Modafinil (Provigil) vs Armodafinil (Nuvigil): Racemic Mixture vs Pure R-Enantiomer
Modafinil and Armodafinil are the gold-standard eugeroic (wakefulness-promoting) compounds. Modafinil is a 50/50 racemic mix of two enantiomers. The body metabolizes the S-isomer rapidly within 4 hours, leaving the R-isomer to do the work. Armodafinil contains 100% pure R-enantiomer, giving users a more potent, long-lasting mental stamina boost with fewer dosage peaks and troughs.
Feature-by-Feature Comparison
Modafinil (Provigil)
Armodafinil (Nuvigil)
| Feature / Capability | Modafinil (Provigil) | Armodafinil (Nuvigil) |
|---|---|---|
| Active Isomer | Racemic (R- and S-isomers) | Pure R-enantiomer only |
| Duration of Alertness | 10 to 12 hours | 12 to 15 hours |
| Standard Single Dose | 200mg | 150mg |
| Late-Day Wakefulness | Moderate | Significantly stronger in afternoon |
| Sleep Interference Risk | Moderate if taken late | Higher if taken past 9 AM |
| Generic Available | ||
| Starting Price | $150.00 – $210.00 | $115.00 – $270.00 |
| View Modafinil (Provigil) | View Armodafinil (Nuvigil) |
The Final Verdict
Armodafinil is the refined, isolated R-enantiomer of Modafinil. Because the R-enantiomer stays in the bloodstream up to 3 times longer than the S-enantiomer, a 150mg dose of Armodafinil delivers longer, sharper alertness than a 200mg dose of Modafinil.
Medical Disclaimer
This comparison is for informational purposes only and does not constitute medical advice. The accuracy of pricing and features may change over time. Always consult with a qualified healthcare provider before starting, stopping, or changing any medication.
Last updated: September 2026