Synthetic thyroid hormone such as Synthroid and Tirosint only includes thyroxine, also known as T4. On the other hand, natural thyroid hormone includes both T3 and T4, along with small amounts of T1, T2, and calcitonin. But why is this important?
https://www.rxlist.com/armour_thyroid_vs_np_thyroid/drugs-condition.htm
Changes in appetite changes in menstrual periods chest pain diarrhea fast or irregular heartbeat fever hand tremors headache irritability leg cramps More items...
https://www.webmd.com/drugs/2/drug-18006/nature-throid-oral/details/list-sideeffects
While Synthroid is the most popular form of synthetic thyroid hormone medication, there definitely are better options, such as Tirosint.
https://www.restartmed.com/tirosint/
You are right that it is more expensive than the generic medication. Synthroid runs between $45 and $67 for 30 pills. The generic version costs between $12 and $16 for the same 30 tablets. That’s why many insurance companies only want to pay for generic levothyroxine.
https://www.peoplespharmacy.com/articles/can-you-get-brand-name-synthroid-at-a-reasonable-price
pdf for "nature thyroid vs synthroid".(Page 1 of about 16 results)