, 50, 100 &
500 tablets.
Blister pack is available in a pack size of 28
Not all pack sizes or pack types may be
Marketing Authorisation Holder
Kent Pharmaceuticals Limited,
Repton Road, Measham, DE12 7DT, U.K.
Manufacturer responsible for batch release
Kent Pharmaceuticals Limited,
Crowbridge Road, Ashford, Kent TN24 0GR, U.K.
Kent Pharmaceuticals Limited,
Repton Road, Measham, DE12 7DT, U.K.
Kent Pharmaceuticals Limited,
Repton Road, Measham, DE12 7DT, U.K.
PL 08215/0007
This leaflet was revised April 2014.

Effects when treatment with Tolbutamide
500mg Tablets is stopped
If you interrupt or stop the treatment you should
be aware that the desired blood sugar lowering
effect will not be achieved and you may
experience hyperglycaemia. If any change is
necessary it is important for you to contact your
doctor first.



Like all medicines, Tolbutamide 500mg Tablets
can cause side effects, although not everybody
gets them. Most side effects are dose-dependent
and disappear when the dose is reduced or if the
medicine is no longer taken. Side effects occur
most often at the start of treatment. Side effects
are generally mild and temporary.
If you experience any of the following events
you should tell your doctor immediately, as
your medication may need to be discontinued.
Very Rare
• Itchy skin, rash and hives
• Swelling of the face, lips, tongue or throat or
difficulty breathing or swallowing
• Your skin or eyes appear yellow
The following events are less serious but you
may wish to discuss them with your doctor or
pharmacist if they become troublesome or
last a long time.
Very Rare
• Sensitivity to light, skin rashes
• Anaemia
• Low blood sugar
• Headache, tingling sensation
• Ringing in the ear
• Nausea, vomiting, diarrhoea, constipation,
increased or decreased appetite or weight gain
• An intolerance to alcohol
Tolbutamide may change the number and type of
cells in the blood, if you notice an increase in
bruising or nose bleeds or in the number of sore
throats or infections you are getting, tell your
doctor. If you notice any side effects not
mentioned in this leaflet, please inform your
doctor or pharmacist.


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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.