Levirox

Patient Information Leaflet

Levirox, 25 micrograms, tablets
Levirox, 50 micrograms, tablets
Levirox, 75 micrograms, tablets
Levirox, 100 micrograms, tablets
Levirox, 125 micrograms, tablets
Levirox, 150 micrograms, tablets
Levothyroxinum natricum
Please read all of this leaflet carefully before 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, please ask your doctor or pharmacist.
• This medicine has been prescribed for a specific individual. Do not pass it on to others. It may harm someone else, even if their symptoms are the same.
• If you experience any adverse effects, including any not listed in this leaflet, tell your doctor or pharmacist. See section 4.

Leaflet Contents:

1. What Levirox is and what it is used for
2. What you need to know before taking Levirox
3. How to take Levirox
4. Possible side effects
5. How to store Levirox
6. Contents of the pack and other information

1. What Levirox is and what it is used for

Levothyroxine, the active substance in Levirox, is a synthetic thyroid hormone used for the treatment of thyroid disorders and diseases. It has the same action as the thyroid hormones naturally produced in the body.
Levirox is used:

• for the treatment of mild goitre in patients with normal thyroid function;
• to prevent recurrence of goitre in patients after surgery;
• to replace deficient natural thyroid hormones when the thyroid gland does not produce sufficient amounts;
• to suppress tumour growth in patients with thyroid cancer.

Levirox 25 micrograms, 50 micrograms, 75 micrograms, and 100 micrograms are also used to normalize thyroid hormone levels in patients who are being treated with antithyroid drugs due to excessive production of thyroid hormones.
Levirox 100 micrograms and 150 micrograms may also be used in tests evaluating thyroid function.

2. Important information before using Levirox

When not to use Levirox
Do not use Levirox if the patient has any of the following conditions:

• hypersensitivity to sodium levothyroxine or any of the other ingredients of this medicine (listed in section 6),
• adrenal insufficiency (adrenal failure) and the patient is not receiving appropriate replacement therapy,
• untreated pituitary insufficiency or if thyroid hormones are being produced in excessive amounts (hyperthyroidism),
• acute heart disease (myocardial infarction or myocarditis).

Levirox must not be used concomitantly with antithyroid drugs if the patient is pregnant (see section "Pregnancy and breastfeeding" below).

Warnings and precautions
Before starting treatment with Levirox, inform your doctor or pharmacist if you have any of the following heart conditions:

• inadequate blood flow in the blood vessels of the heart (angina pectoris),
• heart failure,
• rapid or irregular heartbeat,
• arterial hypertension,
• fatty deposits in the arteries (atherosclerosis).

These disorders must be treated before starting therapy with Levirox or before performing a thyroid suppression test. During treatment with Levirox, thyroid hormone levels should be monitored regularly. Inform your doctor if you are unsure whether any of the above conditions apply to you or if treatment has not yet been initiated.

Your doctor will perform tests to check whether you have adrenal or pituitary dysfunction or a thyroid disorder with uncontrolled overproduction of thyroid hormones (autonomous thyroid function), as appropriate treatment may be required before starting Levirox or performing a thyroid suppression test.

When initiating levothyroxine treatment in preterm infants with very low birth weight, blood pressure should be monitored regularly, as a sudden drop in blood pressure (so-called circulatory collapse) may occur.

Talk to your doctor:

• if you are in menopause or postmenopausal; your doctor may recommend regular monitoring of thyroid function due to the risk of osteoporosis;
• when switching from one levothyroxine-containing medicine to another. The effects of these medicines may differ slightly, and therefore close monitoring of clinical and biochemical parameters may be necessary during the transition period. Inform your doctor if you experience any adverse effects, as dose adjustment may be required;
• when starting, stopping, or changing treatment with orlistat (a medicine used in the treatment of obesity; more frequent monitoring and dose adjustment may be necessary);
• if you have symptoms of psychotic disorders (your doctor may recommend more frequent monitoring and dose adjustment);
• if you have coeliac disease, inflammatory bowel disease, Helicobacter pylori infection, lactose intolerance, or gastric mucosal inflammation.

Levirox and other medicines
Tell your doctor or pharmacist about all medicines you are currently taking, have recently taken, or plan to take, as Levirox may affect the action of these medicines:

• antidiabetic medicines (medicines that lower blood glucose levels): Levirox may reduce the effectiveness of antidiabetic medicines, so additional monitoring of blood glucose levels may be necessary, especially at the beginning of Levirox treatment. Dose adjustment of the antidiabetic medicine may be required during Levirox therapy.
• coumarin derivatives (medicines preventing blood clot formation, such as warfarin): Levirox may enhance the effect of these medicines, increasing the risk of bleeding, particularly in elderly patients. Therefore, regular monitoring of blood coagulation parameters may be necessary at the beginning and during Levirox treatment. Dose adjustment of the coumarin-derived anticoagulant may be required during Levirox therapy.

If taking any of the following medicines concomitantly with Levirox, it is essential to follow the recommended time intervals between administration of the respective medicines:

• bile acid sequestrants and medicines reducing high cholesterol levels (such as cholestyramine or colestipol): Levirox should be taken 4 to 5 hours before these medicines, as they may inhibit the intestinal absorption of Levirox.
• antacids (used to relieve acid-related indigestion), sucralfate (used in the treatment of gastric and intestinal ulcers), other medicines containing aluminium, iron-containing medicines, calcium-containing medicines: Levirox should be taken at least 2 hours before these medicines, as otherwise they may reduce the effectiveness of Levirox.

Tell your doctor or pharmacist if you are currently taking, have recently taken, or plan to take any of the following medicines, as they may reduce the effectiveness of Levirox:

• propylthiouracil (an antithyroid medicine),
• glucocorticoids (anti-allergic and anti-inflammatory medicines),
• beta-blockers (medicines reducing blood pressure, also used in the treatment of heart diseases),
• sertraline (an antidepressant),
• chloroquine or proguanil (medicines used in the treatment or prevention of malaria),
• medicines inducing certain liver enzymes, such as barbiturates (sedatives, hypnotics) or carbamazepine (an anticonvulsant, also used to modify certain types of pain or treat mood disorders),
• estrogen-containing medicines, used in hormone replacement therapy during and after menopause or for contraception,
• sevelamer (a phosphate binder used in patients with chronic kidney failure),
• tyrosine kinase inhibitors (medicines used in cancer treatment and anti-inflammatory therapy),
• orlistat (a medicine used in the treatment of obesity).

Tell your doctor or pharmacist if you are currently taking, have recently taken, or plan to take any of the following medicines, as they may enhance the effect of Levirox:

• salicylates (medicines used to relieve pain and reduce fever),
• dicoumarol (a medicine preventing blood clot formation),
• high-dose furosemide, above 250 mg (a diuretic),
• clofibrate (a medicine reducing blood lipid levels).

Tell your doctor or pharmacist if you are currently taking, have recently taken, or plan to take any of the following medicines, as they may affect the action of Levirox:

• ritonavir, indinavir, lopinavir (protease inhibitors, medicines used in the treatment of HIV infections),
• phenytoin (an anticonvulsant). Regular monitoring of thyroid hormone levels and dose adjustment of Levirox may be necessary.

Inform your doctor if you are taking amiodarone (a medicine used in the treatment of cardiac arrhythmias), as this medicine may affect thyroid function.

Inform your doctor that you are taking Levirox if a diagnostic or imaging procedure involving administration of an iodine-containing contrast agent is required, as such procedures involve an injection that may affect thyroid function.

Tell your doctor or pharmacist about all medicines you are currently taking or have recently taken, including those obtained without a prescription.

Thyroid hormones should not be used for weight reduction. Taking them will not lead to weight loss if thyroid hormone levels are adequately maintained. Increasing the dose without consulting your doctor may result in severe and potentially life-threatening adverse effects, especially if you are also taking other weight-loss medicines.

Levirox with food and drink
Inform your doctor if you consume soy-containing products, especially if the amount consumed changes. Soy-containing products may reduce the intestinal absorption of Levirox, and therefore dose adjustment of Levirox may be necessary.

Pregnancy and breastfeeding
Levirox should be continued during pregnancy. Talk to your doctor, as dose adjustment may be necessary.

If Levirox was used concomitantly with an antithyroid medicine for the treatment of excessive thyroid hormone production, your doctor will advise you to discontinue Levirox after becoming pregnant.

During breastfeeding, continue taking Levirox as directed by your doctor. The amount of levothyroxine that passes into breast milk is too low to affect the infant.

Driving and operating machinery
No studies have been conducted on the effect of Levirox on the ability to drive or operate machinery. Levirox is not expected to affect the ability to drive or operate machinery, as levothyroxine is identical to the naturally occurring hormone.

Levirox contains sodium
This medicine contains less than 1 mmol (23 mg) of sodium per dose, i.e. the medicine is considered "sodium-free".

3. How to take Levirox

This medicine should always be taken exactly as directed by your doctor or pharmacist.
If in doubt, consult your doctor or pharmacist.
Your doctor will determine the appropriate individual dose for each patient based on clinical evaluation
and laboratory tests. Treatment usually starts with a low dose, which is increased every 2 to
4 weeks until the full, individually adjusted dose is reached.
During the first weeks of treatment, laboratory tests will be necessary to allow your doctor
to adjust the appropriate dose.
If a child is born with a thyroid disease involving insufficient production of thyroid hormones,
it is important to replace them promptly. Therefore, your doctor may recommend a higher initial dose
of 10 to 15 micrograms per kg of body weight per day for the first 3 months. Afterwards,
your doctor will adjust the dose individually.
Typical dose ranges are shown in the table below. Lower, individually adjusted doses may be sufficient for:

• elderly patients,
• patients with heart disease,
• patients with severe or long-standing hypothyroidism,
• patients with low body weight or with giant goitre.

