Althixin

Leaflet accompanying the packaging: patient information

Althyxin, 25 micrograms/5 mL, oral solution

Althyxin, 50 micrograms/5 mL, oral solution

Althyxin, 100 micrograms/5 mL, oral solution

Levothyroxine sodium

Read the leaflet carefully before taking the medicine, as it contains important information for the patient.

• Keep this leaflet, so you can read it again if you need to.
• If you have any doubts, consult your doctor or pharmacist.
• This medicine has been prescribed specifically for you. Do not pass it on to others. The medicine may harm another person, even if their symptoms are the same.
• If the patient experiences any side effects, including any not listed in this leaflet, they should tell their doctor or pharmacist. See section 4.

Table of contents of the leaflet

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

1. What is Althyxin and what is it used for

The active substance of Althyxin is levothyroxine sodium.
The medicine is used to treat hypothyroidism - a condition in which the thyroid gland does not produce enough thyroxine to meet the body's needs.
Althyxin is also used to treat thyroid cancer and non-toxic diffuse goiter or Hashimoto's thyroiditis, conditions in which the thyroid gland becomes enlarged, causing swelling in the front of the neck.

2. Important information before taking Althyxin

Do not take Althyxin if you have:

• an allergy (hypersensitivity) to levothyroxine sodium or any of the other ingredients of this medicine (listed in section 6),
• adrenal insufficiency and are not receiving appropriate replacement treatment with corticosteroids,
• untreated hypopituitarism or if thyroid hormones are being overproduced (hyperthyroidism),
• myocardial infarction (acute myocardial infarction), myocarditis (acute myocarditis) or pericarditis (acute pericarditis). Do not take this medicine at the same time as other medicines used to treat hyperthyroidism, if you are pregnant (see "Pregnancy and breastfeeding").

Warnings and precautions

Before starting to take Althyxin, discuss it with your doctor or pharmacist if:

• you have heart disease, circulatory disorders or high blood pressure.
• you have hyperthyroidism (thyrotoxicosis), adrenal insufficiency, diabetes or have had hypothyroidism for some time.
• you are going to have laboratory tests to check your thyroid hormone levels, you should inform your doctor or laboratory staff if you are taking or have recently taken biotin (also known as vitamin H, vitamin B7 or vitamin B8). Biotin may affect the results of laboratory tests. Depending on the type of test, the results may be falsely elevated or falsely decreased due to biotin intake. Your doctor may advise you to stop taking biotin before having laboratory tests. You should also remember that other products you are taking, such as multivitamins or supplements for hair, skin and nails, may also contain biotin. This may affect the results of laboratory tests. If you are taking such products, you should inform your doctor or laboratory staff (see "Althyxin and other medicines").

In the event of a change of medicine to another levothyroxine-containing medicine, thyroid hormone imbalance may occur. You should consult your doctor if you have any questions about changing medicines. During the transition period, close monitoring of clinical and biochemical parameters is necessary. You should inform your doctor if you experience any side effects, as it may be necessary to increase or decrease the dose.
Thyroid hormones are not suitable for weight loss. Taking them will not cause weight loss if thyroid hormone levels are within the normal range.
Increasing the dose of the medicine without a doctor's recommendation may lead to serious and life-threatening side effects, especially when the medicine is taken in combination with other weight loss medicines.

Children

During the first few months of treatment, partial hair loss may occur, but this effect is usually temporary and subsequent hair regrowth usually occurs.
When starting treatment with levothyroxine in premature infants with very low birth weight, special caution should be exercised. In these infants, blood pressure should be regularly monitored, as a sudden drop in blood pressure (so-called circulatory collapse) may occur (see section 4).

