**9. Treatment approaches**

The main aims of the management of Graves' Disease are to inhibit the overproduction of thyroid hormones by targeting thyroid gland and to alleviate the effect of an excess hormones on various system of the body thereby correct the thyrotoxic state.

The management includes

	- Corticosteroids.
	- Teprotumumab (Tepezza)
	- Prisms.
	- Orbital decompression surgery
	- Orbital radiotherapy

#### **9.1 Radioactive iodine therapy**

The most commonly used therapy for Graves' Disease is radioactive iodine (radioiodine) since the 1940s. It is still popular because it is non-invasive and highly effective on thyroid gland and has fewer side effects. Graves' Disease with a large thyroid gland, multiple symptoms of thyrotoxicosis, high levels of thyroxine, and high titers of TSI are indicated for radioactive iodine and women who are pregnant or breastfeeding are contraindicated for this therapy. Commonly used radioactive iodine is iodine-131 (I-131) and can be administered orally in the form of capsule or liquid. The dose is calculated based on the age, weight of the thyroid gland and radioiodine uptake and the usual dose ranges from 5–15 mCi. Iodine is essential for thyroid gland to produce hormones, the thyroid absorbs the radioiodine into the thyroid cells and the radiation destroys the hyperactive thyroid cells. This causes the thyroid gland to shrink, hormones to return normal and gradually alleviate the symptoms. It usually takes several weeks to several months. Follow up the patient and monitoring the thyroid profile is very important because it causes hypothyroidism.

#### **9.2 Anti-thyroid medications**

Antithyroid medications are one of the prominent methods to treat hyperthyroidism which interfere with the use of iodine by the thyroid to produce hormones. Commonly used antithyroid medicines are thionamides, such as propylthiouracil (PTU), and carbimazole (CBZ). Thionamides are actively transported into the thyroid gland where they inhibit both the organification of iodine to tyrosine residues in thyroglobulin and the coupling of iodotyrosines and hence reduce the synthesis of thyroid hormone [99, 100] and inhibit the function of thyroperoxidase, reducing oxidation and the organification of iodide. Anti-thyroid drugs may be administered before or after radioiodine therapy as a supplemental treatment. Methimazole is considered the first choice of antithyroid medicnes as the risk of

#### *Graves' Disease: Clinical Significance and Management DOI: http://dx.doi.org/10.5772/intechopen.96418*

liver disease is common in Propylthiouracil. However, propylthiouracil is the preferred anti-thyroid drug during the first trimester of pregnancy, as methimazole has a slight risk of birth defects and can continue the methimazole after the first trimester. Side effects of anti-thyroid drugs are allergic reactions such as skin rash, itching, lower resistance to infection due to decrease in white blood cells and rarely liver disease.

#### **9.3 Beta blockers**

Beta blockers do not have the direct effect on thyroid gland to reduce the hormone secretion but can minimize the symptoms until the effect other treatments occur. Beta-blockers, such as propranolol and metoprolol, are often the first line of treatment. The action of beta blockers in hyperthyroidism is to antagonize betareceptor-mediated effects of catecholamines thereby reduce the heart rate, blood pressure, tremors, anxiety or irritability, heat intolerance, sweating, diarrhea, and muscle weakness. Beta blockers may trigger an asthma attack so aren't often prescribed for people with asthma and also complicate management of diabetes.

#### **9.4 Thyroid surgery**

Removal of part or total tissue of thyroid gland namely subtotal or total thyroidectomy is another option for the management of Graves' Disease. Surgery is less common and it is indicated when other treatment fails to manage. Pre-operatively, reduce the size of thyroid gland and bring to the euthyroidal state to reduce the risk of complications post-operatively. The complications of thyroidectomy include hypothyroidism, hypoparathyroidism, recurrent laryngeal nerve, hemorrhage. Patient undergone thyroidectomy has to receive the thyroid replacement hormone medication such as levothyroxine in remaining life.

#### **9.5 Treating Graves' ophthalmopathy**

#### *9.5.1 Over-the-counter artificial tears*

Mild symptoms of Graves' ophthalmopathy may be managed by using over-thecounter artificial tears during the day and lubricating paraffin-based gels can be applied at night.

If symptoms are more severe:

#### *9.5.2 Corticosteroids*

Corticosteroids, such as prednisone, may lessen swelling behind eyeballs. Side effects may include fluid retention, weight gain, elevated blood sugar levels, increased blood pressure and mood swings.

#### *9.5.3 Teprotumumab (Tepezza)*

It's given through an IV in the arm every three weeks and is given eight times. TEPEZZA targets and blocks IGF-1R and inhibits fibroblast activation via the IGF-1R/TSHR signaling complex at the source of the disease [101, 102] and decreases proptosis by [103–105] by reducing inflammation, preventing muscle and fat tissue remodeling, and preventing tissue expansion behind the eye. It can cause side effects such as nausea, diarrhea, muscle spasms and elevated blood sugar levels.

### *9.5.4 Prisms*

Prisms in eye glasses may correct the double vision as double vision is one of the effects of Graves' Disease.

#### *9.5.5 Orbital decompression surgery*

Removal of bone between eye socket (orbit) and sinuses, the air spaces next to the orbit. This decompression moves the eye back to their original position to release pressure on the optic nerve. This treatment is indicated if pressure on the optic nerve threatens the vision and treats the possible complication of double vision.
