Modafinil (Provigil)

Modafinil (Trade name: Provigil) is a/an wakefulness-promoting agent and CNS stimulant. It is commonly used in the treatment of sleep disorders such as narcolepsy and daytime fatigue in obstructive sleep apnea.

Pharmacokinetics of Modafinil

Modafinil: Cytochrome P450 Metabolism

Substrate of (Metabolized by) 3A4
Induces 3A4, 2B6, 1A2
Inhibits 2C19

Dosing for Modafinil

Starting 100mg PO BID (at 0800 and 1200)
Titration Increase by 100 mg
Maximum 200 mg PO BID (maximum total dose 400 mg PO daily)
Taper No tapering required
  • Modafinil comes in oral formulation.
  • Co-administration of modafinil with drugs such as diazepam, phenytoin and propranolol (which are largely eliminated via CYP2C19 pathway), may increase the circulating levels of these drugs.
  • For women of child-bearing age, combined oral contraceptives, transdermal patches, vaginal oral contraceptives, and progesterone contraceptives may be reduced in efficacy when taking modafinil.
    • Copper intrauterine devices, levonorgestrel releasing intrauterine systems, and depot medroxyprogesterone acetate (DMPA) are not affected and should be recommended for women for whom there is this interaction.
  • There is a risk for Stevens-Johnson Syndrome and patients should be counselled on this potential risk.[1]
  • There is an increased risk for major congenital malformations when used during pregnancy.[2]