Modafinil improves wakefulness in adults with excessive sleepiness associated with narcolepsy, obstructive sleep apnoea and shift-work sleep disorder.

Usually taken once in the morning, or one hour before a work shift. Modafinil is not a substitute for adequate sleep.

Common: headache, nausea, nervousness, insomnia. Stop immediately and seek care for any rash — serious skin reactions have been reported.

Can reduce the effectiveness of hormonal contraception. Report chest pain or psychiatric symptoms. Not for treating general tiredness.