Eferox

Patient Information Leaflet: Eferox

Eferox,100 micrograms, tablets
Levothyroxine sodium

Important Information for Patients

• Please read this leaflet carefully before taking Eferox. It contains important information for patients.
• Keep this leaflet. You may need to read it again.
• If you have any questions or concerns, consult your doctor or pharmacist.
• This medicine has been prescribed specifically for you. Do not give it to others. It may harm them, even if their symptoms are the same as yours.
• If you experience any side effects, including those not listed in this leaflet, inform your doctor or pharmacist. See section 4.

Table of Contents

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

1. What is Eferox and what is it used for

Thyroxine is a hormone produced naturally in the body by the thyroid gland. Levothyroxine sodium is a synthetic form of this hormone.
Eferox is used to treat thyroid hormone deficiency and (or) to alleviate thyroid diseases and disorders.
Eferox is used:

• to supplement thyroid hormone deficiency in all forms of hypothyroidism (underactive thyroid) or after thyroid removal,
• to prevent goiter recurrence after goiter removal in patients with normal thyroid function,
• to treat goiter in patients with normal thyroid function,
• as combination therapy with antithyroid drugs in hyperthyroidism, after achieving a normal metabolic state of the thyroid,
• in cases of malignant thyroid cancer, especially after surgical procedures to inhibit tumor growth and as a supplement to replace missing thyroid hormone,
• in thyroid function suppression tests.

2. Important information before taking Eferox

When not to take Eferox

• if you are allergic to levothyroxine or any of the other ingredients of this medicine (listed in section 6);
• if you have untreated hyperthyroidism (thyrotoxicosis);
• if you have untreated adrenal insufficiency (adrenal gland disorder) and you are not receiving appropriate replacement therapy;
• if you have untreated hypopituitarism;
• if you have the following diseases or conditions:
• acute myocardial infarction
• acute myocarditis
• acute pancarditis
• in pregnancy, do not take Eferox with other antithyroid drugs.

Before starting treatment with Eferox, the following diseases or conditions must be excluded or treated:

• coronary artery disease;
• angina pectoris;
• atherosclerosis;
• hypertension;
• conditions in which the pituitary gland and (or) adrenal glands do not produce enough hormones (hypopituitarism and (or) adrenal insufficiency);
• autonomous thyroid function in patients, where areas of the thyroid gland produce uncontrolled amounts of thyroid hormone.

Warnings and precautions

Thyroid hormones are not suitable for weight loss. Taking thyroid hormones will not lead to weight loss in patients with normal thyroid hormone levels. Taking extra thyroid hormones without a doctor's prescription can cause serious, life-threatening side effects, especially when combined with other weight-loss medications (see section 2: "Eferox and other medicines").
If it is necessary to switch to another levothyroxine-containing medicine, thyroid function imbalance may occur. If you have any questions about switching medicines, discuss them with your doctor. Patients should be closely monitored (clinically and biologically) during the transition period. Inform your doctor if you experience any side effects, as this may indicate the need to adjust the dose (increase or decrease the dose).
Before starting Eferox, discuss the following with your doctor or pharmacist:

• if you have been suffering from hypothyroidism for a long time, for example, since birth or the disease was diagnosed in childhood;
• if you have heart disease, including angina pectoris, coronary artery disease, heart failure, arrhythmias, or hypertension;
• if you have recently had a heart attack;
• if you are taking anticoagulant medications (e.g., phenprocoumon). The dose of this medicine may need to be adjusted (see section 2: "Eferox and other medicines");
• if you are being treated for diabetes. The dose of your antidiabetic medication may need to be adjusted, as levothyroxine may increase blood sugar levels (see section 2: "Eferox and other medicines");
• if you are in menopause. Thyroid function should be monitored more frequently to avoid increased levothyroxine levels in the blood, which can cause osteoporosis (bone fragility);
• if you have epilepsy (seizures). When starting levothyroxine treatment or rapidly increasing the dose, seizures have been reported rarely;
• if you have myxedema (swelling of the skin and subcutaneous tissue), as the Eferox dose may need to be reduced;
• if you have small intestine disease, as it may cause absorption disorders (malabsorption syndrome, e.g., celiac disease, lactose intolerance) and may require treatment to ensure Eferox works properly;
• if you have adrenal insufficiency (adrenal gland disorder), pituitary dysfunction, or certain thyroid function disorders with uncontrolled excessive thyroid hormone production, as in such cases, appropriate treatment is necessary before starting Eferox;

Before starting Eferox, if you are going to have laboratory tests to check your thyroid hormone levels, inform your doctor or laboratory staff if you are currently taking or have recently taken biotin (also known as vitamin H, vitamin B7, or vitamin B8). Biotin may affect laboratory test results. Depending on the type of test, the results may be falsely elevated or decreased due to biotin intake. Your doctor may advise you to stop taking biotin before laboratory tests. Also, remember that other products you are taking, such as multivitamins or supplements for hair, skin, and nails, may also contain biotin, which can affect laboratory test results. If you are taking such products, inform your doctor or laboratory staff (see "Warnings and precautions").