Method of administration
Levirox is intended for oral use.
The single daily dose should be taken in the morning on an empty stomach (at least half an hour before breakfast), preferably with a small amount of liquid, e.g. half a glass of water.
Use in children
For infants, the entire daily dose of Levirox should be administered once daily, at least half an hour before the first meal of the day. Immediately before administration, the tablet should be crushed and mixed with a small amount of water. The resulting suspension should be given with a small additional amount of liquid. A fresh suspension should be prepared each time before administration.
Duration of treatment
The duration of treatment may vary depending on the reason for which Levirox is used. The physician will discuss individually with each patient how long the medication should be taken. Most patients need to take Levirox for life.
The tablet may be divided into equal doses.
Administration of a higher than recommended dose of Levirox
If a higher than recommended dose is taken, symptoms such as rapid heartbeat, anxiety, agitation, or involuntary movements may occur. In patients with neurological disorders such as epilepsy, single seizures have been observed.
In patients at risk of psychotic disorders, symptoms of acute psychosis may occur.
In patients with heart diseases, cardiac symptoms may be life-threatening. In such cases, medical advice should be sought immediately.
Missed dose of Levirox
Do not take a double dose to make up for a missed dose. The next day, take the usual prescribed dose.
If there are any further doubts regarding the use of Levirox, consult a physician or pharmacist.

4. Possible adverse reactions

Like all medicines, this medicine can cause adverse reactions, although not everyone experiences them.
If a higher dose of Levirox than recommended is taken, or if the recommended dose is poorly tolerated
(e.g. when the dose is increased too quickly), some of the following adverse reactions may occur:
Irregular or rapid heartbeat, chest pain, headache, weakness or muscle cramps, hot flushes (feeling of warmth and facial flushing), fever, vomiting, menstrual disturbances, pseudotumor cerebri (increased intracranial pressure), tremor, motor restlessness, sleep disturbances, sweating, weight loss, diarrhoea.
If any of the above adverse reactions occur, contact your doctor. The doctor may decide to interrupt treatment for several days or reduce the daily dose until symptoms resolve.
Allergic reactions to the components of Levirox may occur (see section 6, "What Levirox contains").
Allergic reactions may include swelling of the face or throat (angioedema), rash or urticaria (frequency unknown, cannot be estimated from available data). If such an allergic reaction occurs, seek medical advice immediately.
Reporting of adverse reactions
If any adverse symptoms occur, including any adverse effects not listed in this leaflet, inform your doctor or pharmacist. Adverse reactions can be reported directly to the Department of Monitoring of Adverse Drug Reactions at the Office for Registration of Medicinal Products, Medical Devices and Biocidal Products:
Al. Jerozolimskie 181C, 02-222 Warsaw
Tel.: +48 22 49 21 301
Fax: +48 22 49 21 309
Website: https://smz.ezdrowie.gov.pl
Adverse reactions can also be reported to the marketing authorization holder.
Reporting adverse reactions helps to provide more information on the safety of this medicine.

5. How to store Levirox

Keep this medicine out of sight and reach of children.
Do not use this medicine after the expiry date stated on the blister pack or cardboard
container. The expiry date refers to the last day of the stated month.
Do not store above 25°C.
Medicines must not be disposed of via the sewage system or household waste. Ask your
pharmacist how to dispose of medicines no longer required. Such measures will help
protect the environment.

6. Contents of the package and other information

What Levirox contains

• The active substance is levothyroxine sodium. Each tablet contains 25 micrograms, 50 micrograms, 75 micrograms, 100 micrograms, 125 micrograms, or 150 micrograms of levothyroxine sodium.
• The other ingredients are: microcrystalline cellulose, colloidal anhydrous silica, sodium croscarmellose, and sodium stearyl fumarate.

What Levirox looks like and contents of the pack
Levirox 25 micrograms tablets are white to almost white, round tablets with a diameter of 7.5 mm,
imprinted with "25" on one side and a division line on the other side.
Levirox 50 micrograms tablets are white or almost white, round tablets with a diameter of 7.5 mm,
imprinted with "50" on one side and a division line on the other side.
Levirox 75 micrograms tablets are white or almost white, round tablets with a diameter of 7.5 mm,
imprinted with "75" on one side and a division line on the other side.
Levirox 100 micrograms tablets are white or almost white, round tablets with a diameter of 7.5 mm,
imprinted with "100" on one side and a division line on the other side.
Levirox 125 micrograms tablets are white or almost white, round tablets with a diameter of 7.5 mm,
imprinted with "125" on one side and a division line on the other side.
Levirox 150 micrograms tablets are white or almost white, round tablets with a diameter of 7.5 mm,
imprinted with "150" on one side and a division line on the other side.
Levirox is available in cardboard boxes containing blisters.
Pack sizes:
100 tablets

Marketing Authorisation Holder
Orion Corporation
Orionintie 1
02200 Espoo
Finland

Manufacturer/Importer
Orion Corporation Orion Pharma
Orionintie 1
02200 Espoo
Finland
Orion Corporation Orion Pharma
Joensuunkatu 7
24100 Salo
Finland

For further information on this medicinal product, please contact the local representative of the Marketing Authorisation Holder:
Orion Pharma Poland Sp. z o.o.
[email protected]