Levirox

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

Levirox should not be taken with antithyroid drugs if the patient is pregnant (see "Pregnancy and breastfeeding" below).

Warnings and precautions

Before starting Levirox, tell your doctor or pharmacist if you have any of the following heart conditions:

• insufficient blood flow in the coronary arteries (angina pectoris),
• heart failure,
• rapid and irregular heart rhythm,
• high blood pressure,
• fatty deposits in the arteries (arteriosclerosis).

It is necessary to treat these conditions before starting Levirox or before performing a thyroid suppression test. During Levirox treatment, it is necessary to frequently monitor thyroid hormone levels. Tell your doctor if you are not sure if any of the above conditions apply to you or if you have not yet started treatment for them.
Your doctor will perform tests to check if you have adrenal or pituitary gland disorders or thyroid function disorders with uncontrolled excessive thyroid hormone production (autonomous thyroid function), as in such cases, appropriate treatment may be necessary before starting Levirox or before performing a thyroid suppression test.
When starting levothyroxine treatment in premature infants with very low birth weight, it is necessary to regularly monitor blood pressure, as a sudden decrease in blood pressure (so-called circulatory collapse) may occur.
Talk to your doctor:

Levirox with other medicines

Tell your doctor or pharmacist about all medicines you are taking, have recently taken, or plan to take, as Levirox may affect the way they work:

• antidiabetic medicines (medicines that lower blood sugar levels):Levirox may decrease the effect of antidiabetic medicines, so additional blood sugar level monitoring may be necessary, especially when starting Levirox treatment. During Levirox treatment, it may be necessary to adjust the dose of antidiabetic medicine.
• coumarin derivatives (medicines that prevent blood clot formation, such as warfarin):Levirox may enhance the effect of these medicines, which may increase the risk of bleeding, especially in the elderly. Therefore, regular monitoring of blood coagulation parameters may be necessary at the start and during Levirox treatment. During Levirox treatment, it may be necessary to adjust the dose of anticoagulant medicine.

If you are taking any of the following medicines with Levirox, you must follow the recommended time intervals between taking the medicines:

• bile acid sequestrants and cholesterol-lowering medicines (such as cholestyramine or colestipol):Take Levirox 4 to 5 hours before taking these medicines, as they may inhibit the absorption of Levirox from the gut.
• antacids (used to relieve heartburn caused by stomach acid), sucralfate (used to treat stomach and intestinal ulcers), other medicines containing aluminum, iron-containing medicines, or calcium-containing medicines:Take Levirox at least 2 hours before taking these medicines, as they may reduce the effect of Levirox.

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

• propylthiouracil (an antithyroid medicine),
• corticosteroids (anti-allergic and anti-inflammatory medicines),
• beta-adrenergic blockers (medicines that lower blood pressure, also used to treat heart conditions),
• sertraline (an antidepressant),
• chloroquine or proguanil (medicines used to treat or prevent malaria),
• medicines that stimulate certain liver enzymes, such as barbiturates (sedatives or sleeping pills) or carbamazepine (an antiepileptic medicine, also used to modify a certain type of pain or treat mood disorders),
• medicines containing estrogens, used in hormone replacement therapy during menopause and postmenopause or to prevent pregnancy,
• sevelamer (a phosphate binder used in patients with chronic kidney failure),
• tyrosine kinase inhibitors (medicines used to treat cancer and anti-inflammatory medicines),
• orlistat (a medicine used to treat obesity).

Tell your doctor or pharmacist if you are 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),
• dicumarol (a medicine that prevents blood clot formation),
• high-dose furosemide (above 250 mg; a diuretic),
• clofibrate (a medicine that lowers blood lipid levels).

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

• ritonavir, indinavir, lopinavir (protease inhibitors, medicines used to treat HIV infection),
• phenytoin (an antiepileptic medicine). Regular thyroid hormone level monitoring may be necessary, and the Levirox dose may need to be adjusted.

Tell your doctor if you are taking amiodarone (a medicine used to treat heart rhythm disorders), as it may affect thyroid function.
Tell your doctor about taking Levirox if a diagnostic or imaging test with a contrast agent containing iodine is necessary, as the test may affect thyroid function.
Tell your doctor or pharmacist about all medicines you are taking, have recently taken, or plan to take, including those available without a prescription.
Thyroid hormones should not be used to lose weight. Taking them will not cause weight loss if thyroid hormone levels are normal.
Increasing the dose without consulting a doctor may lead to severe and life-threatening side effects, especially if you are taking other weight loss medicines.

Levirox with food and drink

Tell your doctor if you consume soy products, especially if you change the amount of these products you eat. Soy products may reduce the absorption of Levirox from the gut, and therefore, it may be necessary to adjust the Levirox dose.

Pregnancy and breastfeeding

Continue taking Levirox during pregnancy. Talk to your doctor, as a dose adjustment may be necessary.
If Levirox was taken with an antithyroid medicine to treat excessive thyroid hormone production, your doctor will recommend stopping Levirox after becoming pregnant.
During breastfeeding, continue taking Levirox as recommended by your doctor. The amount of levothyroxine that passes into breast milk is too small to affect the baby.