• if you experience symptoms of psychotic disorders, consult your doctor.

When starting levothyroxine treatment in premature infants with very low birth weight, regularly monitor blood pressure, as a sudden drop in blood pressure (so-called circulatory collapse) may occur.
In elderly patients, especially those with heart disease, the dose should be adjusted carefully and individually. The doctor should monitor these patients.

Blood tests

Before starting levothyroxine treatment, your doctor will perform a blood test to check how much thyroxine your thyroid gland produces and what dose of the medicine you will need. After starting treatment, your doctor will recommend regular blood tests to check if the medicine is working properly.

Eferox and other medicines

Tell your doctor or pharmacist about all medicines you are taking or have recently taken, as well as any medicines you plan to take or use. This includes over-the-counter medicines, herbal medicines, and vitamin preparations. Many other medicines may affect the action of Eferox. Levothyroxine may also affect the action of other medicines.
Before undergoing a test using iodine-based contrast agents, inform your doctor that you are taking Eferox.
If you are currently taking or have recently taken biotin, you must inform your doctor and (or) laboratory staff if you are going to have laboratory tests for thyroid hormones. Biotin may affect laboratory test results (see "Warnings and precautions").
The following medicines may affect the action of levothyroxine:

• medicines used in epilepsy, such as carbamazepine, phenytoin, primidone, and barbiturates
• medicines containing St. John's Wort (some herbal medicines)
• sertraline, lithium - medicines used in depression, mood disorders, and anxiety
• statins, such as simvastatin and lovastatin (medicines used to treat high cholesterol)
• rifampicin - a medicine used to treat infections
• imatinib, sunitinib, 5-fluorouracil - medicines used to treat certain types of cancer
• beta-adrenergic blockers, such as propranolol, atenolol, and sotalol - medicines used to treat high blood pressure and heart disease
• hormonal medicines containing estrogen, used in hormone replacement therapy and hormonal contraception ("the pill")
• hormonal medicines containing androgens, used in hormone replacement therapy in men
• glucocorticoids, such as cortisol, hydrocortisone, prednisolone, and dexamethasone - medicines used to treat inflammatory conditions

Eferox should be taken at least 4 to 5 hours before taking the following medicines:

• calcium, magnesium, aluminum, or iron supplements, lanthanum
• cholestyramine, colestipol, or clofibrate - medicines used to lower high cholesterol levels
• sodium polystyrene sulfonate - used to treat kidney disease
• orlistat - used for weight loss
• cimetidine - used to reduce stomach acid production
• proton pump inhibitors, such as omeprazole, esomeprazole - medicines used to reduce stomach acid production
• sucralfate, antacids - used to treat stomach ulcers

Eferox may affect the action of the following medicines:

• anticoagulant medicines that prevent blood clots, such as warfarin, dicumarol, and phenprocoumon
• medicines used to treat diabetes, such as insulin and metformin
• tricyclic antidepressants, such as amitriptyline, imipramine, and doxepin
• 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 medicines)
• digoxin - a medicine used to treat heart disease
• phenytoin - a medicine used to treat epilepsy

Eferox with food and drink

Products and foods containing soy, high in fiber, may affect levothyroxine absorption. Therefore, the levothyroxine dose may need to be adjusted by your doctor.

Pregnancy and breastfeeding

If you are pregnant or breastfeeding, think you may be pregnant, or plan to have a baby, consult your doctor or pharmacist before taking this medicine.
Uninterrupted thyroid hormone treatment is particularly important during pregnancy and breastfeeding and must be continued under medical supervision.
During pregnancy, the need for levothyroxine may increase due to increased estrogen levels in the blood. Therefore, thyroid function should be monitored during and after pregnancy, and the levothyroxine dose should be adjusted accordingly.
Even when taking high doses of levothyroxine, the amount of thyroid hormone that passes into breast milk during breastfeeding is very small and harmless.
During pregnancy and breastfeeding, suppression tests should not be performed.

Driving and using machines

Eferox is not expected to affect your ability to drive or use machines, as the levothyroxine in this medicine is identical to the thyroid hormone that occurs naturally in the body.

