Modafinil comes as a tablet to take by mouth. It is usually taken once a day with or without food. If you are taking modafinil to treat narcolepsy or OSAHS, you will probably take it in the morning. If you are taking modafinil to treat shift work sleep disorder, you will probably take it 1 hour before the beginning of your work shift. Take modafinil at the same time every day.