Althyxin and other medicines

Tell your doctor or pharmacist about all medicines you are taking now or have taken recently, as well as any medicines you plan to take.
Althyxin may affect the action of some medicines, and some medicines may affect the action of Althyxin. In particular, you should inform your doctor or pharmacist about taking the following medicines:

• blood thinning medicines (e.g. warfarin),
• antidepressants (e.g. sertraline, imipramine, amitriptyline),
• antiepileptic medicines (e.g. phenytoin, phenobarbital, carbamazepine),
• antidiabetic medicines,
• rifampicin (used to treat infections, especially tuberculosis),
• digoxin or amiodarone (used to treat heart conditions),
• propranolol (used to treat high blood pressure), lovastatin (used to treat high cholesterol) or phenylbutazone or acetylsalicylic acid (anti-inflammatory medicines),
• estrogens, estrogen-containing medicines and oral contraceptives, androgens or corticosteroids,
• other medicines, including those you have bought yourself without a prescription,
• sucralfate, cimetidine or aluminum hydroxide used to treat stomach ulcers,
• other aluminum-containing medicines,
• cholestyramine or colestyvelam used to lower cholesterol levels, sodium polystyrene sulfonate, calcium or iron supplements.

Althyxin can be taken with the following medicines, but not at the same time:

• chloroquine or proguanil used for malaria prophylaxis,
• protease inhibitors (e.g. ritonavir, indinavir and lopinavir) used to treat HIV infection,
• sevelamer (used to treat high phosphate levels in the blood in patients with kidney failure),
• tyrosine kinase inhibitors (e.g. imatinib and sunitinib) used to treat cancer,
• propylthiouracil (used to treat hyperthyroidism),
• β-adrenergic blockers (used to treat high blood pressure and heart conditions),
• sympathomimetics (medicines that act by stimulating the sympathetic nervous system),
• glucocorticoids (steroid hormones used to treat adrenal insufficiency and other conditions),
• iodine-containing contrast agents (used to increase the visibility of vascular structures and organs during radiographic procedures),
• orlistat (a medicine used to treat obesity).
• medicines containing St. John's wort (some herbal medicines).

In the event of planned hospitalization and surgery, you should inform the anesthesiologist or other medical staff that you are taking Althyxin. The medicine may interact with an anesthetic (ketamine) that may be administered to you before surgery.
If you are currently taking or have recently taken biotin, you must inform your doctor or laboratory staff if you are to have thyroid hormone laboratory tests. Biotin may affect the results of laboratory tests (see "Warnings and precautions").
Proton pump inhibitors (such as omeprazole, esomeprazole, pantoprazole, rabeprazole and lansoprazole) are used to reduce stomach acid production, which may weaken the absorption of levothyroxine from the intestine and make it less effective. If you are taking levothyroxine during treatment with proton pump inhibitors, your doctor should monitor your thyroid function and modify the dose of Althyxin if necessary.

Althyxin with food and drink

Soy products may interact with levothyroxine. You should consult your doctor or pharmacist.

Pregnancy and breastfeeding

Before taking any medicine, you should consult your doctor or pharmacist.
If you are pregnant or breastfeeding, think you may be pregnant or plan to have a child, you should consult your doctor or pharmacist before taking this medicine.

Driving and using machines

It is unlikely that the medicine will affect your ability to drive or use machines.

Althyxin contains methyl parahydroxybenzoate sodium, glycerol and sodium

Methyl parahydroxybenzoate sodium may cause allergic reactions (possible late reactions).
Glycerol may cause headache, stomach upset and diarrhea.
This medicine contains less than 1 mmol (23 mg) of sodium per 5 mL, i.e. the medicine is considered "sodium-free".

3. How to take Althyxin

This medicine should always be taken exactly as directed by your doctor or pharmacist. If you are unsure, consult your doctor or pharmacist.
Your doctor will determine your individual dose based on your condition. Your doctor will order blood tests at regular intervals to monitor your response to treatment.
In the event of a change from levothyroxine oral solution to tablets or from tablets to oral solution, your doctor will closely monitor your condition. The same applies to a change from one levothyroxine oral solution to another.

Usual daily doses are:

Adults and children over 12 years:

The initial dose is 50 to 100 micrograms per day, increased by 25 to 50 micrograms every 3 to 4 weeks, until the dose suitable for the patient's condition is reached. The usual maintenance dose is 100 to 200 micrograms per day.
In the case of non-toxic diffuse goiter or Hashimoto's thyroiditis, the recommended dose is 50 to 200 micrograms per day.
In the treatment of thyroid cancer, the recommended dose is 150 to 300 micrograms per day.

