Euthyrox 75mcg (100 Tab)

EUTHYROX 75MCG (100 TAB) by MERCK LIMITED

Name

• Common Name: Levothyroxine sodium
• Brand Name: Euthyrox 75mcg

Composition

• Active Ingredient: Each tablet contains 75 micrograms (mcg) of Levothyroxine sodium.
• Inactive Ingredients: Corn starch, croscarmellose sodium, gelatine, magnesium stearate, citric acid, and mannitol.

Uses

Euthyrox 75mcg is primarily prescribed for:

• Hypothyroidism: Replacement therapy for an underactive thyroid gland (hypothyroidism), where the thyroid does not produce sufficient thyroid hormones.
• Goitre: Treatment of benign euthyroid goitre and prophylaxis of relapse after surgery for euthyroid goitre.
• Thyroid Cancer: As suppression therapy in thyrotropin-dependent well-differentiated thyroid cancer, often as an adjunct to surgery and radioiodine therapy.
• Hyperthyroidism: Concomitant therapy during anti-thyroid medicinal treatment to balance thyroid hormone levels.

Dosage and Administration

• Euthyrox 75mcg is taken orally as a single daily dose.
• It is generally recommended to take the tablet on an empty stomach, 30 minutes to 1 hour before breakfast, with a full glass of water.
• Consistency in timing and dosage is crucial for maintaining stable hormone levels.
• The dosage is highly individualized, determined by age, body weight, medical condition, lab test results, and response to treatment.
• For infants or children who cannot swallow whole tablets, the tablet can be crushed and mixed with 1 to 2 teaspoons (5 to 10 milliliters) of water, breast milk, or non-soy-based formula, and administered immediately. Do not prepare a supply in advance or mix with soy infant formula.
• The full therapeutic effect may take 4 to 6 weeks to be attained.
• Thyroid replacement therapy is usually a lifelong treatment.

Side Effects

Common side effects, often indicative of a dose that is too high, include:

• Headache
• Weight loss
• Insomnia (difficulty in sleeping)
• Nervousness, irritability, mood swings
• Increased sweating, sensitivity to heat (heat intolerance)
• Diarrhea, stomach cramps
• Shaking (tremor)
• Fast, pounding, or irregular heartbeat (palpitations, arrhythmia)
• Shortness of breath
• Muscle weakness, muscle cramps
• Changes in the menstrual cycle
• Temporary hair loss (especially in children)

Serious side effects, though less common, require immediate medical attention:

• Severe chest pain, heart attack
• Seizures
• Confusion
• Signs of allergic reaction such as swelling of the face, tongue, hands, ankles, or feet; hives; or trouble breathing.
• Bone pain or easily broken bones (increased risk of osteoporosis with high doses).

Precautions

• Medical Conditions: Inform your doctor about your medical history, especially if you have heart disease (e.g., coronary artery disease, high blood pressure, irregular heartbeat), diabetes, adrenal gland insufficiency, pituitary insufficiency, or an untreated overactive thyroid (thyrotoxicosis).
• Pregnancy and Breastfeeding: Dosage adjustments may be necessary during pregnancy, and regular monitoring of thyroid levels is advised. Levothyroxine passes into breast milk but is generally considered unlikely to harm a nursing infant.
• Drug Interactions: Euthyrox can interact with other medications, including antidiabetic drugs (requiring dose adjustments), blood thinners (e.g., coumarin derivatives), certain antidepressants, ion exchange resins, proton pump inhibitors, and some tyrosine kinase inhibitors.
• Food Interactions: Certain foods and supplements can interfere with levothyroxine absorption. Avoid taking calcium supplements, iron preparations, antacids (containing aluminum or magnesium), soy products, grapefruit, high-fiber foods, walnuts, cottonseed meal, cabbage, or cauliflower within at least 4 hours of taking Euthyrox.
• Monitoring: Regular blood tests (e.g., TSH, T4 levels) are essential to monitor the effectiveness of therapy and ensure appropriate dosing.
• Weight Loss: Euthyrox should not be used for weight loss in individuals with normal thyroid function, as high doses can lead to serious, potentially fatal side effects.
• Do not stop taking the medication abruptly without consulting your doctor.

Storage

• Store Euthyrox 75mcg tablets below 25°C or not above 30°C.
• Keep the tablets in their original outer carton to protect them from light.
• Do not remove individual tablets from the blister packaging until immediately prior to use.
• Keep out of the sight and reach of children.
• The potency of levothyroxine can be significantly affected by external factors like light, oxygen, and moisture, making proper storage vital for consistent efficacy.

What is Euthyrox 75mcg used for?

Euthyrox 75mcg is a medication primarily used to treat hypothyroidism, a condition where the thyroid gland does not produce enough thyroid hormones. It replaces the missing thyroid hormone (levothyroxine sodium) to restore normal levels in the body, which helps alleviate symptoms like fatigue, weight gain, and depression. It is also used to treat benign euthyroid goiter (enlarged thyroid gland), prevent its recurrence after surgery, and as an adjunct to surgery and radioiodine therapy in managing certain types of thyroid cancer.

How does Euthyrox 75mcg work?

Euthyrox 75mcg contains levothyroxine sodium, a synthetic form of the natural thyroid hormone thyroxine (T4). Once absorbed, it is converted into triiodothyronine (T3) in various organs. T3 then binds to specific receptors within cell nuclei, activating gene transcription and protein synthesis. This process regulates the body's metabolism, energy levels, growth, and development, effectively replacing the deficient natural thyroid hormone.

What is the usual dosage for Euthyrox 75mcg?

The dosage of Euthyrox 75mcg is highly individualized and determined by your doctor based on factors such as your age, weight, medical condition, thyroid hormone levels (TSH), and response to treatment. It is typically taken once daily, in the morning, on an empty stomach, at least 30 to 60 minutes before breakfast and other medications, with a full glass of water. For some, a consistent evening dose, at least three to four hours after the last meal, might be an option. The full therapeutic effect of a given dose may take 4 to 6 weeks to be observed.

What are the possible side effects of Euthyrox 75mcg?

Side effects of Euthyrox 75mcg usually indicate that the dosage is too high, leading to symptoms of hyperthyroidism (overactive thyroid). Common side effects can include headache, insomnia, weight loss, increased heart rate or palpitations, increased sweating, sensitivity to heat, nervousness, irritability, emotional lability, diarrhea, and tremors. Less common but serious side effects can include chest pain, shortness of breath, severe headaches, dizziness, or allergic reactions like rash or swelling. If you experience any severe or persistent side effects, contact your doctor immediately.

Is Euthyrox 75mcg safe during pregnancy or breastfeeding?

Yes, Euthyrox 75mcg is generally considered safe and essential to continue taking during pregnancy and breastfeeding. Untreated hypothyroidism during pregnancy can pose risks to both the mother and the fetus. Your dosage requirements may even increase during pregnancy, so your doctor will likely monitor your TSH levels during each trimester and adjust the dose as needed. Levothyroxine is secreted into breast milk, but the concentrations are usually not sufficient to cause hyperthyroidism or suppress TSH secretion in the nursing infant.

Can Euthyrox 75mcg be taken with other medications?

Euthyrox 75mcg can interact with several other medications and substances, affecting its absorption and effectiveness. It's crucial to inform your doctor about all medications, supplements, and herbal products you are taking. Some common interactions include:

• Antacids, iron-containing drugs, calcium salts, and sucralfate: These can decrease the absorption of levothyroxine. Take Euthyrox at least 2-4 hours before or after these.
• Proton Pump Inhibitors (PPIs): These can decrease thyroid hormone absorption due to increased intragastric pH. Your doctor may monitor your thyroid function and adjust the Euthyrox dose.
• Soy products and high-fiber foods: These can lower levothyroxine uptake from the intestine. Dosage adjustment may be necessary if you consume these regularly.
• Antidiabetic drugs: Levothyroxine may reduce the effect of antidiabetics, requiring frequent blood glucose monitoring and potential adjustment of antidiabetic medication.
• Coumarin derivatives (blood thinners): Euthyrox can intensify the effect of anticoagulants, increasing the risk of bleeding. Close monitoring of blood clotting parameters and anticoagulant dose adjustment may be necessary.
• Estrogen-containing contraceptives or hormone replacement therapy: Women on these may have an increased need for levothyroxine.

What precautions should be taken while taking Euthyrox 75mcg?

• Do not use for weight reduction: Euthyrox should not be used for weight loss in individuals with normal thyroid function, as it is ineffective and large doses can cause serious, life-threatening side effects, especially when combined with diet pills.
• Monitor thyroid levels: Regular monitoring of thyroid-stimulating hormone (TSH) and/or T4 levels is essential to ensure the correct dosage and effectiveness of therapy.
• Pre-existing conditions: Inform your doctor if you have a history of heart disease (e.g., coronary artery disease, irregular heartbeat), high blood pressure, diabetes, or adrenal gland problems, as these may require special caution and dose adjustments.
• Hypersensitivity: Do not take Euthyrox if you have untreated adrenal insufficiency, untreated pituitary insufficiency, untreated thyrotoxicosis, or hypersensitivity to any of its ingredients.

What happens if a dose of Euthyrox 75mcg is missed?

If you miss a dose of Euthyrox 75mcg, take it as soon as you remember. If it is almost time for your next scheduled dose, skip the missed dose and continue with your regular dosing schedule. Due to levothyroxine's long half-life (approximately 7 days), missing one dose typically does not cause significant problems. Some experts suggest that it is generally safe to take two levothyroxine tablets the day after missing one to "catch up," but this should not be done regularly or without consulting your doctor. Do not double doses to make up for multiple missed doses.

How should Euthyrox 75mcg be stored?

Euthyrox 75mcg tablets should be stored at temperatures not exceeding 30°C. Keep the container in its outer carton to protect it from light and moisture. Keep the medication out of reach of children.