Symptoms of hyperthyroidism in children include:

   Similar to adult symptoms
   Declining school performance
   Behavior problems

  Symptoms of hyperthyroidism in adults include:

   Insomnia
   Hand tremors
   Nervousness
   Feeling excessively hot in normal or cold temperatures
   Frequent bowel movements
   Losing weight despite normal or increased appetite
   Excessive sweating
   Menstrual period becomes scant, or ceases altogether
   Joint pains
   Difficulty concentrating
   Eyes seem to be enlarging

  Symptoms of hyperthyroidism in the elderly may cause:

   Worsening of angina (chest pain) in persons with heart disease
   Worsening of shortness of breath in persons with heart failure
   Muscle weakness, especially in the shoulders and thighs