Elderly patients (over 50 years)

The initial dose is 12.5 micrograms per day, increased by 12.5 micrograms every 4 weeks until the correct dose is reached. The usual target dose is between 50 and 200 micrograms per day. This dose also applies to patients with severe hypothyroidism and patients with heart disease.

Children under 12 years:

The dose for children depends on their age, weight and the condition being treated. The child should be monitored to ensure they are receiving the correct dose. The medicine should be given to the child in the morning or evening, before or with food, but it should be given in the same way every day.
Congenital hypothyroidism in infants:
Initially 10 to 15 micrograms/kg body weight per day for the first 3 months. The dose will then be adjusted according to the response to treatment.
Acquired hypothyroidism in children:
Initially 12.5 to 50 micrograms per day. The dose should be gradually increased every 2 to 4 weeks according to the response to treatment.
To administer a specific dose, use the enclosed oral syringe - see instructions below.
The syringe can be used to measure the dose by drawing the liquid up to the appropriate mark on the syringe. For example, if the dose for the patient is 50 micrograms per day, the volume will be 2 x 5 mL (a total of 10 mL).

For a strength of 25 micrograms/5 mL - 2 x 5 mL (a total of 10 mL)

For a strength of 50 micrograms/5 mL - 5 mL

For a strength of 100 micrograms/5 mL - 2.5 mL

How to use the oral syringe:

• 1. Shake the bottle well, making sure the cap is tightly closed on the bottle.
• 2. Remove the cap. Note: Keep the cap nearby to close the bottle after each use.
• 3. Insert the plastic adapter into the neck of the bottle. Note: The adapter must always remain in the bottle.
• 4. Take the syringe and check that the plunger is fully down.

• 5. Hold the bottle upright and firmly attach the oral syringe to the plastic adapter.
• 6. Turn the entire bottle with the syringe upside down.
• 7. Slowly pull the plunger to fill the syringe with the medicine. Push the plunger back to the end to remove any large air bubbles that may have become trapped in the oral syringe.
• 8. Then slowly pull the plunger to the volume required to administer the specified dose.
• 9. Turn the entire bottle with the syringe and remove the syringe from the bottle.
• 10. The dose of the medicine can now be swallowed directly from the oral syringe. Make sure the patient is sitting upright. The plunger must be pressed slowly to allow the dose to be swallowed.
• 11. After use, replace the protective cap to prevent access by children, leaving the adapter in place.
• 12. Cleaning: After use, wipe the outside of the syringe with a dry, clean cloth.

Method of administration

Althyxin should be swallowed. Althyxin should be taken on an empty stomach, usually before breakfast.

Duration of treatment

Treatment usually lasts for life in the case of hypothyroidism, non-toxic diffuse goiter or Hashimoto's thyroiditis.

Overdose of Althyxin

In the event of accidental overdose, contact your doctor or go to the emergency room of the nearest hospital immediately. Symptoms of overdose include fever, irregular heartbeat, muscle cramps, headache, restlessness, flushing, sweating or diarrhea. Always take the medicine, container and label with you so that it can be identified.

Missed dose of Althyxin

If you miss a dose, take it as soon as you remember, and take the next dose at the usual time. Do not take a double dose of the medicine to make up for the missed dose. If you miss several doses, inform your doctor at your next scheduled check-up or blood test.

Stopping Althyxin treatment

To be effective, Althyxin should be taken regularly in the doses prescribed by your doctor. Under no circumstances should you change, stop or discontinue the prescribed treatment or medicine without consulting your doctor. The symptoms of the disease may return if you stop treatment or discontinue the medicine too early. The type of these symptoms depends on the underlying disease.
If you have any further questions about taking this medicine, consult your doctor or pharmacist.

4. Possible side effects

Like all medicines, this medicine can cause side effects, although not everybody gets them.
This usually happens when the dose of the medicine is too high.

If you experience any of the following symptoms, stop taking Althyxin and contact your doctor or go to the emergency room of the nearest hospital immediately:

• swelling of the hands, feet, ankles, face, lips, mouth or throat, which may cause difficulty swallowing or breathing;
• hives;
• fainting;
• yellowing of the skin and whites of the eyes, also known as jaundice.

