See the DrugPatentWatch profile for synthroid
Synthroid is manufactured by AbbVie [1].
Who Else Sells Levothyroxine?
Levothyroxine, the active ingredient in Synthroid, is available from multiple manufacturers in both brand-name and generic forms. These include companies like Amneal Pharmaceuticals, Teva Pharmaceuticals, and ANI Pharmaceuticals, among others [2]. The availability of different manufacturers means that patients may be prescribed or receive different versions of levothyroxine, which can be a point of discussion with healthcare providers regarding potential differences in formulation or inactive ingredients [3].
How Does Synthroid Work?
Synthroid is a synthetic form of thyroxine (T4), a naturally occurring hormone produced by the thyroid gland. It works by replacing or supplementing the thyroxine that the body is not producing in sufficient amounts [4]. This hormone is crucial for regulating the body's metabolism, impacting energy levels, heart rate, body weight, and temperature [5].
When Does Synthroid's Patent Expire?
The original patents for Synthroid have long expired, allowing for the production of generic levothyroxine. DrugPatentWatch.com tracks patent expirations for pharmaceuticals, indicating that the era of patent exclusivity for the original Synthroid formulation has passed [6]. This has led to the widespread availability of more affordable generic alternatives.
What Are the Side Effects of Synthroid?
Like any medication, Synthroid can cause side effects. These often mirror the symptoms of hyperthyroidism (overactive thyroid) and can include rapid or irregular heartbeat, chest pain, fever, headache, nervousness, irritability, trouble sleeping, tremors, weight loss, increased appetite, diarrhea, vomiting, or sensitivity to heat [7]. Patients are advised to report any concerning side effects to their doctor.
Why Do Doctors Prescribe Synthroid?
Synthroid is primarily prescribed to treat hypothyroidism, a condition where the thyroid gland does not produce enough thyroid hormones [4]. It is also used to treat or suppress an enlarged thyroid gland (goiter) and to manage thyroid cancer [8]. Doctors prescribe it to restore the body's hormone levels, alleviating symptoms associated with an underactive thyroid and supporting overall metabolic function [5].
How Does Synthroid Compare to Other Thyroid Medications?
Synthroid is a brand-name levothyroxine product. Other levothyroxine products, often referred to as generics, contain the same active ingredient but may differ in their inactive ingredients. Some patients may find they tolerate one levothyroxine product better than another due to these inactive ingredients [3]. While other medications exist for thyroid conditions, such as liothyronine (a synthetic T3 hormone) or combination T3/T4 therapies, levothyroxine like Synthroid remains the most common treatment for hypothyroidism [9].
What Are Patient Concerns About Levothyroxine?
Patient concerns often revolve around finding the most effective and consistent formulation of levothyroxine. Some individuals report experiencing symptom fluctuations when switching between different generic manufacturers or even between different lots of the same product. This can lead to discussions with healthcare providers about thyroid hormone level monitoring and potential brand-name prescriptions to ensure consistency [3][10].
Can Biosimilars of Synthroid Be Developed?
As Synthroid is a small molecule drug (a synthetic hormone), the concept of biosimilars, which applies to biologic drugs, is not directly applicable. However, the expiration of its patents has allowed for the widespread development and availability of generic versions of levothyroxine, offering interchangeable options for patients [2][6].
What is the Cost of Synthroid?
The cost of Synthroid can vary significantly depending on insurance coverage, pharmacy, and dosage. Brand-name Synthroid is generally more expensive than its generic counterparts. Generic levothyroxine pills are often very affordable, especially with insurance or through discount programs [11].
Sources:
[1] https://www.drugpatentwatch.com/drug/synthroid
[2] https://www.drugpatentwatch.com/drug/levothyroxine-sodium
[3] https://www.mayoclinic.org/diseases-conditions/hypothyroidism/expert-answers/thyroid-medication/faq-20058320
[4] https://www.mayoclinic.org/drugs-supplements/levothyroxine-oral-route-parenteral-route/description/drg-20067744
[5] https://www.niddk.nih.gov/health-information/endocrine-diseases/hypothyroidism
[6] https://www.drugpatentwatch.com/
[7] https://www.mayoclinic.org/drugs-supplements/levothyroxine-oral-route-parenteral-route/side-effects/drg-20067744
[8] https://medlineplus.gov/druginfo/meds/a682461.html
[9] https://www.endocrineweb.com/conditions/thyroid/thyroid-hormone-treatment-hypothyroidism
[10] https://www.thyroid.org/patient-thyroid-information/ct-for-patients/vol-7-issue-2/vol-7-issue-2-p-4/
[11] https://www.goodrx.com/synthroid