Euthyrox 0.2mg (200mcg) 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 exert their metabolic effects through control of DNA transcription and protein synthesis. Thyroid hormones are involved in normal metabolism, growth, and development, and regulate carbohydrate, protein, and lipid metabolism.

Urgent Side Effects: Seek Medical Help Right Away

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

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
+ 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 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, consult 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 continuous treatment, do not allow your supply of this medication to run out. Please note that it may take several weeks to experience the full effects of this medication.

Special Considerations

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

If you are taking biotin or a product containing biotin, stop taking it 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 osteoporosis (weak bones), particularly after menopause. Discuss your individual risk factors with your doctor, who can help determine if you are at higher risk.

This medication may also affect fertility, potentially making it more difficult to become pregnant or father a child. If you plan to conceive, consult your doctor before starting treatment.

Age-Related Considerations

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

Pregnancy and Breastfeeding

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

Pediatric Patients

If you are giving this medication to a child and their weight changes, consult your doctor, as the dosage may need to be adjusted. Never give your child more of this medication than prescribed, as this may increase the risk of severe side effects.

In some cases, this medication may affect growth in children and teenagers. Regular growth checks may be necessary, so be sure to discuss this with your doctor.

• Amiodarone (can cause hypo- or hyperthyroidism, alters T4 to T3 conversion)
• Antacids (aluminum, magnesium, calcium) - decrease absorption
• Bile acid sequestrants (cholestyramine, colestipol) - decrease absorption
• Cation exchange resins (sodium polystyrene sulfonate) - decrease absorption
• Iron supplements - decrease absorption
• Calcium supplements - decrease absorption
• Sucralfate - decrease absorption
• Proton pump inhibitors (PPIs) - may decrease absorption due to increased gastric pH
• Soy products - decrease absorption
• Orlistat - may decrease absorption
• Tyrosine kinase inhibitors (e.g., imatinib, sunitinib) - may increase levothyroxine requirements
• Estrogens (oral) - increase TBG, increasing levothyroxine requirements
• Androgens - decrease TBG, decreasing levothyroxine requirements
• Glucocorticoids - may decrease TBG, alter T4 to T3 conversion
• Phenytoin, Carbamazepine, Rifampin, Phenobarbital (CYP inducers) - increase levothyroxine metabolism, increasing requirements
• Warfarin - enhances anticoagulant effect (monitor INR)

• Beta-blockers - may decrease T4 to T3 conversion
• Digoxin - thyroid hormones affect digoxin levels
• Antidiabetic agents - may increase blood glucose, requiring adjustment of antidiabetic therapy
• SSRIs - may affect thyroid function tests, but clinical significance often low
• Dietary fiber - may decrease absorption

• Coffee - may decrease absorption if taken concurrently

• Fatigue
• Weight changes (gain or difficulty losing)
• Cold intolerance
• Constipation
• Dry skin
• Hair loss
• Bradycardia
• Depression or mood changes
• Muscle aches or weakness
• Memory impairment or difficulty concentrating

Levothyroxine is Category A. Thyroid hormone requirements often increase during pregnancy (by 25-50% or more) due to increased TBG and fetal needs. Close monitoring of TSH is essential, typically every 4-6 weeks, with dose adjustments to maintain TSH in the trimester-specific target range (e.g., 0.1-2.5 mIU/L in 1st trimester). Untreated maternal hypothyroidism can lead to adverse fetal outcomes.

Levothyroxine is compatible with breastfeeding (L1). Only small amounts are excreted into breast milk, which are not clinically significant and do not affect infant thyroid function. Maternal thyroid hormone requirements typically return to pre-pregnancy levels postpartum, requiring dose adjustment.

Dosing is weight-based and higher per kg than in adults, especially in infants and young children, due to rapid growth and higher metabolic rates. Regular monitoring of TSH and Free T4 is crucial to ensure proper growth and neurocognitive development. Treatment is lifelong for congenital hypothyroidism.

Lower starting doses (e.g., 12.5-25 mcg/day) are often recommended, especially in patients with cardiovascular disease, due to increased sensitivity to thyroid hormones and potential for cardiac adverse effects. Dose adjustments should be made in smaller increments and less frequently. Close monitoring for cardiac symptoms is important.

• Levothyroxine is a narrow therapeutic index drug; consistency in brand/generic and administration is important.
• Take consistently at the same time each day, preferably in the morning on an empty stomach, 30-60 minutes before food or other medications.
• Many medications and foods can interfere with absorption; separate administration times.
• TSH is the primary monitoring parameter; recheck 4-6 weeks after any dose change.
• Patients may require higher doses during pregnancy.
• Symptoms of hypothyroidism resolve gradually over weeks to months.
• Do not use for weight loss in euthyroid individuals due to risk of serious adverse effects.

• Liothyronine (T3) - used in specific cases like myxedema coma or for short-term TSH suppression before radioactive iodine, but not for routine long-term hypothyroidism due to shorter half-life and fluctuating levels.

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 emergency medical attention. When seeking help, be prepared to provide details about the medication taken, the amount, and the time it occurred.