Can liothyronine be taken even when thyroid levels are normal?

Yes, but why???: Hi. Sure, most people with normal thyroid function could take a low dose of liothyronine (T3) without it causing hyperthyroidism. The pituitary sees the T3, and secretes TSH accordingly to maintain overall normal exposure to thyroid hormone. But why on earth would you want to do that? In my humble opinion, don't take a hormone you don't need!