Skip to Content

UK Edition. Click here for US version.

METFORMIN HYDROCHLORIDE 500MG TABLETS

Active substance(s): METFORMIN HYDROCHLORIDE

View full screen / Print PDF » Download PDF ⇩
Transcript
PATIENT INFORMATION LEAFLET

Metformin Hydrochloride 500mg Tablets
(Metformin Hydrochloride)
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 your 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.

In this leaflet:
1
2
3

1

What Metformin is and what it is used for
What you need to know before you take
Metformin
How to take Metformin

What Metformin is and what it
is used for

Metformin (also referred to as Metformin
Hydrochloride throughout this leaflet) is an anti−
diabetic drug which belongs to a group of
medicines called biguanides. It works by lowering
your blood−sugar level.
If your blood sugar levels are not controlled, it
can lead to serious problems such as kidney
damage, amputations and blindness. Metformin
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.

4
5
6





Sometimes Metformin Tablets are also used to
treat patients suffering from insulin dependent
diabetes, who are overweight (obese) and whose
symptoms are poorly controlled.

2

What you need to know before
you take Metformin

Do not take Metformin Tablets if:












you are allergic to metformin hydrochloride
or any of the other ingredients of this
medicine (listed in section 6 ‘Contents of the
pack and other information‘).
you have very high blood sugar levels
(hyperglycaemia) or ketoacidosis, which can
lead to diabetic pre−coma. Diabetic
ketoacidosis is a condition in which
substances called ’ketone bodies’
accumulate in the blood, due to consistently
high blood glucose levels. Symptoms
include stomach pain, fast and deep
breathing, sleepiness or unusual fruity odour
of the breath.
you have kidney or liver disease.
you have heart failure or have recently had
a heart attack, have severe problems with
your circulation (such as shock) or have
breathing difficulties. This may lead to a lack
in oxygen supply to tissue which can put
you at risk for lactic acidosis (see ’Warnings
and precautions’ below).
you suffer from alcoholism.
you suffer from a loss or lack of water in the
body (dehydration), such as due to long−
lasting or severe diarrhoea, or if you have
vomited several times in a row. Dehydration
may lead to kidney problems, which can put
you at risk for lactic acidosis (see ’Warnings
and precautions’ below).
you have a severe infection, such as an
infection affecting your lung or bronchial
system or your kidney. Severe infections
may lead to kidney problems, which can put
you at risk for lactic acidosis (see ’Warnings
and precautions’ below).

Warnings and precautions
Talk to your doctor before taking Metformin:





if you have diabetes and kidney problems
as you are more at risk of developing a rare
but serious side effect known as ’lactic
acidosis’. The risk of lactic acidosis is also
increased with uncontrolled diabetes, an
increased level of ketones in your blood
(ketosis), prolonged fasting, drinking an
excessive amount of alcohol or liver
problems. Symptoms of lactic acidosis are
vomiting, bellyache (abdominal pain) with
muscle cramps, a general feeling of not
being well with severe tiredness, and
difficulty in breathing (see section 4
’Possible side effects’).
If this happens to you, you may need
immediate hospital treatment, as lactic
acidosis may lead to coma. Stop taking
Metformin immediately and contact a
doctor or the nearest hospital straight
away.
if you have kidney problems, particularly if
you are elderly.
if you continuously use Metformin. It may

reduce your vitamin B12 level and should
be annually monitored by your doctor.
if you are taking Metformin together with
other medicines used to treat diabetes,
such as insulin, sulphonylureas or
meglitinides.
if you are to undergo diagnostic tests (using
iodinated contrast media) or you need to
have major surgery, you must tell your
doctor. You will need to stop taking
Metformin Hydrochloride for a certain period
of time before and after the diagnostic tests
or surgery.

Monitoring kidney function and diabetes


Metformin is used to treat non−insulin dependent
diabetes (also called type 2 diabetes) when an
improvement in diet and exercise has failed to
reduce blood sugar levels, particularly if
overweight.
It may be used alone as initial therapy or along
with other oral antidiabetic drugs or with insulin.
Children 10 years and over and adolescents can
take Metformin on its own or together with insulin.

