Levothyroxine, the active substance in EUTHYROX, is a synthetic thyroid hormone for the treatment of diseases and dysfunctions of the thyroid gland. When the thyroid gland does not produce enough thyroxine (a condition known as hypothyroidism), many of the body’s functions slow down. EUTHYROX is used to replace the thyroxine that your thyroid gland cannot produce and prevent the symptoms of hypothyroidism. Before starting your treatment, your doctor will carry out a blood test to work out how much levothyroxine you need.
1. What EUTHYROX is and what it is used for
2. What you need to know before you take EUTHYROX
Do not use EUTHYROX If you have any of the following:
- Allergy (hypersensitivity) to the active substance or to any of the other ingredients of EUTHYROX (listed in section 6)
- Untreated dysfunction of the adrenal gland, pituitary gland or excessive overproduction of thyroid hormones (thyrotoxicosis)
- Acute heart disease (myocardial infarction or heart inflammation)
Do not take Euthyrox together with antithyroid medicines if you are pregnant.
Warnings and precautions
Talk to your doctor or pharmacist before taking Euthyrox if you have any of the following heart diseases:
- insufficient blood flow in the blood vessels of the heart (angina pectoris)
- heart failure
- rapid and irregular heartbeat
- high blood pressure
- fatty deposits in your arteries (arteriosclerosis)
Your doctor will investigate if you have a dysfunction of the adrenal or pituitary gland or a dysfunction of the thyroid gland with uncontrolled overproduction of thyroid hormones (thyroid autonomy), because this must be medically controlled before you start taking EUTHYROX. Thyroid imbalance may occur if you need to change your medication to another levothyroxine containing product. Talk to your doctor if you have any questions about changing your medication. A close monitoring (clinical and biological) is required during the transition period. You should tell your doctor if you get any side effects as this may indicate that your dose needs to be adjusted up or down.
Speak to your doctor:
- if you are in the menopause or post-menopausal; your doctor may need to check your thyroid function regularly because of the risk of osteoporosis
- before you start or stop taking orlistat, or change the treatment with orlistat (medication to treat obesity; you may need closer monitoring and dose adjustment)
- if you experience signs of psychotic disorders (you may need closer monitoring and dose adjustment)
Thyroid hormones should not be used for weight reduction. Intake of thyroid hormones will not reduce your weight, if your thyroid hormone level is in a normal range. Serious or even life-threatening side effects may occur if you increase the dose without special advice from your doctor. High doses of thyroid hormones should not be taken together with certain medicines for weight reduction, such as amfepramone, cathine and phenylpropanolamine, as the risk of serious or even life-threatening side effects may increase.
3. How to take EUTHYROX
Do not share medicines prescribed for you with any other person. Always take EUTHYROX exactly as your doctor has told you. Check with your doctor, if you are not sure. Your doctor will determine your individual dose based on examinations and as well as on laboratory tests. If your baby is born with hypothyroidism your doctor may recommend starting with a higher dose because a rapid replacement is important. The initial recommended dosage is 10 to 15 micrograms per kg body weight for the first 3 months. Thereafter, your doctor will adjust the dose individually.
Take a single daily dose on an empty stomach in the morning (at least half an hour before breakfast), preferably with a little liquid, for example with half a glass of water. Infants may receive the entire daily dose of EUTHYROX at least half an hour before the first meal of the day. Immediately before use, crush the tablet and mix it with some water and give it to the child with some more liquid. Always prepare the mixture freshly. Duration of treatment may vary depending on the condition for which you use EUTHYROX. Your doctor will tell you how long your treatment with EUTHYROX will last. Most patients need to take EUTHYROX for their lifetime.
If you have the impression that the effect of EUTHYROX is too strong or too weak, tell your doctor or pharmacist.
If you take more EUTHYROX than you should If you have taken a higher dose than prescribed, you may experience symptoms such as rapid heartbeat, anxiety, agitation, tremor or unintended jerky movements. In patients with a disorder affecting the neurological system such as epilepsy, seizures may occur. If any of this happen contact your doctor. In the event of overdosage, consult your doctor or pharmacist. If neither is available, contact the nearest hospital or poison centre.
If you forget to take EUTHYROX Do not take a double dose to make up for a forgotten tablet but take the normal dose the following day. If you have any further questions on the use of EUTHYROX, ask your doctor or pharmacist. If you stop taking EUTHYROX These tablets are for long term use. You may need to take them for the rest of your life. Do not stop taking the tablets unless your doctor has told you to do so. If you have any further questions on the use of this medicine, ask your doctor or pharmacist.
4. Possible side effects
EUTHYROX can cause side effects. Not all side effects reported for EUTHYROX are included in this leaflet. Should your general health worsen or if you experience any untoward effects while taking EUTHYROX, please consult your health care provider for advice. If any of the following happens, stop taking EUTHYROX and tell your doctor immediately or go to the casualty department at your nearest hospital: If you have any of these signs of an allergic reaction to EUTHYROX: difficulty breathing, swelling of your face, lips, tongue or throat. These are all very serious side effects. If you have them, you may have had a serious reaction to EUTHYROX. You may need urgent medical attention or hospitalisation.
You may experience one or more of the following side effects: Irregular or rapid heartbeat, chest pain, headache, muscle weakness or cramps, flushing (warmth and redness of the face), fever, vomiting, disorders of menstruation, pseudotumor cerebri (increased pressure in the head with eye swelling), trembling, restlessness, sleep disturbances, sweating, weight loss, diarrhoea. If you experience any of these side effects, contact your doctor. Your doctor may decide to reduce the daily dose until the side effects have disappeared.
If you notice any side effects not listed in this leaflet, tell your doctor or pharmacist.
Reporting of side effects
If you get side effects, talk to your doctor, pharmacist. You can also report side effects to the South African Health Products Regulatory Authority (SAHPRA) via the “6.04 Adverse Drug Reaction Reporting Form”, found online under SAHPRA’s publications: https://www.sahpra.org.za/Publications/Index/8. By reporting side effects, you can help provide more information on the safety of EUTHYROX.
5. How to store EUTHYROX
Store all medicines out of reach of children. Store at or below 30 °C. Keep the blisters in the outer carton, in order to protect from light. Do not use EUTHYROX after the expiry date, which is stated on the blister and the carton after EXP. The expiry date refers to the last day of that month. Return all unused medicine to your pharmacist. Do not dispose of unused medicine in drains or sewerage systems (e.g., toilets).