Keep snacks handy. Have snacks readily available so that you can eat when you're up to it.
Cheese, ice cream, canned fruit in heavy syrup, dried fruit, nuts, peanut butter with crackers, cheese with crackers, muffins, cottage cheese and chocolate milk are examples of high-calorie snacks requiring little or no preparation.
Don't be too concerned that some of these options are high in cholesterol or fat. Once you regain your appetite, you can focus on lower calorie snacking options.