Synroid
Form: Tablet
Strength: 50mcg
Generic Name: Levothyroxine Sodium
Company: Beximco Pharmaceuticals Ltd.
MRP:৳ 1.6 (Box=100)
Per Piece: ৳ 0.02
Is Antibiotic: No
Indications
Synroid is used to replace thyroid hormone in conditions like hypothyroidism. Synroid should not be used for temporary hypothyroidism during recovery from subacute thyroiditis. Synroid is also used to lower thyroid-stimulating hormone (TSH) levels in cases of goiters, thyroid nodules, and after treatments for thyroid cancer. Synroid helps reduce the goitrogenic effects of other drugs like Lithium and is used in diagnostic tests for thyroid suppression.
Pharmacology
This tablet contains synthetic Levothyroxine (also known as Thyroxine or T4), which is identical to the hormone naturally produced by the thyroid gland. Around 30% of T4 is converted to a more active form called Triiodothyronine (T3) in the body. T4 is mostly carried in the blood by a protein called Thyroxine Binding Globulin (TBG), which protects Synroid from being broken down too quickly. The half-life of T4 in the body is about 6 to 7 days, but this can change depending on conditions like hyperthyroidism or hypothyroidism. The liver is where T4 is broken down and excreted in the urine. Since T4 has a long half-life, taking Synroid once a day can keep steady levels of the active T3 hormone in the body.
Dosage & Administration
Adult dose: Start with 25-50 mcg/day, with gradual increases every 6-8 weeks if needed. The dose can be adjusted by 12.5-25 mcg until the patient reaches normal TSH levels. In severe cases of hypothyroidism, start with 12.5-25 mcg/day and increase by 25 mcg every 2-4 weeks until TSH levels normalize. In cases of secondary or tertiary hypothyroidism, the dose should be adjusted until the free T4 levels are within the normal range.
For patients over 50 years or with heart problems: The recommended dose is 1.7 mcg/kg/day.
Pediatric Dosage (Newborns): Start with 10-15 mcg/kg/day, with adjustments based on clinical response.
Pediatric Dosage (Children): In children, the dose starts at 25 mcg/day, increasing every 2-4 weeks until the desired effect is achieved. The dose should be adjusted based on age and clinical response.
Interaction
Taking Levothyroxine with certain antidepressants may increase both the effects and side effects of both drugs, leading to a higher risk of heart problems and nervous system side effects. Levothyroxine can also affect the dosage of diabetes medications, and insulin doses may need to be adjusted. Synroid may reduce the effectiveness of digitalis glycosides in hyperthyroidism or when moving to a normal thyroid state.
Contraindications
Synroid is not suitable for patients with untreated hyperthyroidism, acute heart attacks, or uncorrected adrenal failure.
Side Effects
Side effects usually happen if the dose is too high and can include fatigue, increased appetite, weight loss, heat intolerance, fever, excessive sweating, headaches, anxiety, irritability, muscle weakness, rapid heartbeat, and digestive issues like diarrhea and cramps. Some people may also experience hair loss or skin flushing.
Pregnancy & Lactation
Synroid is considered safe to use during pregnancy, but the dose may need to be adjusted. Synroid is also safe during breastfeeding in normal doses, but caution is advised. Proper thyroid function is important for milk production.
Precautions & Warnings
People with pituitary problems may also have adrenal insufficiency, which should be treated before starting Levothyroxine. The starting dose should be carefully considered in patients with heart conditions or severe hypothyroidism, as too high of a dose can lead to heart problems. Any major changes in body weight require a dose adjustment. Monitoring TSH levels helps ensure the correct dosage.
Overdose Effects
Overdose symptoms are similar to hyperthyroidism, including agitation, irritability, rapid heartbeat, fever, excessive sweating, and diarrhea. In severe cases, Synroid can cause shock or even death. If an overdose is suspected, the dose should be reduced or stopped temporarily. Treatment is symptomatic.
Therapeutic Class
Synroid belongs to the class of thyroid drugs and hormones.
Storage Conditions
Store below 30°C in a dry place, away from light. Keep out of reach of children.
Similar Brands of Levothyroxine Sodium (Tablet – 50mcg)
| Brand Name | Form | Strength | Company | MRP (৳) |
|---|---|---|---|---|
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| Thyronor 50 | Tablet | 50mcg | Nuvista Pharma Ltd | 2.28 |
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