Liquefy your assets. When you're hot, your body perspires to cool you down. But if you lose too much water—as you might with a high fever—your body turns off its sweat ducts to forestall further water loss.
Fruit and vegetable juices. These are high in vitamins and minerals.
Ice. If you're too nauseated to drink, you can suck on ice.
Decrease your caffeine intake, avoid alcohol, and stop smoking.
As a fever subsides, the appetite usually returns. When it does, start by eating diluted vegetable juices or vegetable soups. In general, cooked foods are easier to digest than raw ones. Simple foods such as whole grains, steamed vegetables, soup and diluted juices are recommended for a few days after a fever or until strength has returned.