Euthyrox 0.137mg (137mcg) Tab

Levothyroxine (T4) is a synthetic form of the natural thyroid hormone, thyroxine. It is converted to its active metabolite, liothyronine (T3), in peripheral tissues. T3 and T4 act on thyroid hormone receptors in the cell nucleus to regulate gene expression, controlling metabolism, growth, and development.

Serious Side Effects: Seek Medical Help Right Away

Although rare, some people may experience severe and potentially life-threatening side effects while taking this medication. If you notice any of the following symptoms, contact your doctor immediately or seek emergency medical attention:

Signs of an allergic reaction, such as:
+ Rash
+ Hives
+ Itching
+ Red, swollen, blistered, or peeling skin with or without fever
+ Wheezing
+ Tightness in the chest or throat
+ Trouble breathing, swallowing, or talking
+ Unusual hoarseness
+ Swelling of the mouth, face, lips, tongue, or throat
Signs of high blood pressure, including:
+ Severe headache or dizziness
+ Passing out or loss of consciousness
+ Changes in eyesight
Chest pain or pressure
Fast or abnormal heartbeat
Shortness of breath
Sudden weight gain or swelling in the arms or legs
Headache
Feeling tired or weak
Changes in appetite
Unintentional weight changes
Diarrhea, stomach cramps, or vomiting
Mood changes, such as feeling irritable, nervous, excitable, anxious, or restless
Shakiness
Trouble sleeping
Sensitivity to heat
Excessive sweating
Fever
Muscle cramps
Muscle weakness
Flushing
Bone pain
Changes in menstrual periods (in women)
In children: hip or knee pain, or a limp
In infants: changes in the shape of the head and face

Other Possible Side Effects

Like all medications, this drug can cause side effects. While many people may not experience any side effects or only minor ones, it's essential to discuss any concerns with your doctor. If you experience any of the following side effects or any other symptoms that bother you or do not go away, contact your doctor:

* Hair loss (usually temporary and resolves on its own within the first few months of treatment)

Reporting Side Effects

This is not an exhaustive list of possible side effects. If you have questions or concerns about side effects, contact your doctor. You can also report side effects to the FDA at 1-800-332-1088 or online at https://www.fda.gov/medwatch.

Before Taking This Medication: Important Information to Share with Your Doctor

It is essential to inform your doctor about the following:

Any allergies you have, including allergies to this medication, its components, or other substances, such as foods or drugs. Be sure to describe the allergic reaction you experienced, including any symptoms that occurred.
Certain health conditions, including:
+ An overactive thyroid gland
+ A weak adrenal gland
+ Difficulty swallowing
This list is not exhaustive, and it is crucial to discuss all your health problems with your doctor.

Additionally, provide your doctor and pharmacist with a comprehensive list of all the medications you are taking, including:
Prescription medications
Over-the-counter (OTC) medications
Natural products
* Vitamins

It is vital to verify that it is safe to take this medication with all your other medications and health conditions. Never start, stop, or change the dose of any medication without first consulting your doctor.

Important Information for All Patients Taking This Medication

It is essential to inform all your healthcare providers, including doctors, nurses, pharmacists, and dentists, that you are taking this medication. To ensure uninterrupted treatment, do not allow your supply of this medication to run out. You may not experience the full effects of this medication for several weeks.

If you have diabetes (high blood sugar), consult with your doctor, as this medication may affect your blood sugar control. Your doctor may need to adjust your diabetes medications. Monitor your blood sugar levels as directed by your doctor and undergo regular blood tests as advised.

When taking biotin or products containing biotin, discontinue use at least 2 days before having your thyroid levels checked to ensure accurate test results.

Potential Risks and Side Effects

High doses of this medication may increase the risk of developing weak bones (osteoporosis), particularly after menopause. Discuss your risk factors with your doctor, who can help determine if you are at higher risk.

This medication may also affect fertility, potentially leading to difficulties in getting pregnant or fathering a child. If you plan to conceive, consult with your doctor before starting treatment.

If you are 65 or older, use this medication with caution, as you may be more susceptible to side effects.

Pregnancy, Breastfeeding, and Pediatric Use

If you are pregnant, plan to become pregnant, or are breastfeeding, inform your doctor to discuss the benefits and risks of this medication to you and your baby.

