(Generic) L-thyroxine provides thyroid replacement therapy in all conditions of inadequate production of thyroid hormones. Each L-thyroxine (Levothyroxine Sodium, USP) Tablet provides synthetic crystalline levothyroxine sodium (L-thyroxine). The initial recommended dose is for L-thyroxine is 0.1 mg/10 lb body weight twice daily. The usual maintenance dose is 0.1 mg/10 lb once daily. Generic equivalent to Soloxine. L-thyroxine.