Modalert 200mg is not regarded as a large dosage; in fact, it is the usual standard amount that physicians recommend for ailments including narcolepsy, shift work sleep disorder, or drowsiness associated with obstructive sleep apnea. To encourage alertness, most individuals take 100–200 mg once a day in the morning. To determine their tolerance, some people begin with 100 mg and increase if necessary. Even though 200 mg is a usual dosage, sensitivity varies, so adverse effects, including headache, anxiety, or sleeplessness are possible, particularly if taken late in the day. Always heed the advice of your doctor.