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Package leaflet: Information for the user
Levothyroxine 25 Micrograms Tablets
Levothyroxine Sodium
Read all of this leaflet carefully before
you start using this medicine because it
contains important information for you.
- Keep this leaflet. You may need to read
it again.
- If you have further questions, please ask
your doctor or 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.
The name of your medicine is Levothyroxine 25 Micrograms Tablets.
In the rest of this leaflet it is called Levothyroxine Tablets.
What is in this leaflet:
1. What Levothyroxine Tablets are and what they are used for
2. What you need to know before you take Levothyroxine Tablets
3. How to take Levothyroxine Tablets
4. Possible side effects
5. How to store Levothyroxine Tablets
6. Contents of the pack and other information

1. What Levothyroxine Tablets are and what
they are used for
The active ingredient in Levothyroxine Tablets is levothyroxine sodium
which is the same as thyroxine, a hormone produced by the thyroid gland.
Levothyroxine Tablets are used in the treatment of an underactive
thyroid gland since they replace the thyroxine that would normally be
produced naturally by the thyroid gland.

2. What you need to know before you take
Levothyroxine Tablets
Do not take Levothyroxine Tablets if you:
• are allergic to levothyroxine sodium or any of the other ingredients
of this medicine (listed in section 6)
• have an overactive thyroid gland
• have any condition that affects your adrenal gland (your doctor will
advise you if you are not sure).
If any of the above statements apply to you, you should not take
Levothyroxine Tablets.
Warnings and precautions
Talk to your doctor before taking Levothyroxine Tablets if you:
• have had an underactive thyroid gland for a long time
• have heart problems, such as angina, heart failure, coronary artery
disease or you have had a previous heart attack
• have high blood pressure
• suffer from diabetes. The dosage of your diabetic treatment may
need to be altered
• have an underactive pituitary gland (a gland in your brain)
• have an underactive adrenal gland (a gland located near your
kidneys). You may need to have steroid therapy as well
• are over 50 years of age.
Blood tests
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.
Other medicines and Levothyroxine Tablets
Taking another medicine while you are taking Levothyroxine Tablets
can affect how it or the other medicine works. Tell your doctor or
pharmacist if you are taking, have recently taken or might take any
other medicines or herbal products, including those you may have
bought yourself without a prescription.

Please check with your doctor if you are taking any of the following (or
any other medication):
• Anticoagulants, such as warfarin (or another coumarin), or
pheninidone, which are used to thin the blood
• Anticancer agents, such as Imatinib
• Anticonvulsants, such as carbamazepine, phenobarbital, phenytoin
or primidone which are used to treat epilepsy and barbiturates
• Colestyramine or colestipol, a drug used to lower cholesterol in the
• Drugs which act like adrenaline, such as salbutamol, salmeterol,
terbutaline or ephedrine, which are used in the treatment of asthma
or certain circulation problems
• Antacids containing calcium carbonate, or a combination of
aluminium and magnesium, taken for indigestion
• Rifampicin, an antibiotic, used to treat infections
• Antidepressants, such as amitriptyline or sertraline, used to treat
• Treatments for diabetes, such as insulin injections, or tablets such
as gliclazide or glibenclamide
• Beta-blockers, such as propanolol, atenolol, sotalol or labetolol,
used to treat heart conditions or high blood pressure
• Ketamine, a general anaesthetic
• Iron tablets, such as ferrous sulphate, used to treat anaemia
• Steroids and sex hormones, such as oestrogens, used for
contraception and HRT or androgens, used to treat male hormone
deficiency in men and breast cancer in women
• Sucralfate or cimetidine, used to treat stomach ulcers
• Polystyrene sulphonate resins, used to treat high levels of
potassium in the blood
• Cardiac glycosides, such as digoxin or digitoxin, used in the
treatment of heart failure
• Weight loss drugs, such as Orlistat
• Anti-inflammatory drugs e.g. phenylbutazone and aspirin
• Amiodarone, used to treat an irregular heart beat
• Proton-pump inhibitors such as omeprazole, lansoprazole and
pantoprazole, used to reduce the amount of acid produced by the
If you have any doubts about whether you should take this medicine
then discuss matters with your doctor before taking it.
Pregnancy and breast-feeding
You should let your doctor know if you are pregnant or trying to
become pregnant whilst taking this medicine.
You should speak to your doctor if you are breast-feeding or wish to
begin breast-feeding whilst taking Levothyroxine Tablets.
Levothyroxine Tablets contain lactose and sucrose
If you have been told by your doctor that you have an intolerance to
some sugars, contact your doctor before taking this medicinal product,
as it contains lactose and sucrose. You should not take Levothyroxine
Tablets if you have hereditary problems such as galactose intolerance,
the Lapp lactose deficiency or glucose-galactose malabsorption.

