About levothyroxine

Levothyroxine is the same as the hormone thyroxine which is produced in the body by the thyroid gland. Levothyroxine is given when the thyroid gland is not producing enough thyroxine.

Before taking levothyroxine

Before taking levothyroxine make sure your doctor or pharmacist knows:

• If you are pregnant, trying for a baby or breast-feeding.
• If you have heart problems or high blood pressure.
• If you know you suffer from adrenal insufficiency (this is where your adrenal gland is unable to produce enough of the hormone cortisol).
• If you have diabetes mellitus (sugar diabetes) or diabetes insipidus.
• If you have been told your thyroid gland produces too much thyroid hormone.
• If you are taking other medicines, including those available to buy without a prescription, herbal and complementary medicines.
• If you have ever had an allergic reaction to this or any other medicine.

How to take levothyroxine

• Before starting this treatment, read the manufacturer's printed information leaflet.
• Take levothyroxine exactly as your doctor has told you.
• Levothyroxine is usually taken once daily, before breakfast.
• If you forget to take a dose, take it as soon as you remember if this is within 2 or 3 hours of your usual time. If you do not remember until after this time, skip the forgotten dose. Do not take two doses together to make up for a missed dose.

Getting the most from your treatment

• Keep your regular appointments with your doctor so your progress can be monitored. You will need regular blood tests to check your thyroid levels in the early stages of your treatment.
• If you buy any medicines, check with a pharmacist that they are safe to take with levothyroxine. Levothyroxine should not be taken at the same time as indigestion remedies or preparations containing calcium or iron (which are contained in some vitamin products) as these can reduce the amount of levothyroxine absorbed by your body. Leave at least 2 hours between your dose of levothyroxine and any such preparations.
• If you are having any treatment like an operation or dental treatment, tell the person carrying out the treatment that you are taking levothyroxine.

Can levothyroxine cause problems?

Along with their useful effects, most medicines can cause unwanted side-effects although not everyone experiences them. These usually improve as your body adjusts to the new medicine, but speak with your doctor or pharmacist if any of the following side-effects become troublesome as your dose of levothyroxine may need to be adjusted.

If you experience any other symptoms which you think may be due to this medicine, speak with your doctor or pharmacist.

How to store levothyroxine

• Keep all medicines out of the reach and sight of children.
• Store in a cool, dry place, away from direct heat and light.

Important information about all medicines