Occasionally, hypothyroidism gets better without treatment. In general, however, the symptoms get progressively worse if it isn't treated. Hypothyroidism can be treated with a thyroxine replacement medicine called levothyroxine (also known as L-thyroxine, thyroxine, and T4 — all of these terms refer to the same chemical). This is taken as tablets and it can take some time to get the dose right. Usually you will start on a low dose that's gradually built up every few months. Your GP will adjust your dose according to the results of your blood tests.