3. How to take Levothyroxine Tablets
Always take this medicine exactly as your doctor or pharmacist has
told you. Check with your doctor or pharmacist if you are not sure.
Unless instructed differently, take your tablets with a glass of water,
preferably before breakfast.
Adults and children twelve years of age and over Starting dose
The usual starting dose for adults is 50 to 100 micrograms daily. This
can be increased by 25 to 50 micrograms at intervals of two to four
weeks, as required.
Maintenance dose
The usual maintenance dose is 100 to 200 micrograms daily as a
single dose.
Elderly patients or patients with heart problems
If you are elderly or have heart problems, your doctor will start you on
a low dose of Levothyroxine Tablets (25 to 50 micrograms daily) and
gradually increase this by 25 to 50 micrograms daily at two to four
week intervals, until your thyroid levels are normal.
Children under 12 years:
The dose for children depends on their age, weight and the condition
being treated. Your child will be monitored to make sure he/she gets
the right dose. Give your child this medicine at least half an hour
before the first meal of the day.

Congenital hypothyroidism in infants:
Initially 10 to 15 micrograms/kg body weight a day for the first three
months. The dose will then be adjusted depending on response to

Acquired hypothyroidism in children:
Initially 12.5 to 50 micrograms a day. The dose should be increased
gradually every two to four weeks depending on response to treatment.

Infants and children
Infants and children given levothyroxine
may have problems with bone growth
and, rarely, temporary hair loss or raised
pressure inside the skull causing
headache and eye problems.

You should have regular check-ups, including blood tests, to make
sure the dose is right for you.
If you take more Levothyroxine Tablets than you should
If you accidentally take too many tablets contact your doctor,
pharmacist or nearest hospital casualty department. Take this leaflet
and any remaining tablets with you to show the doctor or pharmacist.
Signs that you have taken too many tablets include palpitations, a
rapid heart rate, an irregular heart beat, raised blood pressure, angina
(chest pain), tremor, difficulty sleeping and abnormally high body
temperature, sensitivity to heat, sweating, headache, restlessness,
confusion, anxiety, weight loss, diarrhoea, vomiting and irregular
periods. Fits, coma and death have occurred. There may be a delay of
several days before these symptoms appear.
If you forget to take Levothyroxine Tablets
If you forget to take a dose, take another as soon as you remember. If
it is almost time for your next dose, then do not take the missed dose
at all. Do not take a double dose to make up for a forgotten tablet.
If you stop taking Levothyroxine Tablets
You should continue to take Levothyroxine Tablets for as long as your
doctor tells you to. Do not stop taking the medicine without talking to
your doctor first.
If you have any further questions on the use of this medicine, ask your
doctor or pharmacist.

4. Possible side effects
Like many medicines, this medicine can cause side effects, although
not everybody gets them. Most side effects occur if too many
Levothyroxine Tablets are taken.
Rarely, patients have had allergic reactions to levothyroxine.
Tell your doctor immediately if you get any of the following:
• rash or itching (you may have high levels of certain cells in your
blood, indicative of an allergy)
• swelling of tongue or lips or face
• fever
• liver problems (detected by a blood test)
• difficulty breathing
• joint pain
Side effects include:
Heart problems – existing problems may be made worse by
• fast or irregular heartbeats
• palpitations (awareness of beating of the heart)
• angina (chest pain)
Problems with your nervous system:
• headache
• nervousness
• excitability
• restlessness
• difficulty sleeping
• tremor
• mania (highly elevated mood, over talkative, over excited, over active)
Problems with your muscles:
• muscular weakness
• cramps
Problems with your digestive system:
• diarrhoea
• vomiting
Other side effects:
• flushing
• sweating

dislike of the heat
weight loss
irregular periods.

Older patients
Undetected overtreatment in older
patients could possibly increase the risk
of fractures and disturbed heart rhythm.
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
By reporting side effects you can help provide more information on the
safety of this medicine.

5. How to store Levothyroxine Tablets
Keep this medicine out of the sight and reach of children.
Do not use this medicine after the expiry date which is stated on the
label. The expiry date refers to the last day of that month.
Do not use this medicine if you notice signs of deterioration such as
Do not store above 25°C.
Store in the original container or package in order to protect from light
and moisture. Do not transfer the tablets to another container.
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
What Levothyroxine Tablets contain
The active ingredient in Levothyroxine Tablets is levothyroxine sodium.
Each tablet contains 27.8 micrograms of levothyroxine sodium
equivalent to 25 micrograms of anhydrous levothyroxine sodium.
Other ingredients are lactose, sucrose (fine powder), maize starch,
magnesium stearate.
What Levothyroxine Tablets look like and contents of the pack
Levothyroxine 25 micrograms Tablets are white, circular, curved
tablets marked TX25 on one face and CP on the reverse.
Levothyroxine 25 micrograms Tablets are available in polypropylene or
polyethylene (plastic) containers or blister strip packs of 28 tablets.
Marketing Authorisation Holder: Wockhardt UK Ltd, Ash Road North,
Wrexham, LL13 9UF, UK.
Manufacturer: CP Pharmaceuticals Ltd, Ash Road North, Wrexham,
LL13 9UF, UK.
Other formats:
To listen to or request a copy of this leaflet in Braille, large print or
audio please call, free of charge: 0800 198 5000 (UK Only)
Please be ready to give the following information:
Product name

Reference number

Levothyroxine 25 Micrograms Tablets


This is a service provided by the Royal National Institute of Blind People.
This leaflet was last revised 07/2016

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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.