The best time to take modafinil is in the morning as its effects last for the next 8-10 hours. Or simply you can take it as prescribed by your doctor. You must follow all the directions mentioned on your prescription label. The usual dose is modafinil 200mg. Avoid taking this medicine in larger or smaller amount than recommended. You might need to consult a specialist as they will need to study your current health report and your medical history to recommend exact dosages. Your doctor will analyze your health and according to your report he/she will suggest you the proper dosage. The recommended dosage of Modafinil is normally dependent on how good your health is and well your body can respond to this medication. As mentioned above, the usual dose prescribed by the doctor is 200mg. For patients with other medical problems, this tablet should be taken only once a day and not more than that. The person should not stop taking this medication all of a sudden. This tablet can be taken with or without food.