Thyroid Two common types of thyroid dysfunction are Hypothyroidism : where the thyroid gland is under active & Hyperthyroidism : where the thyroid gland is over active HYPERTHYROIDISM SYMPTOMS: Anxiety, nervousness & irritability Changes in menstrual cycle including lighter bleeding & less frequent periods Weight loss despite increased appetite Trembling & sweating Frequent bowel movements Difficulty sleeping Hair turns brittle & thin Weakness of muscle esp in thigh & upper arms Rapid heart beat usually over 100 beats per minute.