LEVOTHYROXINE SODIUM 100 MICROGRAMS TABLETS
Active substance(s): LEVOTHYROXINE SODIUM / LEVOTHYROXINE SODIUM / LEVOTHYROXINE SODIUM
Levothyroxine sodium 100 micrograms Tablets
Read all of this leaflet carefully before you start taking
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. Do not pass it on to
others. It may harm them, even if their symptoms are the
same as yours.
Your medicine is known as the above but will be referred to as
Levothyroxine Tablets throughout this leaflet.
Please note that this medicine is available in other strengths
which are mentioned in this leaflet.
Thyroxine is a hormone produced by the thyroid gland.
Levothyroxine is used to replace thyroxine in people whose
thyroid gland does not work properly. You will usually need to
take this medicine for the rest of your life and must not stop
taking it, or change the dose, without speaking to your doctor
This medicine can affect the way other medicines work (See
Section 2 ‘Taking other medicines’). If you take medicines to
control diabetes or warfarin to prevent blood clots, the dose
may need to be adjusted by your doctor when you start taking
You will start off taking a low dose of this medicine (See
Section 3 ‘How to take’). Your doctor will then increase the
dose gradually at 3 - 4 week intervals until your thyroxine
levels are corrected. This will help to reduce the chance of side
You will need regular blood tests whilst you are taking this
These tablets can be taken by both adults and children. If you
are giving this medicine to your child make sure you know
how many and when to give the tablets (See Section 3 ‘How
to take’) and what side effects to look out for (See Section 4
‘Possible side effects’).
In this leaflet:
1. What Levothyroxine Tablets are and what they are used for
2. Before you take Levothyroxine Tablets
3. How to take Levothyroxine Tablets
4. Possible side effects
5. How to store Levothyroxine Tablets
6. Further information
1. WHAT LEVOTHYROXINE TABLETS ARE AND WHAT
THEY ARE USED FOR
Thyroxine is a hormone which is produced naturally in the body
by the thyroid gland. Levothyroxine is a synthetic version of this
hormone. Thyroxine controls how much energy your body uses.
When the thyroid gland does not produce enough thyroxine
(a condition known as hypothyroidism), many of the body’s
functions slow down. Some of the most common symptoms of
• weight gain
• feeling depressed
Levothyroxine tablets are used to replace the thyroxine that your
thyroid gland cannot produce and prevent the symptoms of
hypothyroidism. Before starting your treatment your doctor will
carry out a blood test to work out how much levothyroxine you
2. BEFORE YOU TAKE LEVOTHYROXINE TABLETS
Do not take this medicine if you:
• are allergic to levothyroxine or to any of the other ingredients
(see section 6)
• suffer from an overactive thyroid gland that produces too
much thyroid hormone (thyrotoxicosis)
• have any condition that affects your adrenal glands (your
doctor will be able to advise you if you are not sure).
If any of these apply to you, do not take this medicine and go
back to your doctor to discuss your treatment.
Check with your doctor or pharmacist before taking
these tablets if you:
• have suffered with an under active thyroid gland for a long
• suffer from heart problems including angina, coronary artery
disease or high blood pressure
• are being treated for diabetes. The dose of your anti-diabetic
medicine may need to be changed as levothyroxine can raise
blood sugar levels
• are over 50 years of age.
Before you start taking levothyroxine your doctor will do a blood
test to see how much thyroxine your thyroid gland is making and
what dose of the medicine you will need. Once you start taking
the medicine your doctor will want you to have regular blood
tests to see how well the medicine is working.
Taking other medicines:
Many medicines affect the way levothyroxine works. The effects
of other drugs may also be affected by levothyroxine. You must
tell your doctor if you are taking or start taking any other
medicines including over the counter medicines, herbal
remedies and vitamin supplements.
