Also, eat less sugar. That quick high followed by a quick drop can leave you tired. Try meditation or another form of relaxation. This can be better than sleep for recharging your battery. Some people toss and turn all night and wake up exhausted.
Deep relaxation works better to relieve fatigue.
Take a nap. Keep in mind, however, that others find naps upset their sleep cycle. Like hunger, which signals that your body needs food, fatigue is a signal to slow down, rest and recharge. Remember, fatigue is complex. The more information you can give your doctor, the better advice you're likely to receive.