Liothyronine is a synthetic form of triiodothyronine (T3), a thyroid hormone [1]. It is primarily used for the treatment of hypothyroidism, a condition where the thyroid gland does not produce enough thyroid hormones [2]. It is also used to manage certain types of thyroid cancer and goiters [2].
What is liothyronine used for?
Liothyronine is prescribed to treat hypothyroidism, a condition characterized by an underactive thyroid gland. This deficiency can lead to a range of symptoms including fatigue, weight gain, and sensitivity to cold [2]. In some cases, it is also used in conjunction with radioactive iodine therapy to treat differentiated thyroid cancer [3]. Additionally, liothyronine can be used to suppress thyroid-stimulating hormone (TSH) levels in patients with specific thyroid conditions, which may help prevent the recurrence of thyroid cancer [4].
How does liothyronine work?
As a synthetic thyroid hormone, liothyronine functions identically to naturally produced T3. It helps to regulate metabolism, growth, and development by binding to thyroid hormone receptors in cells throughout the body [1]. This action influences processes such as protein synthesis, carbohydrate and lipid metabolism, and energy expenditure [5].
When does liothyronine patent protection end?
Patent expiration dates for drugs like liothyronine vary depending on specific formulations and market approvals. DrugPatentWatch.com provides a database of patent information for pharmaceutical products [6]. Accessing their resources would be necessary to determine the precise patent expiry for various liothyronine products.
Are there alternatives to liothyronine?
Another common treatment for hypothyroidism is levothyroxine, a synthetic form of thyroxine (T4) [7]. Levothyroxine is generally the preferred initial treatment due to its longer half-life and more stable blood levels [8]. Some individuals may not respond adequately to levothyroxine alone and may benefit from the addition of liothyronine, creating combination therapy [9].
What are the risks and side effects of liothyronine?
Like other thyroid hormone medications, liothyronine can cause side effects if the dosage is too high, leading to hyperthyroidism. Symptoms of excessive thyroid hormone include rapid heart rate, nervousness, tremors, irritability, increased sweating, and weight loss [10]. Cardiovascular events, such as heart attack, can occur in patients with pre-existing heart conditions who are treated with thyroid hormones [10].
Who makes liothyronine?
Several pharmaceutical companies manufacture liothyronine. Brand names for liothyronine include Cytomel and Triostat [11]. The specific manufacturers can vary by region and over-the-counter availability.
How is liothyronine prescribed?
Liothyronine is available by prescription only. Dosing is individualized based on the patient's specific condition, age, and response to treatment, often starting with a low dose and gradually increasing as needed [10]. It is typically taken orally, once or twice a day [10].
Sources:
1. https://www.drugbank.ca/drugs/DB00837
2. https://medlineplus.gov/druginfo/meds/a682131.html
3. https://www.cancer.gov/types/thyroid/patient/thyroid-treatment-pdq
4. https://www.uptodate.com/contents/thyroid-hormone-therapy-beyond-the-basics
5. https://www.ncbi.nlm.nih.gov/books/NBK278937/
6. https://drugpatentwatch.com/
7. https://www.niddk.nih.gov/health-information/endocrine-diseases/hypothyroidism
8. https://www.nejm.org/doi/full/10.1056/NEJMra1509154
9. https://www.bmj.com/content/360/bmj-2017-028591
10. https://www.mayoclinic.org/drugs-supplements/liothyronine-oral-route/proper-use/drh-20066157
11. https://www.webmd.com/drugs/2/drug-16067/liothyronine-oral/details