Eferox contains sodium

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

3. How to take Eferox

Always take this medicine exactly as your doctor or pharmacist has told you. If you are not sure, consult your doctor or pharmacist.
In elderly patients, patients with coronary artery disease, and patients with severe or chronic hypothyroidism, thyroid hormone treatment should be started with caution. In these patients, treatment should be started with a small initial dose, which should then be slowly increased at longer intervals, with frequent monitoring of thyroid hormone levels. Experience has shown that smaller doses are also sufficient for people with low body weight and patients with large goiters.
Dosage

For individual treatment, Eferox tablets are available in strengths from 25 to 200 micrograms, which means that in most cases, only one tablet needs to be taken per day.
Your doctor will determine the individual dose for you based on the results of your tests and laboratory results. Treatment usually starts with a small dose, which is increased every 2 to 4 weeks until the full dose, adjusted individually for you, is reached. In the first few weeks of treatment, you will be prescribed laboratory tests to allow your doctor to adjust the appropriate dose.

Method of administration
The entire daily dose should be taken in the morning, on an empty stomach, at least half an hour before breakfast, as the active substance is better absorbed on an empty stomach than before or after a meal. The tablets should be swallowed whole, without chewing, with a glass of water.
Infants should receive the entire daily dose at least half an hour before the first meal, preferably with a small amount of water to facilitate swallowing. If necessary, the tablet can be divided.
It is not recommended to crush the tablet or prepare a suspension in water or other liquids, as this may lead to incorrect dosing.
Eferox tablets can be divided into equal doses.

Tablet division

Place the tablet on a hard, flat surface with the dividing line facing up. To divide the tablet, press your thumb directly on the center of the tablet.

Duration of treatment
The medicine should be taken for as long as your doctor recommends.
If you have hypothyroidism or have had your thyroid gland removed due to malignant thyroid cancer, you will usually take Eferox for the rest of your life.
In the case of goiter and to prevent goiter recurrence, Eferox should be taken for several months or years, or even for the rest of your life.
In combination therapy for hyperthyroidism, Eferox should be taken for as long as you are taking antithyroid medication (thyreostatic drugs).
In the treatment of goiter with normal thyroid function, the medicine should be taken for 6 months to 2 years. If Eferox does not produce the desired results within this period, other treatment options should be considered.
To perform thyroid function suppression tests, take 150 or 200 micrograms of Eferox per day for 14 days.

Overdose of Eferox

If you (or someone else) have taken more tablets than you should, or if you suspect that a child has taken some, contact your doctor, the emergency department of the nearest hospital, or the poison control center immediately.
Overdose symptoms may include: excitement, confusion, irritability, fever, chest pain (angina pectoris), rapid or irregular heartbeat, heart failure, myocardial infarction, rapid breathing, muscle cramps, headache, anxiety, overstimulation, flushing, sweating, diarrhea, tremors, difficulty sleeping, anxiety or nervousness, feeling of physical or emotional exhaustion, seizures.
These symptoms may last up to 6 days. Bring any remaining tablets and this leaflet with you so that medical personnel can determine exactly which medicine you have taken.

Missing a dose of Eferox

If you miss a dose, take your usual dose at the next scheduled time. Do not take a double dose to make up for the missed dose. If you are unsure, consult your doctor or pharmacist.

Stopping Eferox treatment

To ensure effective treatment, regularly take Eferox in the prescribed doses. Do not change, stop, or discontinue prescribed treatment without consulting your doctor, as symptoms may recur.
If you have any further questions about using this medicine, consult your doctor or pharmacist.

4. Possible side effects

Like all medicines, Eferox can cause side effects, although not everybody gets them.

Stop taking the tablets and go to the hospital immediately if you experience:

• an allergic reaction, such as: facial swelling, tongue, lips, and (or) throat swelling and (or) difficulty swallowing or hives that can cause breathing difficulties (angioedema), severe skin itching with raised bumps, joint pain, increased sensitivity to sunlight, general malaise (frequency not known). You may need urgent medical attention.

In some patients, a severe reaction to high thyroid hormone levels may occur, known as a "thyroid crisis". Stop taking the tablets and go to the hospital immediately if you experience any of the following symptoms (frequency not known):

• very high fever, rapid heartbeat, irregular heartbeat, low blood pressure, heart failure, jaundice, confusion, seizures, and coma.

Inform your doctor or pharmacist if you experience any of the following side effects or if they worsen or if you notice any other side effects not listed in this leaflet.

