Thyronorm 50: Uses, How It Works, Side Effects

What is Thyronorm 50 used for?

Thyronorm 50 is used when the thyroid gland does not make enough thyroid hormone.

• Underactive thyroid (hypothyroidism), to replace the missing hormone
• Hypothyroidism caused by thyroid surgery, radioiodine treatment or an autoimmune thyroid condition, as decided by your doctor

How does Thyronorm 50 work?

The thyroid gland makes hormones that control how fast the body uses energy. When it makes too little, a person can feel tired, cold and low, and gain weight. Levothyroxine is a copy of the main thyroid hormone, thyroxine, so taking it every day replaces what is missing and brings the level in the blood back into the normal range.

What happens in your body after you take it

1. You swallow the tablet

   Levothyroxine is taken by mouth once a day, on an empty stomach with water, usually 30 to 60 minutes before breakfast. Food, tea, coffee and some other medicines can reduce how much is absorbed.

2. It is absorbed in the small intestine

   Most of the dose is absorbed in the small intestine and passes into the blood. Calcium, iron, antacids and some foods can bind it in the gut, which is why they are taken several hours apart.

3. It travels bound to proteins

   In the blood, nearly all levothyroxine attaches to carrier proteins. A very small free part reaches the body's cells.

4. It is converted where it is needed

   Thyroxine (T4) is a store form of the hormone. Tissues such as the liver and kidneys convert it into the more active hormone, T3, as the body needs it.

5. Metabolism returns to normal

   Once the hormone level is back in the normal range, the body's energy use, heart rate and temperature control work normally again. Symptoms such as tiredness, feeling cold and constipation gradually ease over weeks.

6. Blood tests guide the dose

   The doctor checks the thyroid stimulating hormone (TSH) blood test about 6 to 8 weeks after starting or changing the dose, then at intervals. The dose is adjusted until the test is in the target range.

7. It is slowly cleared

   Levothyroxine stays in the body for days (its half-life is about a week), so it is taken once a day and one missed dose is not usually a problem. The liver and kidneys clear it over time.

How to take Thyronorm 50

Take Thyronorm 50 exactly as your doctor advises or as printed on the pack. The dose is individual and is adjusted using blood tests, so never change it on your own.

• It is taken once a day, at the same time every day, usually in the morning on an empty stomach, 30 to 60 minutes before breakfast, tea or coffee, or other medicines.
• Swallow the tablet whole with a glass of water.
• Keep calcium, iron, antacids and similar medicines several hours away from the tablet. Ask your pharmacist what gap to leave.
• If you miss a dose, take it when you remember unless it is nearly time for the next one. Do not take two doses together.
• Most people need to take it for life. Do not stop even when you feel well, because the symptoms can return.
• Have the thyroid blood tests your doctor asks for. A dose that is too high or too low can cause symptoms.
• Any use in children is decided by a doctor, who sets the dose.

Side effects of Thyronorm 50

When the dose is right, levothyroxine usually causes few side effects. Most side effects happen when the dose is too high, which is why regular blood tests matter.

Uncommon or mild

• Trouble sleeping
• Headache
• Feeling anxious or nervous
• Sweating or feeling too hot
• Hair loss
• Shaky hands (tremor) or a fast, pounding heartbeat
• Diarrhoea or weight loss without trying

Who should be careful

Levothyroxine replaces a hormone the body needs, so it is usually taken for life, and the dose is set by blood tests. Too much is as much of a problem as too little.

• Heart disease, high blood pressure or an irregular heartbeat: too much thyroid hormone can strain the heart, so the doctor usually starts with a low dose and raises it slowly
• Adrenal gland problems (such as Addison's disease): these must be treated first, because levothyroxine can make them worse
• Diabetes: levothyroxine can change blood sugar, so your diabetes medicine doses may need to be reviewed
• Weak bones (osteoporosis) or being past the menopause: too high a dose can reduce bone strength, so the lowest effective dose is used
• Overactive thyroid: levothyroxine is generally not suitable
• Pregnancy or planning pregnancy: the dose often needs to rise during pregnancy, so tell your doctor early and do not stop the medicine on your own
• Not for weight loss: levothyroxine must not be used to lose weight, because larger doses can cause serious, even life-threatening, harm
• Biotin (vitamin B7) supplements, including those for hair and nails: they can affect thyroid blood test results, so tell the doctor or the lab
• Past allergic reaction to levothyroxine or any ingredient in the tablet

Medicines and things that interact with Thyronorm 50

Several common medicines and supplements stop the body absorbing levothyroxine, and a few change how much is needed. Tell your doctor or pharmacist about everything you take.

• Calcium tablets, iron tablets, antacids and sucralfate: they stop levothyroxine being absorbed properly, so they are usually taken several hours apart. Ask your pharmacist what gap to leave
• Medicines that lower stomach acid, such as omeprazole and other proton pump inhibitors: they can reduce how much levothyroxine is absorbed, so your doctor may check your thyroid blood tests
• Cholesterol medicines called bile acid sequestrants (such as colestyramine): they bind levothyroxine in the gut
• Soya products, high-fibre foods, walnuts and grapefruit juice: they can reduce absorption if taken close to the tablet
• Phenobarbital, rifampicin and sertraline: they may increase the dose of levothyroxine needed
• Warfarin and similar blood thinners: levothyroxine can increase their effect, so clotting tests may be needed
• Digoxin, amiodarone, some antidepressants and diabetes medicines: their effect or the dose needed can change when thyroid treatment starts or changes
• Biotin supplements: they can give misleading results in thyroid blood tests

If someone takes too much

Storage

Store in a cool, dry place in the original strip, away from direct light and moisture, and out of the reach of children. Check the storage line on the pack. Do not use after the expiry date.

Regulatory status in India

Approved for sale in India. Levothyroxine is not on the CDSCO list of banned medicines (the section 26A list was searched for this batch and has no levothyroxine entry). Thyronorm 50 contains levothyroxine only.

Other brands with the same medicine

Other brands and generic tablets contain levothyroxine sodium and work the same way, but they come in different strengths (such as 25, 50, 75, 100 and 125 mcg). Check the strength on the pack. Do not switch brands or strengths without asking your doctor.

Other strengths and forms

Thyronorm is sold in several strengths, and the strength is printed on the pack. Levothyroxine is also sold by other companies under other brand names. Check the strength every time you buy.

Common questions