Sunosi (solriamfetol) and modafinil both improve wakefulness in adults with excessive daytime sleepiness due to narcolepsy or obstructive sleep apnea, but they are supported by different types of clinical evidence. Modafinil is an established wakefulness agent with decades of use and extensive safety guidance, while Sunosi is supported by long-term trials that placed sustained daily functioning and work productivity among their primary measured outcomes. There are no direct head-to-head trials, so differences reflect what each drug has been studied to demonstrate, not proven superiority.
How they improve wakefulness
Modafinil’s exact mechanism of action is not fully established. Clinical and laboratory studies show that it inhibits dopamine reuptake, increasing extracellular dopamine levels, and it has also been observed to influence orexin, histamine, and glutamate signaling pathways involved in alertness. These combined effects promote wakefulness without the pronounced euphoric effects seen with traditional stimulants.
Sunosi is described in clinical trials and labeling as a dopamine and norepinephrine reuptake inhibitor. By increasing activity in these catecholamine pathways, it improves alertness and reduces excessive daytime sleepiness.
Both medications act on neurotransmitter systems related to wakefulness. Neither treats the underlying cause of narcolepsy or obstructive sleep apnea.
Daily functioning and quality of life
The main distinction between the two drugs lies in how consistently broader daily outcomes have been measured over time.
Sunosi has been evaluated in long-term studies lasting up to 40 weeks in some participants and up to 52 weeks in others. These trials assessed not only sleepiness, but also daily functioning, work productivity, and health-related quality of life using validated instruments such as the Functional Outcomes of Sleep Questionnaire and the SF-36. Improvements in these measures were sustained throughout the treatment period.
Modafinil has also been studied long term, and published trials cited in the clinical literature report improvements in fatigue and quality-of-life measures, including SF-36 and functional outcome scales. However, these outcomes have not been as consistently emphasized or uniformly measured across studies as wakefulness itself. As a result, the long-term evidence base for modafinil is broader in duration but less standardized in functional outcome reporting.
Practical use differences
Modafinil is typically taken once daily in the morning, or before a work shift in shift work sleep disorder. It has a long half-life and a gradual onset, contributing to sustained alertness across the day. It is approved for narcolepsy, obstructive sleep apnea related sleepiness, and shift work sleep disorder.
Sunosi is taken once daily in the morning and is approved for excessive daytime sleepiness associated with narcolepsy or obstructive sleep apnea. It is not approved for shift work sleep disorder. Dosing is adjusted based on diagnosis and clinical response.
Safety considerations that matter to patients
Both medications can affect cardiovascular parameters and require similar caution.
Modafinil prescribing information reports increases in blood pressure and heart rate in some patients, along with a higher likelihood of requiring new or intensified antihypertensive treatment compared with placebo. Caution is advised in patients with cardiovascular disease.
Sunosi trials also reported increases in blood pressure and heart rate, and labeling advises caution in patients with underlying cardiovascular conditions. These effects reflect shared risks associated with wakefulness-promoting agents that act on catecholamine systems.
Other modafinil-specific considerations include rare but serious skin reactions, interactions that reduce the effectiveness of hormonal contraceptives, and dose reduction in severe liver disease. Common adverse events reported with Sunosi include headache, nausea, decreased appetite, insomnia, and anxiety.
Neither medication replaces primary therapy for obstructive sleep apnea, such as CPAP.
What remains uncertain
No study has directly compared Sunosi and modafinil in the same patient population. As a result, differences in reported outcomes reflect study design and endpoint selection rather than direct comparative effectiveness.
Bottom line
Modafinil and Sunosi both effectively improve wakefulness in excessive daytime sleepiness. Long-term studies of both drugs report improvements beyond sleepiness alone, including measures of functioning and quality of life. Sunosi’s trials placed these outcomes at the center of long-term evaluation, while modafinil’s evidence base is broader in duration and clinical experience, with functional outcomes reported less consistently. Choosing between them depends on which outcomes are most relevant to the patient and how each medication is tolerated, rather than on evidence of categorical advantage.
Sources
- Greenblatt, K., & Adams, N. (2023). Modafinil. In StatPearls. StatPearls Publishing. https://www.ncbi.nlm.nih.gov/books/NBK531476/
- U.S. Food and Drug Administration. (2015). PROVIGIL® (modafinil) tablets, for oral use, C-IV [Prescribing information]. U.S. Department of Health and Human Services. https://www.accessdata.fda.gov/drugsatfda_docs/label/2015/020717s037s038lbl.pdf
- Weaver, T. E., Pepin, J. L., Schwab, R., Shapiro, C., Hedner, J., Ahmed, M., Foldvary-Schaefer, N., Strollo, P. J., Mayer, G., Sarmiento, K., Baladi, M., Bron, M., Chandler, P., Lee, L., & Malhotra, A. (2021). Long-term effects of solriamfetol on quality of life and work productivity in participants with excessive daytime sleepiness associated with narcolepsy or obstructive sleep apnea. Journal of Clinical Sleep Medicine, 17(10), 1995–2007. https://doi.org/10.5664/jcsm.9384