Synthroid

Hypothyroidism, Comatose, euthyroid Goitre + 3 more
Treatment
5 FDA approvals
11 Active Studies for Synthroid

What is Synthroid

LevothyroxineThe Generic name of this drug
Treatment SummaryLevothyroxine, also known as L-thyroxine or Synthroid, is a synthetic form of thyroxine which is a hormone naturally produced by the thyroid gland. It is used to treat hypothyroidism, a condition where the body does not make enough thyroid hormones. Common symptoms of hypothyroidism include fatigue, increased heart rate, depression, dry skin and hair, muscle cramps, constipation, weight gain, memory issues, and difficulty with cold temperatures. Levothyroxine helps to restore normal levels of hormones in the body and can be prescribed to both adults and children. It is usually more effective
Thyrolaris the brand name
image of different drug pills on a surface
Synthroid Overview & Background
Brand Name
Generic Name
First FDA Approval
How many FDA approvals?
Thyrolar
Levothyroxine
1969
1177

Approved as Treatment by the FDA

Levothyroxine, also known as Thyrolar, is approved by the FDA for 5 uses including Hypothyroidism and thyrotropin dependent Thyroid cancer .
Hypothyroidism
Helps manage Hypothyroidism
thyrotropin dependent Thyroid cancer
Hypothyroidism
Helps manage Hypothyroidism
Malignant Neoplasms
euthyroid Goitre
Helps manage euthyroid Goitre

Effectiveness

How Synthroid Affects PatientsLevothyroxine is a synthetic hormone that replaces the natural hormone T4 when there is a deficiency. It needs to be carefully adjusted to maintain the right levels in the body, otherwise it can cause problems with growth and development, heart health, reproductive function, thinking, emotions, digestive system, and blood sugar and cholesterol. In people with heart problems, levothyroxine should be started with a lower dose since too much can cause a faster heart rate, thicker heart walls, and other issues. Overusing levothyroxine can also lead to weaker bones, especially in post-menopausal women. For those with diabetes, starting or
How Synthroid works in the bodyLevothyroxine is a synthetic form of a hormone produced by the thyroid gland. This hormone increases the metabolic rate of cells in the body, helps with growth and development in fetuses and newborns, and helps adults maintain brain function and body temperature. When there is a deficiency of this hormone, people can experience slow speech, lack of energy, weight gain, hair loss, dry skin, and cold sensitivity. Levothyroxine works by binding to DNA and causing changes in gene expression. It also binds to plasma membrane receptors and can cause downstream effects like angiogenesis and tumor cell proliferation.

When to interrupt dosage

The measure of Synthroid is dependent upon the diagnosed disorder, such as Comatose, Edematous Fibrosclerotic Panniculopathy (Cellulite) and Adiposity. The amount of dosage can be found in the table below, contingent upon the technique of delivery.
Condition
Dosage
Administration
Hypothyroidism
, 0.025 mg, 0.05 mg, 0.075 mg, 0.088 mg, 0.1 mg, 0.112 mg, 0.125 mg, 0.15 mg, 0.175 mg, 0.2 mg, 0.3 mg, 0.137 mg, 0.038 mg, 0.019 mg, 0.057 mg, 0.038 mCi, 0.5 mg, 0.2 mg/mL, 0.5 mg/mL, 0.1 mg/mL, 0.0095 mg, 0.013 mg, 0.076 mg, 0.0125 mg, 0.114 mg, 0.15 mg/mL, 0.137 mg/mL, 0.175 mg/mL, 0.112 mg/mL, 0.125 mg/mL, 0.088 mg/mL, 0.075 mg/mL, 0.05 mg/mL, 0.025 mg/mL, 0.013 mg/mL, 0.04 mg/mL, 0.02 mg/mL, 0.0375 mg/mL, 0.0625 mg/mL, 0.044 mg/mL
, Oral, Tablet, Tablet - Oral, Topical, Tablet - Topical, Intravenous, Liquid, Liquid - Intravenous, Intramuscular; Intravenous, Powder, for solution, Powder, for solution - Intramuscular; Intravenous, Injection, powder, lyophilized, for solution, Injection, powder, lyophilized, for solution - Intravenous, Capsule, Capsule - Oral, Solution, Solution - Oral, Injection - Intravenous, Injection, Injection, solution, Injection, solution - Intravenous, Solution - Intramuscular; Intravenous
Cellulite
, 0.025 mg, 0.05 mg, 0.075 mg, 0.088 mg, 0.1 mg, 0.112 mg, 0.125 mg, 0.15 mg, 0.175 mg, 0.2 mg, 0.3 mg, 0.137 mg, 0.038 mg, 0.019 mg, 0.057 mg, 0.038 mCi, 0.5 mg, 0.2 mg/mL, 0.5 mg/mL, 0.1 mg/mL, 0.0095 mg, 0.013 mg, 0.076 mg, 0.0125 mg, 0.114 mg, 0.15 mg/mL, 0.137 mg/mL, 0.175 mg/mL, 0.112 mg/mL, 0.125 mg/mL, 0.088 mg/mL, 0.075 mg/mL, 0.05 mg/mL, 0.025 mg/mL, 0.013 mg/mL, 0.04 mg/mL, 0.02 mg/mL, 0.0375 mg/mL, 0.0625 mg/mL, 0.044 mg/mL
, Oral, Tablet, Tablet - Oral, Topical, Tablet - Topical, Intravenous, Liquid, Liquid - Intravenous, Intramuscular; Intravenous, Powder, for solution, Powder, for solution - Intramuscular; Intravenous, Injection, powder, lyophilized, for solution, Injection, powder, lyophilized, for solution - Intravenous, Capsule, Capsule - Oral, Solution, Solution - Oral, Injection - Intravenous, Injection, Injection, solution, Injection, solution - Intravenous, Solution - Intramuscular; Intravenous
Adiposity
, 0.025 mg, 0.05 mg, 0.075 mg, 0.088 mg, 0.1 mg, 0.112 mg, 0.125 mg, 0.15 mg, 0.175 mg, 0.2 mg, 0.3 mg, 0.137 mg, 0.038 mg, 0.019 mg, 0.057 mg, 0.038 mCi, 0.5 mg, 0.2 mg/mL, 0.5 mg/mL, 0.1 mg/mL, 0.0095 mg, 0.013 mg, 0.076 mg, 0.0125 mg, 0.114 mg, 0.15 mg/mL, 0.137 mg/mL, 0.175 mg/mL, 0.112 mg/mL, 0.125 mg/mL, 0.088 mg/mL, 0.075 mg/mL, 0.05 mg/mL, 0.025 mg/mL, 0.013 mg/mL, 0.04 mg/mL, 0.02 mg/mL, 0.0375 mg/mL, 0.0625 mg/mL, 0.044 mg/mL
, Oral, Tablet, Tablet - Oral, Topical, Tablet - Topical, Intravenous, Liquid, Liquid - Intravenous, Intramuscular; Intravenous, Powder, for solution, Powder, for solution - Intramuscular; Intravenous, Injection, powder, lyophilized, for solution, Injection, powder, lyophilized, for solution - Intravenous, Capsule, Capsule - Oral, Solution, Solution - Oral, Injection - Intravenous, Injection, Injection, solution, Injection, solution - Intravenous, Solution - Intramuscular; Intravenous
euthyroid Goitre
, 0.025 mg, 0.05 mg, 0.075 mg, 0.088 mg, 0.1 mg, 0.112 mg, 0.125 mg, 0.15 mg, 0.175 mg, 0.2 mg, 0.3 mg, 0.137 mg, 0.038 mg, 0.019 mg, 0.057 mg, 0.038 mCi, 0.5 mg, 0.2 mg/mL, 0.5 mg/mL, 0.1 mg/mL, 0.0095 mg, 0.013 mg, 0.076 mg, 0.0125 mg, 0.114 mg, 0.15 mg/mL, 0.137 mg/mL, 0.175 mg/mL, 0.112 mg/mL, 0.125 mg/mL, 0.088 mg/mL, 0.075 mg/mL, 0.05 mg/mL, 0.025 mg/mL, 0.013 mg/mL, 0.04 mg/mL, 0.02 mg/mL, 0.0375 mg/mL, 0.0625 mg/mL, 0.044 mg/mL
, Oral, Tablet, Tablet - Oral, Topical, Tablet - Topical, Intravenous, Liquid, Liquid - Intravenous, Intramuscular; Intravenous, Powder, for solution, Powder, for solution - Intramuscular; Intravenous, Injection, powder, lyophilized, for solution, Injection, powder, lyophilized, for solution - Intravenous, Capsule, Capsule - Oral, Solution, Solution - Oral, Injection - Intravenous, Injection, Injection, solution, Injection, solution - Intravenous, Solution - Intramuscular; Intravenous
Malignant Neoplasms
, 0.025 mg, 0.05 mg, 0.075 mg, 0.088 mg, 0.1 mg, 0.112 mg, 0.125 mg, 0.15 mg, 0.175 mg, 0.2 mg, 0.3 mg, 0.137 mg, 0.038 mg, 0.019 mg, 0.057 mg, 0.038 mCi, 0.5 mg, 0.2 mg/mL, 0.5 mg/mL, 0.1 mg/mL, 0.0095 mg, 0.013 mg, 0.076 mg, 0.0125 mg, 0.114 mg, 0.15 mg/mL, 0.137 mg/mL, 0.175 mg/mL, 0.112 mg/mL, 0.125 mg/mL, 0.088 mg/mL, 0.075 mg/mL, 0.05 mg/mL, 0.025 mg/mL, 0.013 mg/mL, 0.04 mg/mL, 0.02 mg/mL, 0.0375 mg/mL, 0.0625 mg/mL, 0.044 mg/mL
, Oral, Tablet, Tablet - Oral, Topical, Tablet - Topical, Intravenous, Liquid, Liquid - Intravenous, Intramuscular; Intravenous, Powder, for solution, Powder, for solution - Intramuscular; Intravenous, Injection, powder, lyophilized, for solution, Injection, powder, lyophilized, for solution - Intravenous, Capsule, Capsule - Oral, Solution, Solution - Oral, Injection - Intravenous, Injection, Injection, solution, Injection, solution - Intravenous, Solution - Intramuscular; Intravenous
Comatose
, 0.025 mg, 0.05 mg, 0.075 mg, 0.088 mg, 0.1 mg, 0.112 mg, 0.125 mg, 0.15 mg, 0.175 mg, 0.2 mg, 0.3 mg, 0.137 mg, 0.038 mg, 0.019 mg, 0.057 mg, 0.038 mCi, 0.5 mg, 0.2 mg/mL, 0.5 mg/mL, 0.1 mg/mL, 0.0095 mg, 0.013 mg, 0.076 mg, 0.0125 mg, 0.114 mg, 0.15 mg/mL, 0.137 mg/mL, 0.175 mg/mL, 0.112 mg/mL, 0.125 mg/mL, 0.088 mg/mL, 0.075 mg/mL, 0.05 mg/mL, 0.025 mg/mL, 0.013 mg/mL, 0.04 mg/mL, 0.02 mg/mL, 0.0375 mg/mL, 0.0625 mg/mL, 0.044 mg/mL
, Oral, Tablet, Tablet - Oral, Topical, Tablet - Topical, Intravenous, Liquid, Liquid - Intravenous, Intramuscular; Intravenous, Powder, for solution, Powder, for solution - Intramuscular; Intravenous, Injection, powder, lyophilized, for solution, Injection, powder, lyophilized, for solution - Intravenous, Capsule, Capsule - Oral, Solution, Solution - Oral, Injection - Intravenous, Injection, Injection, solution, Injection, solution - Intravenous, Solution - Intramuscular; Intravenous

Warnings

Synthroid Contraindications
Condition
Risk Level
Notes
Pulse Frequency
Do Not Combine
Heart Attack
Do Not Combine
Thyrotoxicosis
Do Not Combine
Adrenal gland hypofunction
Do Not Combine
There are 20 known major drug interactions with Synthroid.
Common Synthroid Drug Interactions
Drug Name
Risk Level
Description
Abemaciclib
Major
The serum concentration of Abemaciclib can be decreased when it is combined with Levothyroxine.
Bendamustine
Major
The serum concentration of Bendamustine can be decreased when it is combined with Levothyroxine.
Berotralstat
Major
The serum concentration of Berotralstat can be decreased when it is combined with Levothyroxine.
Binimetinib
Major
The serum concentration of Binimetinib can be decreased when it is combined with Levothyroxine.
Bortezomib
Major
The serum concentration of Bortezomib can be decreased when it is combined with Levothyroxine.
Synthroid Toxicity & Overdose RiskIn rats, the lowest dose of a drug that has been found to cause death was 20mg/kg when taken orally. This has been known to cause a state of hypermetabolism similar to an overactive thyroid. Symptoms of this reaction include weight loss, increased appetite, a racing heart, diarrhea, shaking, difficulty sleeping, feeling too hot or feverish, and irregular periods.
image of a doctor in a lab doing drug, clinical research

Synthroid Novel Uses: Which Conditions Have a Clinical Trial Featuring Synthroid?

15 active studies are currently probing the effects of Synthroid in ameliorating Edematous Fibrosclerotic Panniculopathy (Cellulite), Hypothyroidism and Comatose states.
Condition
Clinical Trials
Trial Phases
euthyroid Goitre
0 Actively Recruiting
Hypothyroidism
5 Actively Recruiting
Phase 4, Phase 2, Phase 3, Not Applicable
Comatose
0 Actively Recruiting
Malignant Neoplasms
0 Actively Recruiting
Cellulite
0 Actively Recruiting
Adiposity
5 Actively Recruiting
Not Applicable, Phase 4

Synthroid Reviews: What are patients saying about Synthroid?

5Patient Review
12/13/2018
Synthroid for Underactive Thyroid
The endocrinologist I visited not only helped me with my diabetes, but also discovered that I had an issue with my thyroid. They put me on Synthroid and gradually increased the dosage over 3 months. Now, my TSH is in the normal range.
5Patient Review
10/18/2017
Synthroid for Underactive Thyroid
Synthroid has been a godsend since my thyroid surgery. I've been taking it regularly since January with few issues. The only downside is that I'm still struggling with hair loss and weight gain, but those are both manageable problems.
5Patient Review
5/17/2020
Synthroid for Underactive Thyroid
I've been on Synthroid for over 44 years and it's helped me a lot. I know my lab results always run high, but I feel fine otherwise. It's hard to find a doctor who is willing to treat the "symptoms" instead of relying strictly on lab results, but I'm hopeful that switching to a generic form won't change how I feel currently.
5Patient Review
3/8/2018
Synthroid for Underactive Thyroid
I've been taking this medication for 10 years with no issues, except for some thinning hair. It's kept my thyroid levels in check ever since my radioactive iodine treatment. However, I was switched to a generic brand without knowing, and my thyroid levels dropped significantly as a result. Once I went back to the name brand, everything improved again.
2Patient Review
7/23/2019
Synthroid for Underactive Thyroid
Unfortunately, I had a really severe allergic reaction to using Synthroid. It contains acacia as well as other ingredients that make it unsafe for me to use. In addition, there was no noticeable difference in my thyroid condition after using this treatment.
2Patient Review
7/23/2019
Synthroid for Underactive Thyroid
I had a terrible allergic reaction to the other ingredients in synthroid, like acacia, aluminum, talc and maybe even gluten. I switched to Tirosint which is just pure glycerine and the necessary ingredients--no food dyes or extra junk. It's more effective and much cleaner.
1.7Patient Review
12/30/2017
Synthroid for Underactive Thyroid
I've been taking this for eight years now, and my thyroid stimulating hormone levels have been all over the place. Recently, they shot up to 6.7 after I changed my dosage from 88 to 50. I'm tired all the time, easily annoyed, and my weight has gone up, though I was able to lose 20 pounds when I changed my diet. Plus, my hair has been falling out like crazy lately.
1Patient Review
4/5/2022
Synthroid for Thyroid Cancer
There are a lot of additives in Synthroid, and many people (myself included) are allergic to them.
1Patient Review
4/12/2019
Synthroid for A Progressive Disease of the Thyroid Gland
Since my total thyroidectomy in 2009, I have been dealing with a range of issues including both hypo- and hyper-thyroidism symptoms. This has led to insomnia, pain in my shoulders and neck, agitation, anxiety and depression.
1Patient Review
5/23/2018
Synthroid for Underactive Thyroid
I took this medication for three months and found that it didn't help me sleep at all, even when I halved the dosage.
1Patient Review
1/3/2019
Synthroid for Underactive Thyroid
Since taking this medication, I have experienced hair loss and weight gain without an increase in appetite. Additionally, I am constantly tired and exhausted.
image of drug pills surrounding a glass of water symbolizing drug consumption

Patient Q&A Section about synthroid

These questions and answers are submitted by anonymous patients, and have not been verified by our internal team.

What does Synthroid do to the body?

"The purpose of Synthroid is to replace the amount of Thyroid hormone that your body is unable to produce. Synthroid is a man-made hormone that is identical to the hormone that your Thyroid gland produces. It is important to maintain optimal Thyroid hormone levels in order to avoid any potential health complications."

Answered by AI

Does Synthroid have side effects?

"The text describes some of the symptoms that may be experienced when suffering from an overactive thyroid, which is a condition in which the thyroid gland produces too much of the hormone thyroxine. Symptoms may include fatigue, increased appetite, weight loss, heat intolerance, fever, excessive sweating, headache, hyperactivity, nervousness, anxiety, irritability, emotional lability, insomnia, tremors, muscle weakness, and muscle spasm."

Answered by AI

Does taking Synthroid cause weight gain?

"If you are taking Synthroid, you may experience weight gain due to an increase in appetite. This may cause you to eat more than usual. You may also gain weight if your dose of Synthroid is not high enough for your body's needs."

Answered by AI

What is the difference between levothyroxine & Synthroid?

"Synthroid is levothyroxine, which is used to treat hypothyroidism. It is a human-made thyroxine hormone, but not always interchangeable with each other."

Answered by AI

Clinical Trials for Synthroid

Image of Cleveland Clinic in Cleveland, United States.

Gluten Free Diet for Hashimoto's Disease

Any Age
All Sexes
Cleveland, OH
Hashimoto's thyroiditis is an autoimmune condition that reduces functioning of the thyroid gland and can lead to a substantial decline in quality of life for patients, with impacted patients often describing unremitting brain fog, fatigue/malaise and weight gain leading to difficulty functioning in their jobs and homes. It is the most common cause of hypothyroidism in the U.S. and affects up to 10% of the global population. The typical treatment for Hashimoto's is thyroid hormone replacement with medications such as levothyroxine. However, despite adequate treatment as defined by thyroid hormone levels within the reference range, up to 10% of patients will experience persisting symptoms which can dramatically impair quality of life. While various theories have been postulated for the residual symptoms, several studies indicate that they are related to the thyroid autoimmunity, specifically the autoantibodies that are made by the immune system in Hashimoto's thyroiditis in response to the thyroid (ie thyroid peroxidase \[TPO\], thyroglobulin \[Tg\] antibody \[AB\]) and the associated inflammation with the immune response. Removal of thyroid (ie total thyroidectomy) reduces levels of these thyroid antibodies and results in significant improvement in quality-of-life. However, thyroidectomy is an invasive procedure with potential for morbidity such as damage to the recurrent laryngeal (nerve that controls the vocal cords and thus speech), bleeding and infection, so there is interest in other more conservative modalities for lowering the inflammation and autoimmune burden in Hashimoto's thyroiditis. In an effort to identify a less invasive approach for reducing the levels of thyroid antibodies and inflammation, attention has moved to the intersection of Hashimoto's thyroiditis and the gut. Hashimoto's has a strong association with autoimmune disorders impacting the gastrointestinal tract, in particular celiac disease and non-celiac gluten sensitivity (NCGS). NCGS is a condition where there are intestinal and extra-intestinal symptoms associated the consumption of gluten but no presence of anti-tissue transglutaminase antibodies (anti-tTG) which define Celiac Disease. This connection between Hashimoto's thyroiditis and sensitivity to gluten appears to be not only genetic, as those with Celiac Disease/NCGS and Hashimoto's thyroiditis have common HLA haplotypes, but also at the level of the intestine with gut microbiome dysfunction.
Recruiting
Has No Placebo
Cleveland Clinic
Image of UConn Health in Farmington, United States.

Novel Treatments for Hypothyroidism

18+
All Sexes
Farmington, CT
Hypothyroidism is a common condition, more frequent in females, associated with excess of cardiovascular risk and poor quality of life not completely abrogated by treatment with levothyroxine. There is an unmet need to define a safe, effective, and feasible regimen to be applied in large trials aimed at assessing levothyroxine/liothyronine combination therapy in patients living with hypothyroidism. To address this knowledge gap we propose a randomized, three-arm, double-blind, controlled, escalating dose parallel pilot study whose results will lay the foundation of large multicenter trial(s) able to demonstrate the effectiveness (or lack thereof) of levothyroxine/liothyronine combination therapy.
Phase 2 & 3
Recruiting
UConn HealthFrancesco Celi
Have you considered Synthroid clinical trials? We made a collection of clinical trials featuring Synthroid, we think they might fit your search criteria.Go to Trials
Image of University of Colorado Anschutz Medical Campus in Aurora, United States.

Estradiol Patch for Menopause

20 - 45
Female
Aurora, CO
The menopause transition is associated with a decrease in artery health and an increased risk for weight gain in storing fat in the stomach area which may increase the risk for heart disease. The purpose of this research is to study how the decrease in estrogen at menopause changes artery health and fat gain, and risk of disease in women as they age. The first aim in this study will determine whether short term and long term low estrogen levels in premenopausal women decreases artery function and whether this is related to an increase in fat in the stomach area. The second aim will determine whether the changes in artery health and body fat are related to changes in a pathway that breaks down an important amino acid called tryptophan. This pathway is thought to play a role in regulating the aging process. Therefore, the investigators will determine whether the decrease in artery health and the increase in body fat in the stomach region with low estrogen is related to changes in this pathway in the blood, in vascular cells and fat tissue. Because estrogen levels fluctuate in premenopausal women, the investigators will use an approach (intervention) that controls estrogen levels to address these aims. The investigators will use a medication that is typically used to treat endometriosis or uterine fibroids to lower estrogen levels and an estrogen patch to increase estrogen in some women. Some women will receive a patch that has no estrogen (called a placebo patch). The intervention period will be 20 weeks. The study will provide us with new knowledge on how low estrogen with menopause affects artery health and fat gain estrogen.
Phase 4
Recruiting
University of Colorado Anschutz Medical CampusKerrie Moreau, PhD
Image of University of Colorado Anschutz in Aurora, United States.

Weight Loss for Obesity

18 - 70
All Sexes
Aurora, CO
The goal of this intervention study is to learn about how weight loss impacts molecular signaling of intermuscular adipose tissue (IMAT) in individuals with obesity. The main question it aims to answer is how inflammatory molecules secreted by IMAT promote muscle insulin resistance and inflammation, and how these same molecules are diminished after weight loss. Following screening visits involving body composition measures, blood testing, strength testing, and a thigh muscle biopsy, participants will go through a 12-week dietary intervention for weight loss. After 12 weeks, this will be followed by the same testing and biopsies that were completed before the intervention. Researchers will then compare outcomes of individuals who lost weight to individuals who did not lose weight.
Recruiting
Has No Placebo
University of Colorado Anschutz
Have you considered Synthroid clinical trials? We made a collection of clinical trials featuring Synthroid, we think they might fit your search criteria.Go to Trials
Unbiased ResultsWe believe in providing patients with all the options.
Your Data Stays Your DataWe only share your information with the clinical trials you're trying to access.
Verified Trials OnlyAll of our trials are run by licensed doctors, researchers, and healthcare companies.
Terms of Service·Privacy Policy·Cookies·Security