These are very serious side effects. If they occur, you may have a severe allergic reaction to Althyxin. You may need urgent medical attention or hospitalization. All these very serious side effects are very rare.
If you experience any of the following symptoms, inform your doctor:
Fast or irregular heartbeat, palpitations, chest pain, muscle cramps or weakness, headache, restlessness, excitement, hot flashes, circulatory collapse in premature infants with low birth weight (see section 2), sweating, diarrhea, vomiting, fever, menstrual disorders, high intracranial pressure, tremors, insomnia, heat intolerance and excessive weight loss. You may also experience angioedema, rash, hives, itching and swelling.
Very rarely, after taking a single dose of Althyxin that is too high or after taking high doses of this medicine for many years, heart failure may develop, and coma and death have been reported.
If you feel unwell in any way that is not usual, you should consult your doctor as soon as possible.

Additional side effects in children

At the beginning of treatment in children, hair loss may occur, but this is usually temporary and the hair grows back.

Reporting side effects

If you experience any side effects, including any not listed in this leaflet, you should tell your doctor or pharmacist, or nurse. Side effects can be reported directly to the Department of Adverse Reaction Monitoring of Medicinal Products, Medical Devices and Biocidal Products:
Jerozolimskie Avenue 181C, 02-222 Warsaw, tel.: +48 22 49 21 301, fax: +48 22 49 21 309,
website: https://smz.ezdrowie.gov.pl
Side effects can also be reported to the marketing authorization holder or its representative in Poland.
By reporting side effects, you can help provide more information on the safety of this medicine.

5. How to store Althyxin

Keep the medicine out of the sight and reach of children.

Expiry date

The shelf life after opening the bottle is 8 weeks.
Do not use this medicine after the expiry date stated on the label and carton after EXP.
The expiry date refers to the last day of the month stated.

Storage conditions

Do not store above 25°C.
Store in the original packaging to protect from light.
If the appearance or smell of the medicine changes, do not use it. Consult your pharmacist.
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 packaging and other information

What Althyxin contains

• The active substance of Althyxin is levothyroxine sodium.

Althyxin, 25 micrograms/5 mL, oral solution:

Each 5 mL of oral solution contains levothyroxine in an amount equivalent to 25 micrograms of anhydrous levothyroxine sodium.

Althyxin, 50 micrograms/5 mL, oral solution:

Each 5 mL of oral solution contains levothyroxine in an amount equivalent to 50 micrograms of anhydrous levothyroxine sodium.

Althyxin, 100 micrograms/5 mL, oral solution:

Each 5 mL of oral solution contains levothyroxine in an amount equivalent to 100 micrograms of anhydrous levothyroxine sodium.

• The other ingredients are: glycerol, citric acid monohydrate, methyl parahydroxybenzoate sodium, sodium hydroxide and purified water.

What Althyxin looks like and contents of the packaging

Althyxin is a clear, colorless liquid. Each glass bottle (type III) with a HDPE/PP closure and a child-resistant cap and a tamper-evident seal contains 75 mL or 100 mL of levothyroxine sodium in the form of an oral solution. Althyxin is available in packs containing one glass bottle of 75 mL or 100 mL of oral solution and two glass bottles of 75 mL of oral solution.
A 5 mL oral syringe with a scale in 0.1 mL increments is also included to facilitate dosing.
Not all pack sizes may be marketed.

Marketing authorization holder

Zentiva, k.s.,
U kabelovny 130
Dolní Měcholupy
102 37 Prague 10
Czech Republic
(marketing authorization holder's logo)

Manufacturer

Galenica Pharmaceutical Industry S.A.
3rd km Old National Road Chalkida-Athens
34100 Glifa Chalkida Eubia
Greece

This medicine is authorized in the Member States of the European Economic Area under the following names:

Germany
L-Thyroxin Zentiva
Poland
Althyxin
Portugal
Alverox

For more information about this medicine, contact the representative of the marketing authorization holder in Poland:

Zentiva Poland Sp. z o.o.
Bonifraterska Street 17
00-203 Warsaw
tel.: +48 22 375 92 00
Date of last revision of the leaflet:February 2023