Levothyroxine
About Levothyroxine
Levothyroxine is a prescription thyroid hormone replacement used to treat hypothyroidism, a condition where the thyroid gland does not produce enough thyroid hormone. It is also used to help suppress thyroid-stimulating hormone levels in patients with certain types of thyroid cancer. By providing the body with the hormone it lacks, this medicine helps restore normal metabolic functions.
To achieve the best results, you must take Levothyroxine once daily, consistently at the same time every day, on an empty stomach. It is best taken in the morning with a full glass of water, at least 30 to 60 minutes before eating breakfast or drinking caffeinated beverages. Maintaining a consistent diet and avoiding sudden changes in your fibre, soy, or calcium intake can also help ensure the medication is absorbed properly.
While starting this medication, some people may experience mild side effects like temporary hair loss, mild headaches, or feeling overly warm as their body adjusts. However, you should contact your doctor immediately if you experience severe symptoms, such as an irregular heartbeat, chest pain, or extreme shortness of breath.
Before taking this medicine, you must tell your doctor if you have a history of heart disease, diabetes, or problems with your adrenal or pituitary glands. Do not take this if you have an untreated overactive thyroid gland or an uncorrected adrenal gland problem that has not been treated. Your doctor will help determine if this therapy is safe for your specific health profile.
This medication can interact with other drugs, including antacids, iron supplements, and certain cholesterol medicines, which can prevent your body from absorbing it properly. You should also consult your doctor if you are pregnant, planning to become pregnant, breastfeeding, or are an older adult, as your dosage needs may change or require closer monitoring.
Uses of Levothyroxine
Medicinal Benefits
Levothyroxine helps restore normal thyroid hormone levels, relieving the symptoms of an underactive thyroid and supporting your body's normal metabolic functions. With regular use, it improves energy levels, enhances mental clarity, and promotes overall well-being.
- Boosts Energy and Reduces Fatigue: By restoring healthy thyroid hormone levels, this medicine helps reduce the persistent tiredness and physical weakness associated with hypothyroidism, allowing you to feel more energetic throughout the day.
- Supports a Healthy Metabolism: This medicine helps normalise your body's metabolism, supporting stable weight management, improving tolerance to cold temperatures, and relieving symptoms such as dry skin and thinning hair.
- Improves Mental Clarity: By correcting low thyroid hormone levels, this medicine helps reduce brain fog, forgetfulness, and difficulty concentrating, supporting better cognitive function and daily productivity.
Directions for Use
- It should be taken on an empty stomach, 30 minutes to 1 hour before breakfast, as advised by the doctor.
- Follow your doctor's instructions on the dosage and timing of this medication to ensure safety.
- Swallow Levothyroxine as a whole with a glass of water.
- Do not chew, crush or break it.
Storage
Side Effects of Levothyroxine
Common Side Effects (Usually mild):
- Mild headaches
- Temporary hair loss (especially in children starting treatment)
- Feeling hot or sweating more than usual
- Mild changes in appetite or weight
- Feeling slightly nervous or restless
Serious Side Effects (Consult a doctor right away):
- Chest pain, pressure, or tightness
- A rapid, pounding, or irregular heartbeat (palpitations)
- Severe shortness of breath or difficulty breathing
- Tremors, extreme nervousness, or severe sleep problems
- Signs of a severe allergic reaction, such as a skin rash, itching, hives, or swelling of the face, lips, tongue, or throat
Medicines Containing this Salt
View AllDrug Warnings
- Do not switch brands: Different brands of this medication can behave slightly differently in the body. Try to stick to the exact same brand of Levothyroxine, and consult your doctor before accepting a substitution.
- Do not use for weight loss: This medication is not a weight loss aid. Taking excessive amounts of thyroid hormone to lose weight can cause dangerous, life-threatening side effects, especially on your heart.
- Get regular blood tests: You will need periodic blood tests to monitor your thyroid hormone levels. This helps your doctor adjust your dose safely and ensures you are receiving the correct amount.
