Hypothyroidism is due to deficiency of secretion of thyroid hormone from thyroid gland. The most common cause of hypothyroidism is autoimmune thyroiditis in which there is a chronic inflammation of thyroid gland. Other common causes of hypothyroidism include iodine deficiency thyroid gland removal, radioiodine therapy, and drugs such as amiodarone, lithium, thionamide, interferon, sunitinib, rifampicin, and thalidomide. Levothyroxine (Eltroxin is brand name) is the treatment of choice for hypothyroidism. Serum TSH should be measured to monitor for adequate replacement. TSH is measured 6–8 weeks after initiation of levothyroxine and then annually once you are are on a stable dose of levothyroxine. You need to take levothyroxine for life-long. Any interruption in treatment will cause symptoms of hypothyroidism such as fatigue, increased sensitivity to cold, constipation, dry skin, weight gain, puffy face, hoarseness, muscle weakness, elevated blood cholesterol level, muscle aches, tenderness and stiffness, pain, stiffness or swelling in your joints, heavier than normal or irregular menstrual periods, thinning hairs, slowed heart rate, depression, and impaired memory. Common side effects of Eltroxin include fast or irregular heart rate, hot flashes, sweating, sleep problems (insomnia), changes in your menstrual periods, vomiting, diarrhea, appetite changes, weight changes, and mild hair loss. Advice 1. Continue Eltroxin as suggested Thanks