I can share with you what my endo told me. He is not impressed by the
generic levothyroxine. He stated the
generic is often manufactured in places like India where the potency range only has to fall between 30-60% effective to be accepted, whereas when Synthroid is manufactured in the USA, its potency has to be 60-95% effective. The generic is often bought from India because it can be bought for pounds of meds on the dollar, whereas in the US it is ounces on the dollar.