Generally, there is no way to reverse the damage done to the thyroid gland. The healthcare provider will prescribe thyroid hormone, such as levothyroxine or liothyronine, to be taken on a daily basis. The right dose of medication should resolve the signs and symptoms of hypothyroidism.
If a person has had hypothyroidism for many years, the replacement of thyroid hormone may be started slowly and eventually increased to normal levels. Because the thyroid hormone medication is chemically identical to the body's thyroid hormone, side effects or allergic reactions to the medications are quite rare.
If too much thyroid hormone is given, the person may develop arrhythmias, or irregular heartbeats, and osteoporosis, or thinning of the bones.
Treatment of hypothyroidism is lifelong.
The healthcare provider will use periodic thyroid function tests to monitor the level of medication needed. These blood tests may initially be done every 6 to 8 weeks, until a normal level of thyroid is restored. After the right dose of medication is established, thyroid function tests may then be done every 6 to 12 months. Any new or worsening symptoms should be reported to the healthcare provider.