Most side effects are similar to symptoms of hyperthyroidism (when the thyroid gland produces too much thyroxine) and are caused by taking too high a dose of the medicine. Symptoms usually disappear after reducing the dose or stopping the tablets. Inform your doctor if you experience any side effects. Your doctor will decide whether to reduce the daily dose or stop the medicine for a few days. However, do not change the dose or stop taking the tablets without consulting your doctor first.
Frequency not known:frequency cannot be estimated from the available data

• increased appetite
• anxiety, overstimulation, difficulty sleeping (insomnia)
• tremors, headache, seizures
• chest pain (angina pectoris), palpitations, irregular or rapid heartbeat, heart failure, myocardial infarction
• high blood pressure (hypertension), sudden flushing
• shortness of breath (dyspnea)
• diarrhea, nausea (nausea), vomiting, abdominal pain
• increased sweating, itching, skin rash, hives
• muscle cramps, muscle weakness, joint pain
• decreased bone density (osteoporosis), especially in postmenopausal women taking high doses of the medicine for a long time
• in women: irregular menstrual periods
• fever (high temperature), swelling, general malaise
• weight loss
• hyperthyroidism

Additional side effects in children
Rare:may affect up to 1 in 1,000 people

• increased intracranial pressure in children, which is not caused by a tumor or other diseases (benign intracranial hypertension).

Frequency not known:frequency cannot be estimated from the available data

• slowed or stopped growth in children, caused by changes in bone development
• temporary hair loss in children
• skull deformity in infants, caused by premature closure of bone growth plates in children (craniosynostosis)
• heat intolerance

In case of hypersensitivity to levothyroxine or any of the other ingredients of Eferox, allergic reactions affecting the skin and respiratory tract may occur.

Reporting side effects

If you experience any side effects, including those not listed in this leaflet, inform your doctor or pharmacist, or nurse. Side effects can be reported directly to the Department of Drug Safety Monitoring of the Office for Registration of Medicinal Products, Medical Devices, and Biocidal Products:
Aleje Jerozolimskie 181C, 02-222 Warsaw, tel.: 22 49-21-301, fax: 22 49-21-309,
website: https://smz.ezdrowie.gov.pl
Side effects can also be reported 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 Eferox

Keep the medicine out of the sight and reach of children.
Do not use this medicine after the expiry date stated on the blister pack and carton after EXP. The expiry date refers to the last day of the month.
Do not store above 30°C.
Medicines should not be disposed of via wastewater or household waste. Ask your pharmacist how to dispose of medicines that are no longer needed. This will help protect the environment.

6. Contents of the pack and other information

What Eferox contains

• The active substance is levothyroxine sodium anhydrous.

Eferox, 100 micrograms, tablets
Each tablet contains 100 micrograms of levothyroxine sodium.

• The other ingredients are: microcrystalline cellulose, maize starch, magnesium oxide, heavy; sodium carboxymethylcellulose (type A) and magnesium stearate.

What Eferox looks like and contents of the pack

Eferox: tablets are white, round, uncoated, divisible by pressure, with a dividing line on one side and a numerical marking corresponding to the strength (i.e., 100) embossed on the other side. The tablets are approximately 7 mm in diameter and 3 mm in height.
Eferox 100 micrograms is available in blisters containing 15, 20, 25, 30, 50, 60, 84, 90, and 100 tablets in a carton.
Not all pack sizes may be marketed.

Marketing authorization holder

Aristo Pharma Sp. z o.o.
ul. Baletowa 30
02-867 Warsaw
tel: +48 22 855 40 93

Manufacturer

Aristo Pharma GmbH
Wallenroder Straße 8–10
13435 Berlin
Germany
Lindopharm GmbH
Neustraße 82
40721 Hilden
Germany

This medicine is authorized in the Member States of the European Economic Area and in the United Kingdom (Northern Ireland) under the following names:

Austria
Levothyroxin Aristo 100 Mikrogramm Tabletten
Germany
L-Thyroxin Aristo 100 Mikrogramm Tabletten
Czech Republic
Levothyroxine Aristo 100 mikrogramů tablety
Finland
Levothyroxine Aristo 100 mikrog tablettia
Spain
Levotiroxina Aristo 100 microgramos comprimidos EFG
Netherlands
Levothyroxinenatrium Aristo 100 microgram tabletten
Ireland
Levothyroxine sodium Aristo 100 microgram tablets
Poland
Eferox 100 mikrogramów tabletki
Portugal
Eferox 100 microgramas comprimidos
Sweden
Levothyroxine Aristo 100 mikrogram tabletter
Italy
Levotiroxina DOC 100 mikrogrammi compresse
Date of last revision of the leaflet: