Are High Liver Enzymes Caused By Levothyroxine?

This review examines the frequency of elevated liver function tests in patients with newly diagnosed and untreated hyperthyroidism. High doses of levothyroxine and other thyroid preparations can cause serum enzyme elevations, typically in a hepatocellular or mixed pattern. Spontaneous hyperthyroidism can be accompanied by serum enzyme elevations and even jaundice.

Levothyroxine-induced liver injury is a rare and reversible adverse effect, and clinical vigilance is required when initiating the drug. After cessation of levothyroxine, liver enzymes gradually returned to normal. People with hypothyroidism have a significant increase in AST and ALT, and it appears that TSH is positively associated with ALT and AST.

A 49-year-old woman with hypothyroidism developed liver dysfunction after increasing the dose of levothyroxine (L-T4) (Euthyrox®) from 25 μg to 50 μg. Supra-physiological thyroid hormone levels did not induce clinically relevant increases in markers of liver injury after 2 weeks of exposure.

In conclusion, high thyroid hormone levels can lead to increased liver function tests in patients with newly diagnosed and untreated hyperthyroidism. It is important to be cautious when initiating the drug and to monitor liver enzyme levels to prevent potential complications.

What is a common adverse effect of levothyroxine?

Levothyroxine may cause serious or life-threatening problems when given in large doses, especially when taken with amphetamines such as amphetamine (Adzenys, Dyanavel XR, Evekeo), dextroamphetamine (Dexedrine), and methamphetamine (Desoxyn). Tell your doctor if you have any of the following symptoms while you are taking levothyroxine: chest pain, rapid or irregular heartbeat or pulse, uncontrollable shaking of a part of the body, nervousness, anxiety, irritability, difficulty falling asleep or staying asleep, shortness of breath, or excessive sweating.

Talk to your doctor about the potential risks associated with this medication.

Levothyroxine is used to treat hypothyroidism (condition where the thyroid gland does not produce enough thyroid hormone). It is also used with surgery and radioactive iodine therapy to treat thyroid cancer. Levothyroxine is in a class of medications called hormones. It works by replacing thyroid hormone that is normally produced by the body.

Can hypothyroidism cause high liver enzymes?

Additionally, the prevalence of NAFLD and abnormal liver enzyme levels (ALT, which is defined as greater than 33/25 IU/L) progressively increased as the grade of hypothyroidism increased.

Can thyroxine cause fatty liver?

Abstract. Levothyroxine or l-thyroxine is artificially manufactured thyroxine, which is used as a drug to treat underactive thyroid conditions in humans. The drug, levothyroxine, is consumed daily in a prescribed dose to replace the missing thyroid hormone thyroxine in an individual with an underactive thyroid, and it helps to maintain normal physiological conditions. Though it is a life-maintaining drug, it replaces the missing thyroid hormone and performs the necessary daily metabolic functions in our body. Like all other allopathic drugs, it comes with certain side effects, which include joint pain, cramps in muscle, weight gain/loss, hair loss, etc. The thyroid hormone, thyroxine, is known to mobilize fat in our body, including the ones from the hepatic system. An underactive thyroid may cause an accumulation of fat in the liver, leading to a fatty liver, which is clinically termed Non-Alcoholic Fatty Liver Disease (NAFLD). The correlation between hypothyroidism and NAFLD is now well-studied and recognized. As levothyroxine performs the functions of the missing thyroxine, it is anticipated, based on certain preliminary studies, that the drug helps to mobilize hepatic fat and thus may have a crucial role in mitigating the condition of NAFDL.

Keywords: Levothyroxine; Subclinical hypothyroidism.; cirrhosis; hepatic carcinoma; non-alcoholic fatty liver disease; thyroxine; triglycerides.

Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience. net.

What is the long term risk of levothyroxine?

Yes, it’s safe to take levothyroxine for a long time, even many years. However, high doses of levothyroxine over a long time can sometimes cause weakening of the bones (osteoporosis).

This should not happen if you are on the right dose. It’s important to have regular blood tests to make sure your dose is not too high.

There’s no evidence to suggest that taking levothyroxine reduces fertility in either men or women.

However, speak to a pharmacist or your doctor if you’re trying to get pregnant as they may want to review your treatment.

What would cause high liver enzymes?

Common causes of elevated liver enzymes include:Nonprescription pain medicines, particularly acetaminophen (Tylenol, others). Certain prescription medicines, including statins, which are used to control cholesterol. Drinking alcohol. Heart failure. Hepatitis A. Hepatitis B. Hepatitis C. Nonalcoholic fatty liver disease.

What thyroid medication is used for fatty liver?

Rezdiffra, made by Madrigal Pharmaceuticals, is a daily pill that activates a thyroid hormone receptor that reduces liver fat accumulation.

Results from an ongoing Phase III clinical trial were published in The New England Journal of Medicine. Resmetirom, which was tested at two dose strengths, was shown to resolve NASH without a worsening of fibrosis in 26% (at the lower dose) and 30% (at the higher dose) of patients compared to 10% in the placebo group. The trial also showed that the drug improved fibrosis by at least one stage in 24% (at the lower dose) and 26% (at the higher dose) of the patients, compared to 14% in the placebo group.

The medication was granted accelerated approval; final approval is contingent on the results of the ongoing study.

What organs are affected by thyroxine?

Thyroxine is the main hormone secreted into the bloodstream by the thyroid gland. It is the less active form of thyroid hormone and most of it is converted to a more active form called triiodothyronine (T3) by local tissues including the liver, kidneys, skeletal and heart muscles, central nervous system, skin, etc.

Alternative names for thyroxine. T4; tetraiodothyronine; thyroxin. The manufactured form used for thyroid hormone replacement is called L-thyroxine or Levothyroxine.

What is thyroxine?. Thyroxine is the main hormone secreted into the bloodstream by the thyroid gland. It is the less active form of thyroid hormone and most of it is converted to a more active form called triiodothyronine (T3) by local tissues including the liver, kidneys, skeletal and heart muscles, central nervous system, skin, etc. Thyroid hormones play vital roles in regulating the body’s metabolic rate, heart, digestive function, muscle control, brain development and maintenance of bones.

How is thyroxine controlled?. The production and release of thyroid hormones, thyroxine (T4) and triiodothyronine (T3), is controlled by a feedback loop system that involves the hypothalamus in the brain and the pituitary and thyroid glands. The hypothalamus secretes thyrotropin-releasing hormone which, in turn, stimulates the pituitary gland to produce thyroid stimulating hormone (TSH). This hormone stimulates the production of the thyroid hormones, thyroxine (T4) and triiodothyronine (T3), by the thyroid gland.

What is the greatest risk of levothyroxine?

Can levothyroxine cause cancer?. Studies have found that taking levothyroxine long-term is associated with a slightly increased cancer risk in both men and women, including an increased risk of breast cancer, lung cancer, gastrointestinal cancers (stomach, colon, liver, pancreas), urinary bladder, skin, and thyroid cancer.

Note: If your thyroid gland has been surgically removed (thyroidectomy) as a treatment for thyroid cancer, your body will no longer make thyroid hormones, and you will need to take thyroid hormone replacement (levothyroxine) to maintain normal thyroid function.

Is it safe to take levothyroxine long term?. It is generally safe to take levothyroxine long-term as prescribed by a doctor. Hypothyroidism is a lifelong condition, so you will likely need to take levothyroxine for life. Your doctor will prescribe the lowest dose of levothyroxine to control your symptoms. Follow your doctor’s dosing instructions carefully and keep all your medical and lab appointments during levothyroxine treatment.

What are the symptoms of too much levothyroxine in your system?

There are many risks of taking too much levothyroxine. The signs and symptoms of thyroid overmedication include anxiety, diarrhea, depression, elevated heartbeat, elevated blood pressure, fatigue, irritability, difficulty concentrating, difficulty sleeping, being overheated, and unprompted or unintentional weight loss.

What does thyroxine do in the liver?

Thyroxine and tri‐iodothyronine are essential for normal organ growth, development and function. These hormones regulate the basal metabolic rate of all cells, including hepatocytes, and thereby modulate hepatic function; the liver in turn metabolizes the thyroid hormones and regulates their systemic endocrine effects. Thyroid dysfunction may perturb liver function, liver disease modulates thyroid hormone metabolism, and a variety of systemic diseases affect both organs. We highlight the intricate relations between the thyroid gland and the liver in health and disease.

• Metabolism
• liver diseases
• thyroid hormones
• thyroid diseases
• liver
• thyroid
• liver function

Can levothyroxine affect the liver?

Conclusion. This case report provides a few learning points. Levothyroxine-induced liver injury is a rare and reversible adverse effect. Clinical vigilance is required when initiating the drug. Triiodothyronine is an appropriate alternative to levothyroxine in treating such cases. Invasive procedures such as liver biopsy were not required to support the diagnosis in our patient’s case. The exact mechanisms of how levothyroxine causes liver injury require further research.

Availability of data and materials. All the investigation results and reports are available on request.

Kawakami T, Tanaka A, Negoro S, et al. Liver injury induced by levothyroxine in a patient with primary hypothyroidism. Intern Med. 2007;46:1105–8.