Synthroid
Synthroid is a synthetic form of the thyroid hormone thyroxine (T4). It is used to replace thyroid hormone that is normally produced by your thyroid gland. Without this hormone, your body cannot function properly, leading to symptoms like poor growth, slow speech, lack of energy, and weight gain.
Dosage by Body Weight
Take Synthroid exactly as prescribed by your doctor. It should be taken once daily on an empty stomach, 30 to 60 minutes before breakfast, with a full glass of water. Dosage is highly individualized and adjusted based on regular blood tests (TSH and free T4). Do not switch brands without consulting your doctor.
- Body Weight
- Below 5 kg
- Dose
- 10 - 15 mcg/kg per day
- Frequency
- Once daily
- Tracking Notes
- Commonly for neonates and infants. Administer by crushing the tablet and suspending it in a small amount of water or breast milk. Avoid mixing with soy-based formula.
- Body Weight
- 5-7 kg
- Dose
- 6 - 10 mcg/kg per day (approx. 25 - 50 mcg)
- Frequency
- Once daily
- Tracking Notes
- Monitor clinical response and thyroid hormone levels closely. Ensure consistent administration timing.
- Body Weight
- 8-10 kg
- Dose
- 5 - 8 mcg/kg per day (approx. 50 - 75 mcg)
- Frequency
- Once daily
- Tracking Notes
- Absorption can be decreased by calcium, iron, or soy. Avoid administering these within 4 hours of Synthroid.
- Body Weight
- 11-15 kg
- Dose
- 4 - 6 mcg/kg per day (approx. 75 - 100 mcg)
- Frequency
- Once daily
- Tracking Notes
- Dosage adjustments are typically done in increments of 12.5 to 25 mcg based on laboratory results.
- Body Weight
- 16-20 kg
- Dose
- 3 - 5 mcg/kg per day (approx. 100 - 125 mcg)
- Frequency
- Once daily
- Tracking Notes
- Ensure child swallows the tablet whole or crushed in water; do not allow chewing. Administer on an empty stomach.
| Body Weight | Dose | Frequency | Tracking Notes |
|---|---|---|---|
| Below 5 kg | 10 - 15 mcg/kg per day | Once daily | Commonly for neonates and infants. Administer by crushing the tablet and suspending it in a small amount of water or breast milk. Avoid mixing with soy-based formula. |
| 5-7 kg | 6 - 10 mcg/kg per day (approx. 25 - 50 mcg) | Once daily | Monitor clinical response and thyroid hormone levels closely. Ensure consistent administration timing. |
| 8-10 kg | 5 - 8 mcg/kg per day (approx. 50 - 75 mcg) | Once daily | Absorption can be decreased by calcium, iron, or soy. Avoid administering these within 4 hours of Synthroid. |
| 11-15 kg | 4 - 6 mcg/kg per day (approx. 75 - 100 mcg) | Once daily | Dosage adjustments are typically done in increments of 12.5 to 25 mcg based on laboratory results. |
| 16-20 kg | 3 - 5 mcg/kg per day (approx. 100 - 125 mcg) | Once daily | Ensure child swallows the tablet whole or crushed in water; do not allow chewing. Administer on an empty stomach. |
Formulation
Purpose
Used to treat hypothyroidism (underactive thyroid) and to suppress thyroid-stimulating hormone (TSH) in patients with goiters or thyroid cancer.
Generic Name
Levothyroxine sodiumScheduled Drug
No. This medicine is generally not treated as a scheduled/prescription-only drug in common consumer references, but local rules may vary.