When administering this medication to children, monitor their weight changes and consult with your doctor, as the dosage may need to be adjusted. Never exceed the recommended dose, as this may increase the risk of severe side effects. In some cases, this medication may affect growth in children and teenagers, requiring regular growth checks. Consult with your doctor to discuss any concerns.

• Amiodarone (can cause hypo- or hyperthyroidism, alter T4/T3 conversion)
• Warfarin (may increase anticoagulant effect)
• Antidiabetic agents (may increase insulin/oral hypoglycemic requirements)
• Ion exchange resins (e.g., Cholestyramine, Colestipol, Sevelamer, Patiromer - reduce absorption of levothyroxine)
• Sucralfate (reduces absorption)
• Proton pump inhibitors (e.g., Omeprazole, Pantoprazole - may reduce absorption)
• Iron supplements (reduce absorption)
• Calcium supplements (reduce absorption)
• Aluminum-containing antacids (reduce absorption)

• Estrogens (increase TBG, may increase levothyroxine requirement)
• Androgens (decrease TBG, may decrease levothyroxine requirement)
• Glucocorticoids (may inhibit TSH secretion and T4 to T3 conversion)
• Beta-blockers (may decrease T4 to T3 conversion)
• Phenytoin, Carbamazepine, Rifampin (increase levothyroxine metabolism)
• Sertraline (may increase levothyroxine requirement)
• Imatinib, Sunitinib (may increase levothyroxine requirement)
• Orlistat (may reduce absorption)

• Dietary fiber (may reduce absorption)

• Hypothyroidism: Fatigue, weight gain, constipation, cold intolerance, dry skin, hair loss, bradycardia, depression, muscle aches, menstrual irregularities.
• Hyperthyroidism (overdose/over-treatment): Palpitations, tachycardia, nervousness, tremor, insomnia, weight loss, heat intolerance, diarrhea, sweating, chest pain, shortness of breath.

Levothyroxine is safe and essential during pregnancy. Thyroid hormone requirements often increase during pregnancy (by 25-50% or more) due to increased TBG, placental deiodination, and fetal thyroid hormone needs. Close monitoring of TSH is crucial.

Levothyroxine is compatible with breastfeeding. Only small amounts are excreted into breast milk, which are not clinically significant to the infant.

Dosing is weight-based and higher per kg than in adults, especially in infants, due to higher metabolic rates and rapid growth. Regular monitoring of TSH and Free T4 is critical to ensure proper growth and neurodevelopment. Crushing tablets and mixing with a small amount of water or breast milk/formula for administration is common.

Lower initial doses are typically recommended due to increased sensitivity to thyroid hormones and higher prevalence of underlying cardiovascular disease. Gradual titration is important to avoid cardiac adverse effects. Monitor TSH and clinical response closely.

• Consistency is key: Take levothyroxine at the same time every day, preferably in the morning on an empty stomach, 30-60 minutes before food or other medications.
• Avoid taking with calcium, iron, antacids, or bile acid sequestrants; separate by at least 4 hours.
• Do not switch between different brands or generic formulations without consulting your healthcare provider, as bioavailability can vary, potentially requiring dose adjustment.
• Full therapeutic effect may take 4-6 weeks to be observed, and TSH levels should be rechecked at this time.
• Patients with pre-existing cardiovascular disease should start with lower doses and titrate slowly to avoid exacerbation of cardiac symptoms.
• Symptoms of over-treatment (hyperthyroidism) or under-treatment (hypothyroidism) should be reported to the healthcare provider immediately.

• Liothyronine (T3) - used in specific cases, e.g., myxedema coma, or for short-term TSH suppression.
• Desiccated Thyroid Extract (DTE) - derived from porcine thyroid glands, contains both T4 and T3.

If your symptoms or health issues persist or worsen, it's essential to contact your doctor for further guidance. To ensure your safety, never share your medication with others or take someone else's medication. Some medications may come with an additional patient information leaflet, so be sure to check with your pharmacist for more information. If you have any questions or concerns about your medication, don't hesitate to reach out to your doctor, nurse, pharmacist, or other healthcare provider. In the event of a suspected overdose, immediately call your local poison control center or seek medical attention. When seeking help, be prepared to provide details about the medication taken, the amount, and the time it occurred.