The following may affect the way that levothyroxine works:
• medicines for epilepsy such as carbamazepine, phenytoin,
primidone and barbiturates
• sertraline - used to treat depression and anxiety disorders
• antacids - used to treat indigestion
• medicines containing calcium salts
• cimetidine - used to reduce excess stomach acid
• proton pump inhibitors such as omeprazole, lansoprazole
and pantoprazole - used to reduce the amount of acid
produced by the stomach
• sucralfate - used to treat and prevent stomach and duodenal
• cholestyramine and colestipol - used to treat high level of
fat in the blood
• polystyrene sulphone resin - used to reduce high levels of
potassium in the blood
• medicines containing iron that are taken by mouth
• rifampicin - used to treat infections
• imatinib - used to treat certain types of cancer
• beta blockers such as atenolol and sotalol - used to treat
high blood pressure and heart problems
• oestrogen containing medicines for hormone replacement
therapy (HRT) and contraception (the ‘pill’)
• androgen containing medicines for male hormone
• corticosteroids such as hydrocortisone and prednisolone used to treat inflammation
• amiodarone - used to treat an irregular heart beat
The following may be affected by levothyroxine:
• anticoagulant medicines to prevent blood clots such as warfarin
• medicines to treat diabetes such as insulin and metformin
• tricyclic antidepressants such as amitriptyline, imipramine
• medicines that stimulate the sympathetic nervous system
such as adrenaline (used to treat severe allergic reactions) or
phenylephrine (a decongestant found in many cold and flu
• digoxin - used to treat heart problems
• anti-inflammatory medicines such as phenylbutazone or aspirin
• propranolol - used to treat high blood pressure and heart
• ketamine - used as an anaesthetic. If you need to have an
operation, please tell your doctor or anaesthetist that you are
Pregnancy and breastfeeding:
If you are pregnant, particularly in the first three months of your
pregnancy, planning to become pregnant or are breastfeeding
tell your doctor or pharmacist before taking this medicine.
Your doctor will decide if you should continue treatment with
levothyroxine whilst you are pregnant.
Important information about some of the ingredients of
This medicine also contains lactose, a sugar. If you have been
told by your doctor that you have an intolerance to some sugars,
contact your doctor before taking this medicine.
3. HOW TO TAKE LEVOTHYROXINE TABLETS
You may be taking this medicine for the rest of your life. Always
take levothyroxine tablets exactly as your doctor has told you. If
you are not sure, check with your doctor or pharmacist.
Your dose will be decided by your doctor and will depend on
the results of your blood tests. The dose you should take will be
on the label attached by your pharmacist. Swallow the tablets
with plenty of water. You should usually take your tablets before
breakfast or your first meal of the day.
The usual starting dose is 50 - 100 micrograms every day. Your
doctor may increase the dose you take every 3 - 4 weeks by
50 micrograms until your thyroxine levels are correct. Your final
daily dose may be up to 100 - 200 micrograms daily.
Patients over 50 years of age:
The usual starting dose will be no more than 50 micrograms
every day. The dose may then be increased by 50 micrograms
every 3 - 4 weeks until your thyroxine levels are correct. Your
final daily dose will be between 50 - 200 micrograms daily.
Patients over 50 years of age with heart problems:
The starting dose will be 25 micrograms every day or 50 micrograms
every other day. The dose may be increased by 25 micrograms
every 4 weeks until your thyroxine levels are correct. Your
final daily dose will usually be between 50 - 200 micrograms daily.
Giving these tablets to children:
The dose for children depends on their age, weight and the
condition being treated. Your child will be monitored to make sure
that they get the right dose. You should give them their medicine
at least half an hour before breakfast or their first meal of the day.
If necessary, the tablets can be dissolved in 10 - 15ml of water
and given with some more liquid (5 - 10ml). The dissolved tablets
should be taken straight away. Do not keep the solution to give to
your child later.
Congenital hypothyroidism in infants:
This is a condition where your baby has been born with a thyroid
gland that does not produce enough thyroxine. The starting dose
is 10 - 15 micrograms/ kg bodyweight per day for the first three
months. The dose will then be adjusted depending on how your
baby responds to the treatment.
Acquired hypothyroidism in children:
This is a condition where your child’s thyroid gland stops working
properly because it has been attacked by their immune system,
e.g. in children with an autoimmune disease or following a viral
infection. The starting dose is 12.5 - 50 micrograms per day. The
dose will then be increased every 2 - 4 weeks depending on how
your child responds to the medicine.
