Synthroid (Levothyroxine)

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Synthroid Brand
Dosage Quantity & Price
Levothyroxine (Generic alternate to Synthroid) Generic

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Table of contents:

Synthroid is a popular prescription medication used to treat hypothyroidism. It contains an active ingredient called levothyroxine sodium. Levothyroxine is a synthetic form of the thyroid hormone and helps to replace the hormones that are naturally produced by the thyroid gland.

Synthroid has become a preferred form of treatment for people suffering from an underactive thyroid. It is not only effective but also easy to use and maintain daily. Levothyroxine is also used to treat other types of thyroid disorders such as thyroid cancer.

Uses and Dosage

Take Synthroid tablet exactly as prescribed by your healthcare provider. Take the tablet by mouth as directed by your doctor, usually once daily on an empty stomach, 30 minutes to 1 hour before breakfast. Drink Synthroid tablet with a full glass of water unless your doctor directs you otherwise. Swallow the whole tablet and do not split, crush, or chew. People who cannot swallow the capsule whole (such as infants or small children) should use the tablet form of the medication.

The dosage of Synthroid may vary depending on factors such as age, weight, medical condition, and response to treatment. However, the usual initial dose for adults with hypothyroidism is 1.6 to 1.7 mcg/kg body weight per day, which may be adjusted based on thyroid hormone blood levels and individual response. The maximum daily dosage generally should not exceed 200 mcg per day for most adults.

Side Effect

Common Side Effects of Synthroid (Levothyroxine):

  • Changes in your menstrual periods
  • Diarrhea
  • Feeling hot
  • Feeling nervous or irritable
  • Hair loss
  • Headache
  • Hot flashes
  • Increased appetite
  • Irritability
  • Nausea
  • Nervousness
  • Partial hair loss
  • Shortness of breath
  • Skin rash
  • Tremors
  • Weight loss or weight gain

Serious Side Effects of Synthroid (Levothyroxine):

  • Bone pain
  • Chest pain
  • Diarrhea
  • Fatigue
  • Increased sweating
  • Irregular heartbeat
  • Mental/mood changes
  • Seizures
  • Sensitivity to heat
  • Shortness of breath
  • Tremors

Form and Strength

Synthroid (Levothyroxine) is available in the following forms and strength:

Synthroid: Tablet

  • 0.025 mg
  • 0.05 mg
  • 0.075 mg
  • 0.088 mg
  • 0.100 mg
  • 0.112 mg
  • 0.125 mg
  • 0.137 mg
  • 0.15 mg
  • 0.175 mg
  • 0.200 mg
  • 0.300 mg


  • Before taking Synthroid or any other levothyroxine medication, inform your doctor or pharmacist of any allergies you may have, as the medication may contain inactive ingredients that could cause allergic reactions or other issues.
  • Do not change brands without consulting your healthcare provider.
  • Inform your healthcare provider if you have a history of heart disease, high blood pressure, diabetes, or adrenal gland problems as these conditions may affect how your body responds to Synthroid.
  • Inform your healthcare provider if you are pregnant or breastfeeding, as the dosage of Synthroid may need to be adjusted during these times.
  • Synthroid may interact with other medications, supplements, or foods, so inform your healthcare provider of any other medications or supplements you are taking.
  • Do not stop taking Synthroid abruptly, as this may lead to adverse effects. Always consult your healthcare provider before making any changes to your medication regimen.
  • Taking levothyroxine (Synthroid) can weaken bones over time, especially in women after menopause. Your provider will be monitoring your thyroid levels to make sure you are taking the lowest effective dose; this can lower your risk.

Frequently Asked Questions (FAQ)

Can Synthroid cause weight gain?

Weight gain is not a known side effect of Synthroid. However, if your dose of Synthroid is too low, it may not effectively manage your hypothyroidism symptoms, which could result in weight gain.

Are there any medications or foods that interact with Synthroid?

Yes, calcium supplements, iron supplements, and certain foods, such as soybean flour, cottonseed meal, walnuts, and dietary fiber, can interact with Synthroid and reduce its effectiveness.

How long does it take for Synthroid to work?

It may take several weeks for Synthroid to reach its full therapeutic effect.

What must I do if I miss my Synthroid dose?

If you miss your dosage for the day, take it right away, except if it is almost time for your next scheduled dose.

How long should I use Synthroid?

This medication is meant for long-term use.


It's important to purchase Synthroid from verified Canadian pharmacy.

Additional information

Generic name:





0.025mg, 0.05mg, 0.075mg, 0.088mg, 0.15mg, 0.100mg, 0.112mg, 0.125mg, 0.137mg, 0.175mg, 0.200mg, 0.300mg

Quantities Available:

60, 90