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Metformin Hydrochloride Tablets 500mg (Metformin Hydrochloride)
Please read this entire 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.

If any of the side effects get serious or you notice any not listed in this leaflet, please tell your doctor
or pharmacist.
The name of this medicine is Metformin Hydrochloride Tablets 500mg (also referred to as Metformin
Hydrochloride throughout this leaflet).

In this leaflet:
1 What this medicine is and what it is used for
2 Before you take
3 How to take
4 Possible side effects
5 How to store
6 Further information


What this medicine is and what it
is used for

Metformin Hydrochloride Tablets 500mg belong to a group
of medicines called biguanide oral anti−hyperglycaemic
agents. It works by lowering your blood−sugar level.
Metformin Hydrochloride is used to treat non−insulin
dependent diabetes when a change of diet has failed to
reduce blood sugar levels, particularly if overweight.
It may be used alone as initial therapy or along with another
group of medicines called sulphonylureas, which stimulate
the pancreas to produce more insulin.
Sometimes Metformin Hydrochloride is also used to treat
patients suffering from insulin dependent diabetes, who are
over weight (obese) and whose symptoms are poorly
If your blood sugar levels are not controlled, it can lead to
serious problems such as kidney damage, amputations and
blindness. Metformin Hydrochloride is thought to work by
decreasing the amount of sugar absorbed from food
through the stomach, by helping the body respond better to
the insulin it makes naturally and by decreasing the amount
of sugar produced by the liver and kidneys.


Before you take

Do not take Metformin Hydrochloride Tablets 500mg if:

you are allergic to Metformin Hydrochloride or any of
the other ingredients.

you have any kind of kidney or liver disease.

you have serious diabetic complications such as loss
of consciousness caused by either very high or very
low blood sugar levels ( diabetic coma) and a lack of
insulin which leads to high blood sugar levels, ketones
in the urine and certain acids in the blood

you have heart complications such as heart failure
(even if the condition is under control) or recently had
a heart attack.

you have a history of a build up of lactic acid in the
blood (lactic acidosis), which may be associated with
shock and breathing difficulties.

you regularly consume excess alcohol.

you have a severe infection or injury.

you suffer from a loss or lack of water in the body

you have a severe disease of the blood vessels.
If any of the above apply to you, please consult your
doctor or pharmacist.

Take special care with Metformin Hydrochloride:
If you are to undergo diagnostic tests (using iodinated
contrast media) ˘ you should tell your doctor as you
may need to stop your medication.

if you continuously use Metformin Hydrochloride. It
may reduce your vitamin B12 level and should be
annually monitored by your doctor.

if you suffer from kidney problems, particularly if elderly.
If any of the above apply to you, please consult your
doctor or pharmacist.

Taking other medicines
Please inform your doctor or pharmacist if you are taking or
have recently taken any other medicines, including
medicines obtained without prescription.
Other medicines may interfere with the actions of Metformin
Hydrochloride. You should tell your doctor if you are taking
any of the following:

cimetidine, for stomach ulcers and indigestion.

medicines to prevent clotting of the blood, such as
warfarin (anticoagulants).

medicines for high blood pressure, such as captopril
(ACE inhibitors).

medicines for depression, such as moclobemide
(MAO inhibitors).

diazoxide, for high blood pressure.

medicines for lowering high blood pressure, such as
propanolol (beta−blockers).

medicines for inflammatory and allergic conditions,
such as beclometasone (corticosteroids).

oral contraceptives.

medicines for fluid retention, such as bumetanide

medicines for high cholesterol, such as ezetimibe

medicines for diabetes such as glibenclamide
(sulphonylureas) or insulin.
Taking with alcohol
If you drink alcohol whilst taking Metformin Hydrochloride it
may interfere with the actions of the medicine.
Pregnancy and breast−feeding
If you are pregnant, thinking of becoming pregnant or
breast−feeding, Metformin Hydrochloride should not be
taken unless told to do so by your doctor.
Driving or using machinery
Metformin Hydrochloride should not affect your ability to
drive or operate machinery.
Important information about some of the ingredients
This medicine contains lactose. If you have been told by
your doctor that you have intolerance to some sugars,
contact your doctor before taking this product.