This is a condition where children and adolescents develop
severe hypothyroidism (produce very low levels of thyroid
hormones). The starting dose is 25 micrograms every day. The
dose will then be increased by 25 micrograms every 2 - 4 weeks
until your child shows mild symptoms of hyperthyroidism (a
condition where the thyroid gland produces too much thyroxine).
The dose will then be reduced slightly.
If you take more Levothyroxine than you should:
If you (or someone else) swallow a lot of the tablets at the same
time, or you think a child may have swallowed some, contact
your nearest hospital casualty department or tell your doctor
immediately. Signs of an overdose may include: fever, chest pain
(angina), racing or irregular heartbeat, muscle cramps,
headache, restlessness, flushing, sweating and diarrhoea. These
signs can take up to 5 days to appear. Take any remaining tablets
and this leaflet with you so that the medical staff knows
exactly what you have taken.
If you forget to take Levothyroxine:
If you forget to take a dose take it as soon as you remember
unless it is nearly time for your next dose. Do not take a double
dose. If you forget to give your child their dose, contact your
doctor or pharmacist for further advice.
Stopping the tablets:
These tablets are for long term use. You may need to take them
for the rest of your life. Do not stop taking the tablets unless your
doctor has told you to do so.
4. POSSIBLE SIDE EFFECTS
Some people may have side-effects when taking this medicine.
Stop taking the tablets and go to hospital at once if you
• A rare allergic reaction such as swelling of the face, tongue,
lips and throat, difficulty breathing, severe itching of your skin
with raised lumps, joint pain, sensitivity to the sun, general
feeling of being unwell. You may need urgent medical attention.
Some patients may experience a severe reaction to high
levels of thyroid hormone. This is called a “thyroid crisis”
and you should contact your doctor immediately if you
have any of the following symptoms:
• very high temperature; fast heart rate; irregular heartbeat; low
blood pressure; heart failure; jaundice; confusion; fits and coma.
Tell your doctor or pharmacist if any of the following side
effects continue, get worse or if you notice any other side
effects not listed.
Most of the side effects are similar to the symptoms of
hyperthyroidism (where the thyroid gland makes too much
thyroxine) and are due to your dose of the medicine being too
high. They will usually disappear after reducing the dose or
stopping the tablets. However, you must not change the dose
or stop the tablets without talking to your doctor first.
• high temperature, sweating
• weight loss
• tremor, restlessness, excitability, difficulty sleeping (insomnia)
• increased pressure around the brain in children that is not
caused by a tumour or other diseases (benign intracranial
• chest pain (angina), pounding, irregular or fast heartbeat
• diarrhoea, vomiting
• muscle cramps, muscle weakness
• deformity of the skull in infants caused by the early closure of
joins in the skull bone (craniostenosis)
• growth in children may slow or stop due to changes in bone
• irregular periods
• intolerance to heat
• temporary hair loss in children.
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 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 LEVOTHYROXINE TABLETS
Do not store above 25oC. Store in the original package in order
to protect from light and moisture.
Do not use Levothyroxine tablets after the expiry date which is
stated on the box. The expiry date refers to the last day of that
Keep out of the sight and reach of children.
If your tablets become discoloured or show any sign of
deterioration, return them to your pharmacist.
Medicines should not be disposed of via wastewater or
household waste. Ask your pharmacist how to dispose of
medicines no longer required. These measures will help protect
6. FURTHER INFORMATION
What Levothyroxine Tablets contain:
Each tablet contains 100 micrograms of levothyroxine sodium.
The tablets also contain sodium citrate, lactose monohydrate,
maize starch, acacia powder and magnesium stearate.
What Levothyroxine Tablets look like and contents of the
White, uncoated, biconvex, round tablets, with the words
‘Eltroxin 100’ engraved on one side and with a breakline on the
Levothyroxine sodium 100 micrograms Tablets are available in
blister packs of 28 tablets.
Custom Pharmaceuticals Ltd., Tecore House, Conway Street,
Hove, East Sussex, BN3 3LW, UK
Procured from within the EU and repackaged by the
Product Licence Holder: Summer Healthcare Ltd., 4 Petre Road,
Clayton Business Park, Clayton-Le-Moors, Accrington BB5 5JB,
Levothyroxine sodium 100 micrograms tablets PL: 33948/0047
Date of Leaflet: 13th September 2016
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.