Driving and using machines

No studies have been conducted on the effect of Levirox on the ability to drive or operate machines. It is not expected that Levirox will have any effect on the ability to drive or operate machines, as levothyroxine is identical to the hormone that occurs naturally.

Levirox contains sodium

This medicine contains less than 1 mmol (23 mg) of sodium per dose, which means it is essentially "sodium-free".

3. How to take Levirox

Always take this medicine exactly as your doctor or pharmacist has told you. If you are not sure, ask your doctor or pharmacist.
Your doctor will determine the appropriate dose for each patient individually, based on clinical evaluation and laboratory tests. Treatment usually starts with a small dose, which is increased every 2 to 4 weeks until the full dose, tailored to each patient, is reached.
In the first few weeks of treatment, laboratory tests will be necessary to allow your doctor to adjust the dose.
If a child is born with a thyroid disorder characterized by insufficient hormone production, it is essential to supplement them quickly. Therefore, your doctor may recommend a higher initial dose of 10 micrograms to 15 micrograms per kilogram of body weight per day for the first 3 months. Then, your doctor will adjust the dose individually.
Typical dose ranges are presented in the table below. Smaller, individually adjusted doses may be sufficient for:

• the elderly,
• patients with heart conditions,
• patients with severe or prolonged hypothyroidism,
• patients with low body weight or giant goiter.

Method of administration
Levirox is intended for oral use.
Take the single daily dose in the morning, on an empty stomach (at least 30 minutes before breakfast), with a small amount of liquid, e.g., half a glass of water.

Use in children

Infants should be given the entire daily dose of Levirox once a day, at least 30 minutes before the first meal of the day. Immediately before administration, crush the tablet and mix it with a small amount of water. Give the prepared suspension with a small additional amount of liquid. Prepare a fresh suspension of the medicine each time before administration.
Duration of treatment
The duration of treatment may vary depending on the reason for taking Levirox. Your doctor will discuss with you individually how long you need to take the medicine.
Most patients need to take Levirox for the rest of their lives.
The tablet can be divided into equal doses.

Overdose of Levirox

If you take more than the recommended dose, you may experience symptoms such as rapid heartbeat, restlessness, excitement, or involuntary movements. 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 conditions, cardiac symptoms can be life-threatening. In such cases, seek medical attention immediately.

Missed dose of Levirox

Do not take a double dose to make up for a missed dose. The next day, take the usual dose of the medicine.
If you have any further questions about taking Levirox, ask your doctor or pharmacist.

4. Possible side effects

Like all medicines, Levirox can cause side effects, although not everybody gets them.
If you take more than the recommended dose of Levirox or if you have poor tolerance to the prescribed dose (e.g., if the dose is increased too quickly), you may experience some of the following side effects:
Irregular or rapid heart rhythm, chest pain, headache, weakness or muscle cramps, hot flashes (feeling of heat and facial redness), fever, vomiting, menstrual disorders, pseudo-tumor cerebri (increased intracranial pressure), tremors, restlessness, sleep disturbances, sweating, weight loss.
If you experience any of these side effects, contact your doctor. Your doctor may decide to stop treatment for a few days or reduce the daily dose until the symptoms disappear.
It is possible to have an allergic reaction to the ingredients of Levirox (see section 6). Allergic reactions may include facial or throat swelling (angioedema), rash, or hives (frequency not known, cannot be estimated from available data). If you experience an allergic reaction, seek medical attention immediately.

Reporting side effects

If you experience any side effects, including those not listed in this leaflet, tell your doctor or pharmacist. You can also report side effects directly to the national reporting system:
Department of Pharmacovigilance, Office for Registration of Medicinal Products, Medical Devices, and Biocidal Products:
Jerozolimskie Avenue 181C, 02-222 Warsaw
phone: +48 22 49 21 301
fax: +48 22 49 21 309
Website: https://smz.ezdrowie.gov.pl
You can also report side effects to the marketing authorization holder.
By reporting side effects, you can help provide more information on the safety of this medicine.

5. How to store Levirox

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

6. Contents of the pack 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 silicon dioxide, 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, with "25" embossed on one side and a break line on the other side.
Levirox 50 micrograms, tablets are white or almost white, round tablets with a diameter of 7.5 mm, with "50" embossed on one side and a break line on the other side.
Levirox 75 micrograms, tablets are white or almost white, round tablets with a diameter of 7.5 mm, with "75" embossed on one side and a break line on the other side.
Levirox 100 micrograms, tablets are white or almost white, round tablets with a diameter of 7.5 mm, with "100" embossed on one side and a break line on the other side.
Levirox 125 micrograms, tablets are white or almost white, round tablets with a diameter of 7.5 mm, with "125" embossed on one side and a break line on the other side.
Levirox 150 micrograms, tablets are white or almost white, round tablets with a diameter of 7.5 mm, with "150" embossed on one side and a break line on the other side.
Levirox is available in cartons containing blisters.
Pack sizes:
100 tablets

Marketing authorization 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
To obtain more detailed information about this medicine, contact the local representative of the marketing authorization holder:
Orion Pharma Poland Sp. z o. o.
kontakt@orionpharma.info.pl

Date of last revision of the leaflet: