How does levothyroxine work?
Levothyroxine works by restoring normal thyroid hormone levels in the body. This helps regulate metabolism, energy production, and growth, reducing the symptoms of an underactive thyroid.
What is levothyroxine used to treat?
Levothyroxine is mainly used to treat:
- Hypothyroidism (underactive thyroid)
- Goitre (an enlarged thyroid gland)
- Thyroid cancer (to suppress thyroid-stimulating hormone after treatment)
Who can take levothyroxine?
Most adults and children with hypothyroidism can take levothyroxine. It is usually a lifelong treatment.
Who might not be able to take levothyroxine?
Levothyroxine may not be suitable if you:
- Have an untreated adrenal gland problem
- Have a severe heart condition (such as angina or heart failure)
- Have had an allergic reaction to levothyroxine or any of its ingredients
Can I take levothyroxine if I’m pregnant or breastfeeding?
Yes, levothyroxine is safe and important to take during pregnancy and while breastfeeding. If you are pregnant, your doctor may adjust your dose to ensure your thyroid hormone levels stay balanced.
What if I miss a dose?
If you forget a dose, take it as soon as you remember. If it’s close to your next dose, skip the missed one—don’t take two doses at once.
How effective is levothyroxine?
Levothyroxine is highly effective when taken correctly. Most people feel an improvement within a few weeks, but it may take time to fully stabilise hormone levels.
What should I do if I take too much?
Taking too much levothyroxine can cause symptoms of hyperthyroidism, including:
- A racing heart
- Sweating
- Weight loss
- Feeling anxious or restless
If you think you’ve taken too much, speak to a doctor straight away.
What dose of levothyroxine is usually taken?
Doses vary depending on the individual’s needs, but typical doses include:
- Adults: 50–200 micrograms once daily
- Children: Lower doses based on weight and age
- Elderly or those with heart conditions: Usually start on a lower dose
Your doctor will monitor your thyroid levels and adjust the dose if needed.
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What are the side effects of levothyroxine?
Most people tolerate levothyroxine well, but some may experience:
- Headaches
- Sweating
- Palpitations (fast heartbeat)
- Weight loss
- Feeling restless or anxious
If you experience chest pain, extreme fatigue, or severe weight loss, seek medical advice.
How should I take levothyroxine?
Levothyroxine should be taken as a tablet or liquid, usually once daily. It’s best to take it on an empty stomach with water, at least 30 minutes before eating.
When should levothyroxine be taken?
Levothyroxine is usually taken in the morning, as food can affect its absorption. Try to take it at the same time every day.
What are the brand names for levothyroxine?
Levothyroxine is available under different brand names, including:
- Eltroxin
- Levothyroid
Final thoughts
Levothyroxine is an essential treatment for hypothyroidism and should be taken exactly as prescribed. Regular blood tests help ensure you’re on the right dose. If you have concerns, speak to your doctor or pharmacist.
