Euthyrox is a medication in pill prescribed when your thyroid gland does not produce enough hormones. It is also used as a substitute for natural hormones after thyroid removal surgery.

Active substance

The active substance of the preparation is levothyroxine sodium, a synthetic form of the thyroid hormone. The thyroid hormone regulates your body energy and metabolism. Depending on your needs, the doctor selects the appropriate drug dosage (25-200μg). 

Indications for use

Euthyrox has wide applications. According to the leaflet, doctors prescribe Euthyrox for:

• patients with hypothyroidism, including replacement therapy
• replacement therapy for patients after the thyroid removal surgery 
• treatment of indolent thyroid goiter, and also when it is necessary to prevent recurrence of goiter in patients after surgical removal of thyroid goiter 
• treatment of thyroid cancer as part of suppressive therapy.

Contradictions

Do not take Euthyrox if you:

• are hypersensitive to any component of the drug
• have untreated adrenal insufficiency, pituitary insufficiency, or hyperthyroidism
• have just had a heart attack
• are undergoing myocarditis
• are undergoing acute inflammation of all layers of the heart.

Side effects

As with all drugs, Euthyrox can adversely affect the human body if you do not use the drug as prescribed and do not perform tests. In addition, if you take more Euthyrox pills than your body needs, symptoms characteristic of hyperthyroidism may appear (check section Overdosing). 

Furthermore, if you increase the doses of the drug too rapidly at the beginning of the treatment, the following symptoms may occur:

• heart rhythm disturbances
• tachycardia
• palpitations
• angina pectoris
• menstrual disorders
• restlessness
• gastro-intestinal complaints.

If such symptoms occur after taking Euthyrox, your doctor should reduce the dose or discontinue treatment for some time. Euthyrox therapies can be resumed once the symptoms have disappeared.

Dosage

Your endocrinologist will determine the exact dosage based on an assessment of your blood test results, individual performance, and the disease.

It is recommended to start the treatment with the smallest possible doses and, if necessary, to increase the quantity every 2-4 weeks after follow-up thyrotropin (a hormone stimulating thyroid activity) tests. Infants can take the drug after dissolving it in a small amount of water.

Eythyrox is absorbed in the gut, and certain types of food like a diary or calcium-rich products may negatively affect its absorption. That is why the medication should be taken half an hour before your first meal in the morning, with a small amount of water. Try to take medication every day at the same hour.

Overdosing

Levothyroxine is a hormone that should be administered with care, strictly following the doctors’ prescription.

The doctor assesses an overdose of Euthyrox based on the patient’s blood tests and T3 hormone levels. Patients who have experienced an overdose had a significantly increased metabolic rate in the body. Although, in an overdose situation, the course of action depends on the patient’s condition, most often, treatment should be discontinued and only resumed after investigations and consultation with the doctor.
In case of overdose, the following side effects may occur:

• hyperthyroidism, 
• psychotic disorders 
• and, in individual cases, seizures and symptoms characteristic of hyperthyroidism.

A lethal dose of Euthyrox has been observed in individual cases, described as sudden death resulting from cardiac disorders in patients who have abused the drug for many years.

Interactions with alcohol

There is insufficient information on whether hypothyroidism drugs such as Euthyrox interact with alcohol. However, particular care should be taken when consuming alcohol during therapy.

Euthyrox in pregnancy

Medical researchers consider Euthyrox safe in pregnancy and during breastfeeding.

Euthyrox thyroid tablets can be taken by pregnant women, as the need for the drug may even be higher during pregnancy. Women should monitor their TSH levels during each trimester. After delivery, serum TSH concentrations should reach typical values within 6-8 weeks. Only significantly elevated doses can adversely affect the child’s development during pregnancy and after birth.

Euthyrox and breastfeeding

Levothyroxine penetrates breast milk. However, its concentration in the milk is so low during therapy with therapeutic doses that do not affect the baby. Therefore, the lowest effective doses taken by the woman should only affect stabilisation of maternal TSH secretion without the development of hyperthyroidism or inhibition of TSH secretion in the child.

Precautions

If you have untreated conditions, talk to your doctor. You should be checked for coronary insufficiency, angina pectoris, vascular atherosclerosis, hypopituitarism, hypertension, autonomic thyroid function, a thyroid disorder called thyrotoxicosis, and adrenal insufficiency. These diseases should be excluded or treated.

If you are taking other medicines, tell your doctor. He must exclude potential risky interactions.

During pregnancy and breastfeeding, hormonal treatment should be continued. In many cases, during pregnancy, doctors need to prescribe higher Euthyrox doses.

Disclaimer

Before use, read the leaflet carefully or consult your doctor or pharmacist, as any medicine used inappropriately poses a risk to your life or health.

Martyna Piotrowska

Resources:

Euthyrox | co to jest, dawkowanie, skutki uboczne leku (medicover.pl)

Euthyrox – wskazania, skład, przeciwwskazania, dawkowanie (medonet.pl)

https://exactlyhowlong.com/how-long-after-taking-euthyrox-can-i-eat-and-why/

Euthyrox: Side Effects, Uses & Dosage – Drugs.com

Levothyroxine and breastfeeding. Are they compatible? (e-lactancia.org)