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How to take

You should always take this medicine as prescribed by
your doctor. Do not take more than the doctor has told you
to. Read and follow the instructions on the pharmacist’s
label. If you are not sure about anything, please ask your
doctor or pharmacist.

These tablets are for oral administration.
Metformin Hydrochloride Tablets 500mg should be
taken with or after food.

Keep out of the reach and sight of children.
Store in the original package.
Do not take after the expiry date, which is stated on the
carton after EXP. The expiry date refers to the last day of
that month.
If your doctor tells you to stop taking your medicine, you
should return any remaining tablets to the pharmacist,
unless your doctor tells you to keep them.

The doses stated below are guidelines only. You should
always take this medicine as prescribed by your doctor.
The usual dose is one 500mg tablet three times a day. This
medicine may take a few days to 2 weeks to control your
condition. Your doctor may increase the dosage to a
maximum of 3000mg per day until your condition is under
Your doctor will monitor your condition if you have kidney
Metformin Hydrochloride Tablets 500mg are not
recommended for children.

If you have taken more Metformin Hydrochloride than
you should
Contact your doctor immediately or go to the nearest
accident and emergency department. Remember to take
this leaflet or any remaining tablets with you.



Possible side effects

Metformin Hydrochloride is usually well tolerated. However,
like most medicines it can cause unwanted side effects in
some patients.
Serious side effect:
There are only a few reported cases but some people have
developed a condition known as lactic acidosis whilst taking
Metformin Hydrochloride.
Lactic acidosis is caused by a build up of lactic acid in the
blood (produced when glucose is turned into energy without
Possible symptoms of lactic acidosis:
unexplained weight loss
feeling sick (nausea)
being sick (vomiting)
general feeling of being unwell
pain in the belly region
increased breathing rate
If you have or think you may have lactic acidosis, you
should go to the hospital immediately as it is a medical

Further information

What Metformin Hydrochloride Tablets 500mg contain:
The active ingredient is: Metformin Hydrochloride
 Other ingredients are: microcrystalline cellulose,
sodium starch gylcollate, povidone k−28, colloidal
anhydrous silica and magnesium stearate.
 Film coating is: opadry white OY−L−28900 consisting
of lactose monohydrate, hypromellose, titanium dioxide
(E171) and macrogol 4000.

If you forget to take Metformin Hydrochloride
Take as soon as you remember. Do not take a double dose
to make up for the forgotten individual dose.

How to store

This medicine contains lactose (see important
information about some of the ingredients at the end
of section 2)

What Metformin Hydrochloride Tablets 500mg look like
and the contents of the pack:
Metformin Hydrochloride Tablets 500mg are white, oblong,
film−coated tablets with a score notch on one side and
marked M500 on the other.
They are available in packs of 28, 30, 56, 84 and 120
tablets. Not all pack sizes may be marketed
This medicine is only for YOU. Do not offer it to anybody
else. It may harm them even if their symptoms seem to be
the same as yours.
This information applies only to Metformin Hydrochloride
Tablets 500mg.
Marketing Authorisation Holder and Manufacturer:
Tillomed Laboratories Ltd
3 Howard Road.
Eaton Socon, St Neots
PE19 8ET
United Kingdom.

Product Licence Number:
Metformin Hydrochloride Tablets 500mg:
PL 11311/0466

Date of revision: October 2009

Side effects (usually short−term)
 feeling sick (nausea)
 being sick (vomiting)
 weight loss
These side effects may be avoided by taking your medicine
with or after food.
If you have any of these side effects important to
continue taking your medicine as they normally
disappear after a short time.
Other side effect
decreased vitamin B12 absorption

If any of these side effects get serious or you notice any
not listed, please tell your doctor or pharmacist.

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0800 970 6115

for help
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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.