- Inform other healthcare providers: Let all your doctors, dentists, and pharmacists know that you are taking Levothyroxine, especially before undergoing surgery or starting any new prescriptions.
Drug Interactions
- Antacids, calcium carbonates, and iron supplements: These can bind to the medication in your stomach and significantly decrease its absorption. Space these at least 4 hours apart from your dose.
- Blood thinners (like warfarin): This medicine may increase the effects of blood thinners, which can increase your risk of bleeding. Your doctor may need to adjust your blood thinner dose.
- Diabetes medications: Starting this medicine may change your blood sugar control, potentially requiring an adjustment in your insulin or oral diabetes medication doses.
Drug-Drug Interactions Checker List:
Safety Advice
Alcohol
consult your doctorThe interaction of Levothyroxine with alcohol is unknown. Please consult a doctor before consuming alcohol while using Levothyroxine.
Pregnancy
consult your doctorPlease consult a doctor if you are pregnant. Levothyroxine is given to pregnant women if the doctor thinks the benefits outweigh the risks.
Breast Feeding
consult your doctorPlease consult a doctor if you are breastfeeding. Your doctor may adjust the dose appropriately if you are breastfeeding.
Driving
safe if prescribedLevothyroxine usually does not affect your ability to drive or operate machinery.
Liver
consult your doctorIf you have any concerns regarding the use of Levothyroxine in patients with Liver problems, please consult a doctor.
Kidney
consult your doctorIf you have any concerns regarding using Levothyroxine in patients with kidney problems, please consult a doctor.
Children
cautionYour doctor may adjust the dose according to your child's age, weight and other pre-existing conditions. Levothyroxine should be used for children as advised by the doctor.
Habit Forming
Diet & Lifestyle Advise
- Avoid calcium and iron around your dose: Do not take calcium supplements, iron supplements, or antacids containing aluminium or magnesium within 4 hours of taking your thyroid medication, as they can significantly reduce its absorption.
- Be consistent with soy and fibre: High-fibre foods, soy flour, walnuts, and grapefruit juice can lower the absorption of this medication. You do not need to avoid these foods entirely, but you should keep your intake of them consistent and talk to your doctor if you make major dietary changes.
- Limit caffeine in the morning: Avoid drinking coffee or tea for at least 30 to 60 minutes after taking your tablet, as caffeine can interfere with how the medicine is absorbed.
Special Advise
Regular blood tests are recommended while taking Levothyroxine to monitor the effect of Levothyroxine.
Patients Concern
Disease/Condition Glossary
Hypothyroidism: It is also known as underactive thyroid, a chronic condition when the thyroid gland does not make enough thyroid hormones to meet your body’s needs. When there is a low level of thyroid hormones, our body’s functions and metabolism slow down. Symptoms of hypothyroidism include tiredness, increased sensitivity to cold, constipation, dry skin, unexplained weight gain, puffy face, hoarseness of voice, and muscle weakness. There may be a loss of Calcium and Vitamin D in some cases of hypothyroidism.
FAQs
Levothyroxine is used to treat hypothyroidism (underactive thyroid gland).
Levothyroxine contains Levothyroxine that works by replacing thyroxine (a thyroid hormone) naturally produced by the thyroid gland. Thus, it restores the levels of thyroid hormones.
Levothyroxine should be used with caution in diabetic patients as it may increase blood sugar levels. Therefore, inform your doctor if you have diabetes so that the dose may be adjusted appropriately.
Hair loss may occur during the first few months of treatment in children. This effect is usually temporary, and hair regrows. If this effect persists or worsens, tell your doctor for further treatment.
You are not recommended to take Levothyroxine with phenytoin (anticonvulsant) as it may reduce the effectiveness of Levothyroxine. However, please consult a doctor before taking Levothyroxine with other medicines.
Levothyroxine may cause thyroid crisis (severe reaction to high thyroid hormone levels) in some patients. However, if you experience a fast heart rate, confusion, fits, low blood pressure, jaundice, very high fever, or irregular heartbeat, please consult a doctor immediately.
No, Levothyroxine should not be used for the treatment of obesity or for weight loss. It is used to treat hypothyroidism. However, taking Levothyroxine can lead to weight loss, mainly due to losing water weight. As your thyroid hormone levels become balanced, you may expect to lose up to 10% of your body weight. This weight loss is often most noticeable when you first start the medication.
Take Levothyroxine once daily in the morning, at least 30 minutes before breakfast, or caffeinated drinks like tea or coffee. This helps your body absorb the medication properly, ensuring it works effectively. Food and caffeine can interfere with absorption, so it's best to take it on an empty stomach.
Do not stop taking Levothyroxine without talking to your doctor. Stopping it suddenly can cause recurring symptoms like fatigue, dry skin, thinning hair, and weight gain. As hypothyroidism is a chronic condition, you may need to take Levothyroxine for life. Talk to the doctor if you have any difficulties while taking Levothyroxine.
Avoid exceeding the recommended dose as it could lead to an overdose. Symptoms of overdose may include fever, angina (chest pain), irregular heartbeat, headache, muscle cramps, flushing, restlessness, diarrhoea, shaking (tremors), sweating, insomnia (difficulty sleeping), and hyperpyrexia (very high temperature). If you take too much levothyroxine or experience any of these symptoms contact your doctor immediately.
You are recommended to take Levothyroxine for as long as it has been prescribed by the doctor. As hypothyroidism is a chronic condition, you may need to take Levothyroxine for life. Consult the doctor if you have any concerns regarding the duration of treatment.
Swallow it as a whole with a glass of water. Do not crush, chew, or break it.
If you are diabetic, you should be aware that Levothyroxine might raise blood sugar levels. Therefore, dose adjustment of anti-diabetic medicines may be needed. Keep your doctor informed if you are diabetic to ensure your diabetes and thyroid conditions are well-managed.
Thyroxine is a vital hormone that helps your body work properly. It regulates how your body uses energy, affects your heart rate, and helps your brain, muscles, and bones work correctly.
Levothyroxine does not affect contraception. However, combined pills which contain oestrogen may lower the amount of levothyroxine in the body. Therefore, talk to the doctor if you are taking a combined pill during treatment with Levothyroxine. Also, contraceptives may not be effective if you have vomiting or diarrhoea for over 24 hours while taking Levothyroxine.
The common side effects of Levothyroxine may include vomiting, headache, diarrhoea, restlessness, weight loss, irregular or fast heartbeat, restlessness, muscle weakness, or excitability. Most of these side effects of Levothyroxine do not require medical attention and gradually resolve over time. However, if the side effects persist or worsen, please consult your doctor.
No, you should not take calcium supplements at the same time. Calcium can bind to the medication in your stomach and prevent your body from absorbing it properly. You should space calcium supplements, antacids, or calcium-rich foods at least 4 hours apart from your dose. Talk to your doctor or pharmacist if you need help scheduling your supplements.
For most people with hypothyroidism, thyroid hormone replacement therapy is a lifelong treatment because the thyroid gland cannot recover its function. However, the exact duration of treatment depends on the underlying cause of your condition. Always talk to your doctor before making any changes to your therapy.
No, you should avoid drinking coffee, tea, or any other caffeinated beverages for at least 30 to 60 minutes after taking your tablet. Caffeine can significantly reduce how much of the medication your body absorbs, which can make your treatment less effective. Talk to your doctor or pharmacist if you find it difficult to stick to this routine.
Yes, it is generally safe and crucial to continue taking this medicine during pregnancy to support both your health and your baby's development. In fact, your dosage needs will likely increase during pregnancy, so you will need regular blood tests. Talk to your doctor as soon as you know you are pregnant to manage your dosage safely.
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