Yes, Sunosi (solriamfetol) is a Schedule IV controlled substance under the Controlled Substances Act. The DEA placed it in this category in June 2019, shortly after the FDA approved it, based on evidence that it carries a low potential for abuse and limited risk of dependence.
What Schedule IV Means
The DEA uses five schedules to classify controlled substances, with Schedule I being the most restrictive and Schedule V the least. Schedule IV sits near the lower end of that scale. Drugs in this category have a recognized medical use and a low abuse potential relative to Schedule III substances. Other well-known Schedule IV medications include certain sleep aids and anti-anxiety drugs.
For Sunosi specifically, the DEA concluded that it has abuse potential similar to phentermine, a weight-loss stimulant also classified as Schedule IV. In a head-to-head abuse liability study, participants rated their “liking” of solriamfetol significantly lower than phentermine at equivalent test doses. Participants also reported less willingness to take solriamfetol again compared to phentermine. At higher experimental doses, solriamfetol actually produced more negative effects like anxiety and feeling bad, which further limits its appeal for misuse.
How Prescription Rules Apply
Because Sunosi is Schedule IV, your prescription comes with specific federal limits. It can be refilled up to five times, and it expires six months after the date it was written. After that, your prescriber needs to issue a new prescription. These rules apply to all Schedule III and IV medications.
Unlike Schedule II stimulants such as amphetamines, Sunosi does not require a new prescription for every fill, and your doctor can call or electronically transmit the prescription to your pharmacy. This makes the refill process noticeably more convenient than what patients on higher-schedule stimulants experience.
Why It Has a Lower Abuse Risk Than Traditional Stimulants
Sunosi works by blocking the reabsorption of two brain chemicals, dopamine and norepinephrine, which keeps more of them active in the spaces between neurons. This increases wakefulness. The key distinction is what it does not do: unlike amphetamines, Sunosi does not force neurons to release extra dopamine or norepinephrine. That releasing action is what gives traditional stimulants their stronger euphoric effect and higher abuse potential.
Sunosi also has no meaningful effect on serotonin and doesn’t interact with histamine receptors, nicotine receptors, or GABA receptors. Its pharmacological footprint is relatively narrow, which contributes to both its lower abuse risk and its more limited side effect profile compared to broader-acting stimulants.
In animal studies, rats and dogs showed no signs of physical dependence after abruptly stopping solriamfetol. Human clinical trials found no consistent pattern of withdrawal symptoms either, though some participants did report various adverse effects after discontinuation. The overall picture points to a risk of limited psychological dependence at most.
What Sunosi Is Prescribed For
Sunosi is FDA-approved to improve wakefulness in adults with excessive daytime sleepiness caused by narcolepsy or obstructive sleep apnea. For obstructive sleep apnea, it is not a replacement for treatments that keep the airway open, like CPAP. The FDA label requires that the underlying airway obstruction be treated for at least one month before starting Sunosi, and that those treatments continue alongside it.
Side Effects Worth Knowing About
The most clinically significant concern with Sunosi is its effect on cardiovascular function. It raises systolic blood pressure, diastolic blood pressure, and heart rate in a dose-dependent way, meaning higher doses produce larger increases. Your blood pressure should be checked and any existing hypertension controlled before you start the medication. Regular blood pressure monitoring continues throughout treatment.
Psychiatric side effects have also been reported in clinical trials, including anxiety, insomnia, and irritability. People with a history of psychosis or bipolar disorder should be aware that Sunosi has not been formally studied in those populations. If new psychiatric symptoms appear during treatment, a dose reduction or discontinuation may be appropriate.
International Classification
In the European Union, Sunosi is available only by prescription and is designated for “additional monitoring,” a status the European Medicines Agency assigns to newer drugs that warrant closer post-market surveillance. While the EU does not use the same scheduling system as the United States, the prescription-only requirement and additional monitoring reflect a similar level of regulatory caution around its use.