Its range of symptoms includes: sudden weight loss increased appetite anxiety, irritability, and nervousness mood changes difficulty sleeping feeling hot sweating fast heartbeat or pounding heart fatigue or tiredness muscle weakness hand tremor or slight shaking more frequent or other changes in bowel movements skin thinning fine, brittle hair menstruation changes enlarged thyroid gland (goiter) swelling at base of your neck eye changes red, thick skin on upper feet and shins Standard treatment for hyperthyroidism Treatment is necessary if you have hyperthyroidism.