Precautions
It is meant to replace a hormone that is usually made by your thyroid gland. Generally, SYNTHROID® (levothyroxine sodium) tablets, for oral use is a prescription, man-made thyroid hormone that is used to treat a condition called hypothyroidism.
What is Synthroid used to treat?
The goal of thyroid hormone treatment is to closely replicate normal thyroid functioning. Pure, synthetic thyroxine (T4) works in the same way as a patient’s own thyroid hormone would. Thyroid hormone is necessary for the health of all the cells in the body.
What is thyroid hormone treatment?
After a thyroidectomy, the body can no longer make the thyroid hormone it needs, so patients must take thyroid hormone (levothyroxine) pills to replace the loss of the natural hormone. Taking thyroid hormone may also help prevent some thyroid cancers from returning. Normal thyroid function is regulated by the pituitary gland.
Why do I need to take thyroid hormone after a thyroidectomy?
You will need to take thyroid hormone (levothyroxine) pills to replace the natural hormone and help maintain normal metabolism and possibly lower your risk of the cancer coming back. Normal thyroid function is regulated by the pituitary gland.
Why do I need to take thyroid hormone pills for cancer?
What type of thyroid is treated with SYNTHROID?
SYNTHROID® (levothyroxine sodium) tablets, for oral use is a prescription, man-made thyroid hormone that is used to treat a condition called hypothyroidism. It is meant to replace a hormone that is usually made by your thyroid gland. Generally, thyroid replacement treatment is to be taken for life.
What hormone does SYNTHROID replace?
Synthroid (levothyroxine) is a man-made version of T4, and Cytomel (liothyronine) is a man-made version of T3. Both medications can replace thyroid hormones when your levels are low.
Is SYNTHROID used for hyperthyroidism or hypothyroidism?
(4) Levothyroxine (brand name Synthroid) is standard in hypothyroid treatment. It helps replace missing thyroxine (T4) hormones in the body.
Which is drug of choice for thyroid hormone replacement therapy in hypothyroidism?
Levothyroxine is the treatment of choice for hypothyroidism.
What is the best thyroid replacement hormone?
The most commonly prescribed thyroid hormone replacement is pure synthetic thyroxine (T4).
How do you balance thyroid hormones?
Strategies to Naturally Balance Hormones & Your Thyroid:Utilize Better Testing Options.Balance Your Blood Sugar.Consider Taking Specific Supplements.Avoid “Toxic” Foods.Increase Your Consumption of Healthy Fats.
Who needs Synthroid?
Levothyroxine is used to treat an underactive thyroid (hypothyroidism). It replaces or provides more thyroid hormone, which is normally produced by the thyroid gland. Low thyroid hormone levels can occur naturally or when the thyroid gland is injured by radiation/medications or removed by surgery.
Does Synthroid raise or lower TSH?
* For thyroid stimulating hormone (TSH) suppression, Synthroid is used to help decrease levels of TSH in your body. TSH is made when your body needs thyroid hormones. A lower TSH level means your body doesn't need thyroid hormones as much as a higher TSH level indicates.
Which is worse hypothyroidism or hyperthyroidism?
Both can lead to death in the most severe cases. However, hypothyroidism is 5 times more common than hyperthyroidism. In severe cases, hypothyroidism can lead to heart disease and myxedema coma, both of which can lead to death.
What is first line treatment for hypothyroidism?
American Thyroid Association Continues to Recommend Levothyroxine as First-Line Therapy for Hypothyroidism.
What is the best treatment for an underactive thyroid?
An underactive thyroid (hypothyroidism) is usually treated by taking daily hormone replacement tablets called levothyroxine. Levothyroxine replaces the thyroxine hormone, which your thyroid does not make enough of. You'll initially have regular blood tests until the correct dose of levothyroxine is reached.
What is the treatment of choice for hypothyroidism?
Standard treatment for hypothyroidism involves daily use of the synthetic thyroid hormone levothyroxine (Levo-T, Synthroid, others). This oral medication restores adequate hormone levels, reversing the signs and symptoms of hypothyroidism.
Does levothyroxine cause weight gain or loss?
In most cases, levothyroxine causes some weight loss. According to the American Thyroid Association, when this medication is started, you may lose...
Can I take Cytomel and Synthroid together?
Although the American Thyroid Association guidelines do not recommend taking Cytomel and Synthroid together, many people who are under the supervis...
What can I eat for breakfast after taking levothyroxine?
Most foods are considered fine to eat for breakfast as long as they are eaten 30 to 60 minutes after taking levothyroxine. Levothyroxine should be...
Why is it important to take synthroid the same way every day?
In order for Synthroid to be effective, it should always be taken the same way every day. This is important because the amount of medicine you need is very precise. And even the way you take Synthroid can affect how much medicine your body is getting.
What foods can make Synthroid less effective?
Foods containing soy and cottonseed meal can make Synthroid less effective. Walnuts, grapefruit juice, and dietary fiber can also make Synthroid less effective. If you eat any of these on a regular basis, check with your doctor. He or she may need to adjust your dose of Synthroid.
How long before taking synthroid before iron?
Some supplements and medications can also interfere with the way Synthroid works. To avoid this, you should take Synthroid 4 hours before or after taking: Iron supplements and multivitamins with iron.
How long does it take for thyroid hormone to work?
And it may take several weeks before you notice Synthroid is working, and for your thyroid levels to adjust to the correct range.
What is the active ingredient in Synthroid?
The active ingredient in Synthroid is levothyroxine sodium, a man-made hormone that works in the same way as thyroxine. play_circle_outline. View Transcript.
How many doses of synthroid are there?
Synthroid comes in 12 dosing options to help your doctor find the dose that's right for you. Your doctor will determine your starting dose based on your weight, age, cause of hypothyroidism, and other health conditions, as well as other medications you’re taking.
How to administer Synthroid to infants?
Administer Synthroid to infants and children who cannot swallow intact tablets by crushing the tablet , suspending the freshly crushed tablet in a small amount (5 to 10 mL or 1 to 2 teaspoons) of water and immediately administering the suspension by spoon or dropper. Do not store the suspension.
What are the proteins that are bound to thyroid hormones?
Circulating thyroid hormones are greater than 99% bound to plasma proteins, including thyroxine-binding globulin (TBG), thyroxine-binding prealbumin (TBPA), and albumin (TBA), whose capacities and affinities vary for each hormone. The higher affinity of both TBG and TBPA for T4 partially explains the higher serum levels, slower metabolic clearance, and longer half-life of T4 compared to T3. Protein-bound thyroid hormones exist in reverse equilibrium with small amounts of free hormone. Only unbound hormone is metabolically active. Many drugs and physiologic conditions affect the binding of thyroid hormones to serum proteins [see Drug Interactions (7)]. Thyroid hormones do not readily cross the placental barrier [see Use in Specific Populations (8.1)].
How much TSH is suppressed?
Generally, TSH is suppressed to below 0.1 IU per liter, and this usually requires a Synthroid dose of greater than 2 mcg per kg per day. However, in patients with high-risk tumors, the target level for TSH suppression may be lower.
How is T4 absorbed?
The majority of the Synthroid dose is absorbed from the jejunum and upper ileum. The relative bioavailability of Synthroid tablets, compared to an equal nominal dose of oral levothyroxine sodium solution, is approximately 93%. T4 absorption is increased by fasting, and decreased in malabsorption syndromes and by certain foods such as soybeans. Dietary fiber decreases bioavailability of T4. Absorption may also decrease with age. In addition, many drugs and foods affect T4 absorption [see Drug Interactions (7)].
What hormones are involved in DNA transcription?
Thyroid hormones exert their physiologic actions through control of DNA transcription and protein synthesis. Triiodothyronine (T3) and L-thyroxine (T4) diffuse into the cell nucleus and bind to thyroid receptor proteins attached to DNA. This hormone nuclear receptor complex activates gene transcription and synthesis of messenger RNA and cytoplasmic proteins.
Does levothyroxine cause bone loss?
Increased bone resorption and decreased bone mineral density may occur as a result of levothyroxine over-replacement, particularly in post-menopausal women. The increased bone resorption may be associated with increased serum levels and urinary excretion of calcium and phosphorous, elevations in bone alkaline phosphatase, and suppressed serum parathyroid hormone levels. Administer the minimum dose of Synthroid that achieves the desired clinical and biochemical response to mitigate this risk.
Does levothyroxine affect glycemic control?
Addition of levothyroxine therapy in patients with diabetes mellitus may worsen glycemic control and result in increased antidiabetic agent or insulin requirements. Carefully monitor glycemic control after starting, changing, or discontinuing Synthroid [see Drug Interactions (7.2)].
What is the best medication for hypothyroidism?
Replaces or supplements low or missing thyroxine. Levothyroxine is recommended by American guidelines as the preferred treatment for hypothyroidism. Synthroid is a brand of levothyroxine. Synthroid may also be used in the management of goiter and some thyroid cancers.
What is the synthroid?
Tips. Response/effectiveness. Interactions. 1. How it works. Synthroid is a brand (trade) name for levothyroxine. Levothyroxine is a man-made form of thyroxine (also called T4), a naturally occurring hormone produced by the thyroid gland.
How long does it take for a synthroid to stabilize?
Levels of Synthroid may take 6-8 weeks to stabilize following a dosage change. Contact your doctor if you experience chest pain, shortness of breath, leg cramps, vomiting, diarrhea, excessive sweating, heat intolerance, fever, or a skin rash while taking Synthroid.
How much of a dose of synthroid is absorbed from the gastrointestinal tract?
6. Response and effectiveness. Only 40-60% of a dose of Synthroid is absorbed from the gastrointestinal tract.
What medications interact with synthroid?
Common medications that may interact with Synthroid include: amiodarone or other medications that affect iodine, such as radioactive iodine . amphetamines, such as dexamphetamine or phentermine. anticoagulants, such as warfarin. anticonvulsants such as carbamazepine, phenobarbital, or phenytoin.
How much of a dose of synthroid is absorbed?
Only 40-60% of a dose of Synthroid is absorbed from the gastrointestinal tract. Absorption is increased by fasting and decreased by certain foods, in older age, and by some medications.
What medications can affect the absorption of levothyroxine?
medications that can affect the absorption of levothyroxine, such as antacids, calcium carbonate, cholestyramine, iron, orlistat sucralfate, sevelamer, or proton pump inhibitors. rifampin. Note that this list is not all-inclusive and includes only common medications that may interact with Synthroid.
How long should I take Synthroid?
Synthroid comes as tablets that are taken by mouth once per day, without food. It’s usually recommended to take Synthroid 30 minutes to 1 hour before your first meal of the day. In general, the drug should be taken at about the same time each day, on an empty stomach (30 minutes to 1 hour before or after eating).
What to do if you miss a dose of Synthroid?
If you miss a dose of Synthroid, take it as soon as you remember. But if it’s close to the time of your next dose, skip the missed dose and take your next scheduled dose as usual. If you aren’t sure whether to take the missed dose or skip it, talk with your doctor or pharmacist.
How much Synthroid should I take a day?
If you’re an older adult or you have heart disease, your doctor may prescribe a specific starting dosage of 12.5 mcg to 25 mcg of Synthroid per day. This adjusted dosage helps your doctor monitor you for side effects that may affect your heart. This dosage may be increased gradually, every 6 to 8 weeks as needed.
How often should I adjust my thyroid medication?
Your doctor may adjust your Synthroid dosage every 2 to 6 weeks* when you first start treatment, based on your thyroid hormone levels. Your dosage will typically be adjusted by amounts of 12.5 mcg to 25 mcg. These adjustments may help the drug work more effectively or lower your risk for side effects.
How much Synthroid should I take for hypothyroidism?
The typical starting dosage for this use in adults is 12.5 mcg to 25 mcg, once per day. Your doctor may adjust your dosage every 2 to 4 weeks as needed during treatment.
How much is a kilo of synthroid?
One kilogram is equal to about 2.2 pounds (lb).
What is the best medication for thyroid cancer?
Overview. If you have hypothyroidism or thyroid cancer, your doctor might suggest Synthroid ( levothyroxine) as a treatment option for you. Synthroid is a prescription medication that’s used to: treat primary, secondary, or tertiary hypothyroidism in adults and children.
What is thyroid hormone therapy?
THYROID HORMONE TREATMENT. Thy roid hormone is used in two situations: to replace the function of the thyroid gland, which is no longer functioning normally ( “replacement therapy “) and. to prevent further growth of thyroid tissue (“ suppression therapy “). Suppression therapy is used primarily in patients with thyroid cancer to prevent recurrence ...
How to make sure thyroid hormone is correct?
The physician will make sure the thyroid hormone dose is correct by performing a physical examination and checking TSH levels. There are several brand names of thyroid hormone available.
What is the treatment for thyroid cancer?
After surgery for thyroid cancer, thyroid hormone is needed both to replace the function of the removed thyroid gland and to keep any small or residual amounts of thyroid cancer cells from growing (see Thyroid Cancer brochure ). Thyroid hormone suppression therapy is also an important part of the treatment ...
Why is thyroid hormone suppression used?
In the past, thyroid hormone suppression therapy was used to prevent benign thyroid nodules and enlarged thyroid glands from growing . More recent evidence has shown that this practice is not effective in regions of the world that have adequate iodine intake (such as the USA).
What medications can cause thyroid problems?
Medications that can potentially cause people to need a different dose of thyroid hormone include birth control pills, estrogen, testosterone, some anti-seizure medications ( for example Dilantin and Tegretol ), and some medications for depression.
Why is thyroid hormone different from other medications?
Therefore, taking thyroid hormone is different from taking other medications, because its job is to replace a hormone that is missing. The only safety concerns about taking thyroid hormone are taking too much or too little.
Why do we need thyroid hormone replacement?
Hypothyroidism, is the most common reason for needing thyroid hormone replacement. The goal of thyroid hormone treatment is to closely replicate normal thyroid functioning. Pure, synthetic thyroxine (T4) works in the same way as a patient’s own thyroid hormone would. Thyroid hormone is necessary for the health of all the cells in the body.
Why do you need levothyroxine?
You will need to take thyroid hormone (levothyroxine) pills to replace the natural hormone and help maintain normal metabolism and possibly lower your risk of the cancer coming back. Normal thyroid function is regulated by the pituitary gland. The pituitary makes a hormone called TSH that causes the thyroid gland to make thyroid hormone for ...
What hormone is produced by the pituitary gland?
The pituitary makes a hormone called TSH that causes the thyroid gland to make thyroid hormone for the body. TSH also promotes growth of the thyroid gland and probably of thyroid cancer cells. The level of TSH, in turn, is regulated by how much thyroid hormone is in the blood.
Does thyroid hormone make the pituitary less?
If the level of thyroid hormone is high, not as much TSH is needed, so the pituitary makes less of it. Doctors have learned that by giving higher than normal doses of thyroid hormone, TSH levels can be kept very low.
Can thyroid hormone cause heart problems?
Taking higher than normal levels of thyroid hormone seems to have few short-term side effects, but some doctors have expressed concerns about taking them for long periods of time. High levels of thyroid hormone can lead to problems with a rapid or irregular heartbeat.
What is hormone replacement therapy?
By Mayo Clinic Staff. Hormone replacement therapy is medication that contains female hormones. You take the medication to replace the estrogen that your body stops making during menopause. Hormone therapy is most often used to treat common menopausal symptoms, including hot flashes and vaginal discomfort.
How often should hormones be reevaluated?
For best results, hormone therapy should be tailored to each person and reevaluated every so often to be sure the benefits still outweigh the risks.
How old do you have to be to start hormone therapy?
Age. Women who begin hormone therapy at age 60 or older or more than 10 years from the onset of menopause are at greater risk of the above conditions. But if hormone therapy is started before the age of 60 or within 10 years of menopause, the benefits appear to outweigh the risks. Type of hormone therapy.
What is systemic estrogen?
Systemic estrogen — which comes in pill, skin patch, ring, gel, cream or spray form — typically contains a higher dose of estrogen that is absorbed throughout the body. It can be used to treat any of the common symptoms of menopause. Low-dose vaginal products.
What are the risks of taking estrogen pills?
In the largest clinical trial to date, hormone replacement therapy that consisted of an estrogen-progestin pill (Prempro) increased the risk of certain serious conditions, including: Heart disease. Stroke. Blood clots. Breast cancer.
How to manage hot flashes during menopause?
You may be able to manage menopausal hot flashes with healthy-lifestyle approaches such as keeping cool, limiting caffeinated beverages and alcohol, and practicing paced relaxed breathing or other relaxation techniques. There are also several nonhormone prescription medications that may help relieve hot flashes.
How old do you have to be to take estrogen?
Use the lowest effective dose for the shortest amount of time needed to treat your symptoms. If you're younger than age 45, you need enough estrogen to provide protection against the long-term health effects of estrogen deficiency.
Indications and Usage For Synthroid
Levothyroxine is used to treat an underactive thyroid (hypothyroidism).
May Treat: Adjunct to surgery or radiotherapy for thyroid carcinoma · Hypothyroidism · Myxedema coma
Alternate Brand Names: Levothroid · Levoxyl · Unithroid
Drug Class: Thyroid Hormones - Synthetic T4 (Thyroxine)
Availability: Prescription sometimes needed
Pregnancy: Consult a doctor before using
May Treat: Adjunct to surgery or radiotherapy for thyroid carcinoma · Hypothyroidism · Myxedema coma
Alternate Brand Names: Levothroid · Levoxyl · Unithroid
Drug Class: Thyroid Hormones - Synthetic T4 (Thyroxine)
Availability: Prescription sometimes needed
Pregnancy: Consult a doctor before using
Lactation: Does not adversely affect lactation
Alcohol: Limit intake while taking this medication
Driving: May cause drowsiness or dizziness. Use caution
Manufacturer: ABBVIE US LLC
- Not recommended to cause weight loss.
- Take daily, at least 30 minutes before breakfast
- Do not change brands without checking with Dr.
- Not recommended to cause weight loss.
- Take daily, at least 30 minutes before breakfast
- Do not change brands without checking with Dr.
- Tell MD now of chest pain or irregular heart rate.
- Call doctor if you missed 2 or more doses
- Review all drugs you are taking with your doctor
- Lab tests may be ordered to monitor therapy
- Swallow capsules whole.
- For capsule products : Do not chew or crush.
- For solution, oral products : If available, read the patient package insert.
- For tablet products : Do not miss any doses.
Synthroid Dosage and Administration
Contraindications
Warnings and Precautions
Adverse Reactions
- 2.1 General Administration Information
Administer Synthroid as a single daily dose, on an empty stomach, one-half to one hour before breakfast. Administer Synthroid at least 4 hours before or after drugs known to interfere with Synthroid absorption [see Drug Interactions (7.1)]. Evaluate the need for dose adjustments whe… - 2.2 General Principles of Dosing
The dose of Synthroid for hypothyroidism or pituitary TSH suppression depends on a variety of factors including: the patient's age, body weight, cardiovascular status, concomitant medical conditions (including pregnancy), concomitant medications, co-administered food and the speci…
Drug Interactions
- Synthroid is contraindicated in patients with uncorrected adrenal insufficiency [see Warnings and Precautions (5.3)].
Use in Specific Populations
- 5.1 Cardiac Adverse Reactions in the Elderly and in Patients with Underlying Cardiovascular Dise…
Over-treatment with levothyroxine may cause an increase in heart rate, cardiac wall thickness, and cardiac contractility and may precipitate angina or arrhythmias, particularly in patients with cardiovascular disease and in elderly patients. Initiate Synthroid therapy in this population at low… - 5.2 Myxedema Coma
Myxedema coma is a life-threatening emergency characterized by poor circulation and hypometabolism, and may result in unpredictable absorption of levothyroxine sodium from the gastrointestinal tract. Use of oral thyroid hormone drug products is not recommended to treat m…
Overdosage
- Adverse reactions associated with Synthroid therapy are primarily those of hyperthyroidism due to therapeutic overdosage [see Warnings and Precautions (5), Overdosage (10)]. They include the following: 1. General:fatigue, increased appetite, weight loss, heat intolerance, fever, excessive sweating 2. Central nervous system:headache, hyperactivity, nervousness, anxiety, irritability, em…
Synthroid Description
- 7.1 Drugs Known to Affect Thyroid Hormone Pharmacokinetics
Many drugs can exert effects on thyroid hormone pharmacokinetics and metabolism (e.g., absorption, synthesis, secretion, catabolism, protein binding, and target tissue response) and may alter the therapeutic response to Synthroid (see Tables 2-5below). - 7.2 Antidiabetic Therapy
Addition of Synthroid therapy in patients with diabetes mellitus may worsen glycemic control and result in increased antidiabetic agent or insulin requirements. Carefully monitor glycemic control, especially when thyroid therapy is started, changed, or discontinued [see Warnings and Precauti…
Synthroid - Clinical Pharmacology
- 8.1 Pregnancy
Risk Summary Experience with levothyroxine use in pregnant women, including data from post-marketing studies, have not reported increased rates of major birth defects or miscarriages [see Data]. There are risks to the mother and fetus associated with untreated hypothyroidism in preg… - 8.2 Lactation
Risk Summary Limited published studies report that levothyroxine is present in human milk. However, there is insufficient information to determine the effects of levothyroxine on the breastfed infant and no available information on the effects of levothyroxine on milk production…