Provigil vs Nuvigil aka Modafinil vs Armodafinil (Plain Text Version)

Dosage

Atypical dosage of modafinil is 200 mg verses 150 mg for armodafinil. Patients with narcolepsy can safely take up to 400 mg of modafinil in divided doses (Schwartz, 2003).

Chemistry

Modafinil contains a racemic mixture of R-modafinil (armodafinil) and S-modafinil. Armodafinil is enantiopure (by definition), comprised of 100% the purified stereoisomer Rmodafinil. Technically, you've already tried armodafinil if you've taken modafinil before!

Efficacy

There is little evidence that armodafinil is more effective than modafinil at their indicated dosages. If you're rolling in cash you may want to shell out to get armodafinil instead of modafinil. Otherwise, it's not worth it.

Potency

Armodafinil is a more expensive, purified, and potent form of modafinil that requires a slightly lower dose (150mg vs 200mg).

FDA Approval Timeline

Modafinil was discovered and used clinically prior to the introduction of armodafinil. Modafinil was approved by the FDA in 1998, whereas armodafinil was approved in June, 2007.

Duration and Half-Life

The half-life of both modafinil and armodafinil is roughly '13 hours (Darwish, 2009), though other sources quote a terminal elimination half-life as high as 15 hours.

Effects

Armodafinil and Modafinil have essentially identical effects in the brain, including enhanced wakefulness, vigilance, concentration, and motivation.

References

Darwish M, Kirby M, Hellriegel ET, Robertson P. Armodafinil and modafinil have substantially different pharmacokinetic profiles despite having the same terminal half-lives: analysis of data from three randomized, single-dose, pharmacokinetic studies. Clin Drug Investig. 2009;29(9):613-23.

Darwish M, Kirby M, D'andrea DM, Yang R, Hellriegel ET, Robertson P. Pharmacokinetics of armodafinil and modafinil after single and multiple doses in patients with excessive sleepiness associated with treated obstructive sleep apnea: a randomized, open-label, crossover study. Clin Then 2010;32(12):2074-87.

Bogan RK. Armodafinil in the treatment of excessive sleepiness. Expert Opin Pharmacother. 2010;11(6):993-1002.

Schwartz JR, Feldman NT, Bogan RK, Nelson MT, Hughes RJ. Dosing regimen effects of modafinil for improving daytime wakefulness in patients with narcolepsy. Clin Neuropharmacol. 2003;26(5):252-7.