Possible side effects
How to store Metformin
Contents of the pack and other
information



Kidney function: As Metformin is excreted
by the kidney your doctor will test your
kidney function. This should be done before
starting treatment and regularly thereafter:
once a year for normal kidney function and
two to four times a year if you have kidney
problems or you are elderly
Diabetes: Usual laboratory tests for
diabetes monitoring should be performed
regularly

Other medicines and Metformin
Tell your doctor or pharmacist if you are taking or
have recently taken or might take any other
medicines, including medicines obtained without
prescription.
If you are to undergo diagnostic tests (using
iodinated contrast media) or you need to have
major surgery, you must tell your doctor. You will
need to stop taking Metformin Hydrochloride for a
certain period of time before and after the
diagnostic tests or surgery (see ’Warnings and
precautions’ above)
Other medicines may interfere with the actions of
your Metformin Tablets. You should tell your
doctor if you are taking any of the following
medicines and Metformin at the same time. You
may need more frequent blood glucose tests or
your doctor may adjust the dosage of Metformin:






other medicines used to treat diabetes such
as glibenclamide (known as
sulphonylureas), meglitinides or insulin.
medicines called ’diuretics’ that are used to
treat fluid retention or high blood pressure
such as furosemide
medicines to thin the blood such as warfarin
(anticoagulants).
cimetidine, for stomach ulcers and
indigestion.
medicines for inflammation and allergic
reactions, such as betamethasone
(glucocortcoids).

Metformin and alcohol
You should not drink alcohol whilst taking
Metformin Hydrochloride. Alcohol may increase
the risk of lactic acidosis especially if you have
liver problems, you are undernourished or you
are fasting. This also applies to medicines that
contain alcohol.
Pregnancy and breast−feeding
If you are pregnant or breast−feeding, think you
may be pregnant or are planning to have a baby,
ask your doctor for advice before taking this
medicine.
Pregnancy
If you are pregnant or you are planning to
become pregnant you should not take Metformin.
However, your diabetes needs to be controlled
during pregnancy and this should be done by
taking insulin.
Breast−feeding
You should not take Metformin whilst breast−
feeding unless your doctor thinks the benefits
outweigh the risks.
Ask your doctor or pharmacist for advice before
taking any medicine.
Driving or operating machines
If you are taking Metformin on its own it should
not affect your ability to drive or operate
machinery.
However, if you are taking Metformin together
with other medicines to treat diabetes (such as
sulphonylureas, insulin or meglitinides) it may
cause hypoglycaemia (low blood glucose level).
Symptoms of hypoglycaemia include weakness,
dizziness, increased sweating, fast heart beat,
continued....

Hard to Read?

Phone

0800 970 6115

for help
Till−Ipc−V.1s

vision disorders or difficulty in concentrating. If
you have any of these symptoms do not drive or
use machinery.

3

How to take Metformin

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

Metformin Tablets are for oral use only

Recommended to be taken with or after
meals
The recommended dose is:
Adults
The usual starting dose is 500mg or 850mg, 2 or
3 times a day.
The maximum dose is 3000mg a day taken as 3
divided doses.
After taking Metformin for 10 to 15 days the
doctor will adjust the dose based on blood sugar
measurements.
Older patients and patients with kidney
problems
Your doctor will choose the correct dosage
depending on the seriousness of your kidney
problem, and will need to have regular checkups
to monitor your kidney function.
Use in children (10 years and above) and
adolescents:
The normal dose is 500mg or 850mg, once a day.
The maximum dose is 2000mg a day taken as 2
or 3 divided doses.
After taking Metformin for 10 to 15 days the
doctor will adjust the dose based on blood sugar
measurements.
Treatment of children between 10 and 12 years of
age is only recommended on specific advice from
your doctor, as experience in this age group is
limited.
If you take insulin too, your doctor will tell you
how to start Metformin.
If you have taken more Metformin than you
should
If you accidentally take too many tablets, consult
your doctor or the nearest hospital casualty
department immediately. Take this leaflet or
some tablets with you so that people will know
what you have taken.
An overdose of Metformin may lead to lactic
acidosis (for symptoms see Section 4 ’Possible
side effects’)
If you forget to take Metformin
Take it as soon as you remember, unless it is
time for your next dose. 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 or pharmacist.

