Solriamfetol (Sunosi) Treatment Protocol for Adults with Excessive Daytime Sleepiness
Solriamfetol is strongly recommended as a first-line treatment for adults with excessive daytime sleepiness due to narcolepsy and can be effectively used for obstructive sleep apnea (OSA) with appropriate dosing protocols. 1
Indications and Mechanism
Solriamfetol (Sunosi) is a dopamine and norepinephrine reuptake inhibitor (DNRI) specifically indicated for improving wakefulness in adults with excessive daytime sleepiness associated with:
- Narcolepsy (strong recommendation)
- Obstructive sleep apnea (OSA)
For OSA patients: Solriamfetol is not a treatment for the underlying airway obstruction and should only be initiated after at least one month of primary OSA treatment (e.g., CPAP) 2
Dosing Protocol
For Narcolepsy:
- Starting dose: 75 mg once daily upon awakening
- May increase to 150 mg once daily after at least 3 days if needed
- Maximum dose: 150 mg once daily 1, 2
For OSA:
- Starting dose: 37.5 mg once daily upon awakening
- May increase to 75 mg once daily after at least 3 days if needed
- May further increase to 150 mg once daily if needed
- Maximum dose: 150 mg once daily 2
Administration Timing:
- Administer once daily upon awakening
- Avoid administration within 9 hours of planned bedtime to prevent interference with sleep 2
Dose Adjustments for Renal Impairment:
- Moderate impairment: Start with 37.5 mg once daily; may increase to 75 mg after at least 7 days
- Severe impairment: 37.5 mg once daily (maximum dose)
- End-stage renal disease: Not recommended 2
Titration Strategy
- Most patients require only one dose adjustment to reach a stable dose
- Median time to reach stable dose: 14 days (range 1-74 days)
- For narcolepsy: Most patients initiate at 75 mg/day and stabilize at 150 mg/day (76%) 3
- For OSA: Most patients initiate at either 37.5 mg/day (48%) or 75 mg/day (48%) and stabilize at either 75 mg/day (56%) or 150 mg/day (40%) 4
When Transitioning from Other Medications
- Wake-promoting agents (e.g., modafinil, armodafinil): Most physicians (64-94%) discontinue these abruptly when switching to solriamfetol
- Stimulants (e.g., amphetamines): Most physicians (56-67%) taper these medications when transitioning to solriamfetol
- Primary reason for switching to solriamfetol: Better efficacy profile (58-63% of cases) 4, 3
Monitoring and Safety
Before Initiating:
- Measure baseline blood pressure and heart rate
- Screen for history of psychosis or bipolar disorders
- Ensure adequate treatment of underlying OSA for at least one month (if applicable)
During Treatment:
- Monitor blood pressure and heart rate periodically
- Watch for psychiatric symptoms, especially in patients with history of psychosis or bipolar disorders
- Consider dose reduction or discontinuation if psychiatric symptoms develop 2
Common Adverse Events:
- Headache, decreased appetite, insomnia, anxiety, nausea (≥5% incidence)
- Most adverse events occur within 2 weeks of treatment initiation and resolve within 2 weeks 2, 5
- Adverse events are typically mild to moderate in severity 1
Contraindications and Precautions
- Contraindicated with concurrent MAOI use or within 14 days of MAOI use
- Use with caution in patients with:
- Unstable cardiovascular disease
- Serious heart arrhythmias
- Other serious heart problems
- History of psychosis or bipolar disorders
- Pregnancy: Animal data suggest potential fetal harm; insufficient human data 1, 2
Expected Outcomes and Benefits
- Significant improvements in:
- Mean sleep latency (objective measure of wakefulness)
- Epworth Sleepiness Scale scores (subjective measure of sleepiness)
- Functional status and quality of life
- Work productivity (25% or greater improvement)
- Benefits are typically sustained for up to 52 weeks of treatment 6, 7
Special Considerations
- Solriamfetol is a Schedule IV controlled substance with potential for abuse or dependency
- Drug interactions: Use caution when co-administering with medications that increase blood pressure/heart rate or with dopaminergic drugs
- For OSA patients: Continue primary OSA treatment (e.g., CPAP) during solriamfetol therapy 2
Solriamfetol represents an effective treatment option with high-quality evidence supporting its use for excessive daytime sleepiness in adults with narcolepsy or OSA, with benefits that are sustained long-term and a manageable safety profile.