4

Possible side effects

Serious side effect
Although very rare, some people have developed
a condition known as lactic acidosis whilst taking
Metformin Tablets. Although lactic acidosis is a
serious condition, it is not normally a problem with
metformin, provided it is correctly treated.
Lactic acidosis is caused by a build up of lactic
acid in the blood (produced when glucose is
turned into energy without oxygen).

skin or whites of the eyes
There are only isolated reports of abnormal liver
function or hepatitis and these have been
resolved when treatment was stopped. If this
happens to you, stop taking Metformin and talk to
your doctor
Children and adolescents
Limited data in children and adolescents showed
that adverse events were similar in nature and
severity to those reported in adults.
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 internet at
(www.mhra.gov.uk/yellowcard). By reporting side
effects you can help provide more information on
the safety of this medicine.

5

How to store Metformin

Keep this medicine out of the sight and reach
of children.
Store below 25°C, store in the original package in
order to protect from light.
Do not use this medicine after the expiry date
which is stated on the carton/blister after EXP.
The expiry date refers to the last day of that
month.
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.

6

Contents of the pack and
other information

What Metformin Tablets contain:

The active substance is Metformin
Hydrochloride.
Each tablet contains 500mg of Metformin
Hydrochloride.

The other ingredients are: povidone K30,
microcrystalline cellulose, colloidal
anhydrous silica, magnesium stearate,
sodium starch glycollate, ethyl cellulose 7
cps, hypromellose, propylene glycol and
titanium dioxide (E171).
What Metformin Tablets look like and the
contents of the pack:
Metformin Tablets approximately 12mm, white,
round, convex, film−coated tablets marked 17
LG on the one side.
They are available in pack sizes of 28, 50, 56,
84, 100 and 500 tablets.
Not all pack sizes may be marketed.
REMEMBER
This medicine is only for YOU. Only a doctor can
prescribe it, so never offer it to anybody else. It
may harm them, even if their symptoms seem to
be the same as yours.
Marketing Authorisation Holder &
Manufacturer
Tillomed Laboratories Ltd
3 Howard Road,
Eaton Socon, St Neots
Cambridgeshire PE19 8ET, UK
Product Licence Number:
PL 11311/0196: Metformin Hydrochloride
500mg Tablets
Date of approval May 2014

Possible symptoms of lactic acidosis:

unexplained weight loss

feeling sick (nausea)

being sick (vomiting)

general feeling of being unwell

pain in the belly region

difficulty breathing

muscle cramp

severe weakness or loss of strength

feeling cold
If you have or think you may have lactic
acidosis, you should go to the hospital
immediately as it is a medical emergency.
Very common side effects (may affect more
than 1 in 10 people)

feeling sick (nausea)

being sick (vomiting)

diarrhoea

abdominal pain

loss of appetite
These side effects usually occur at the start of
treatment. You should continue to take your
medicine as they normally disappear after a short
time. They may be avoided by taking your
medicine with or after food and in 2 or 3 divided
doses.
Common side effects (may affect up to 1 in 10
people)

change in taste
Very rare side effects (may affect up to 1 in
10,000 people)
 skin reactions such as flushing of the skin,
itching or itchy rash
 decreased vitamin B12 absorption
 abnormal liver function test (detected through
blood test) or inflammation of the liver
(hepatitis), which may cause tiredness, loss
of appetite, weight loss or yellowing of the

Hard to Read?
Product Name
Strength / Form
Type
Dimensions
Typefaces
Rev #
Last updated
No. of Colours

Phone

Metformin PIL
500mg Tablets
PIL
150 x 480 mm
Font SansSerif − Min. Text 8pt
Till−Ipc−V.1s
10/06/2014
Pantone Black CVC

0800 970 6115

for help
Till−Ipc−V.1s

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.

Hide