This is an observational study evaluating patients diagnosed with narcolepsy or idiopathic hypersomnia that have been prescribed a new/different hypersomnia treatment. The study is being done to better understand how hypersomnia treatment(s) impact blood pressure and cognitive function.

This is an observational study evaluating how hypersomnia medications influence blood pressure and cognitive function in patients diagnosed with narcolepsy or idiopathic hypersomnia. Blood pressure will be assessed using 24-hour ambulatory blood pressure monitoring equipment. Cognitive function will be evaluated using the Oculo-Cognitive Addition Test (OCAT). Both tests will performed at baseline (e.g., before starting a new hypersomnia medication) and after taking a stable dose of the new hypersomnia medication for at least three months. All medications will be prescribed by a clinical sleep specialist as part of routine medical care and covered by subject's health insurance plan (i.e., no medications are dispensed/titrated/paid for by the study investigators/trial).

The 24-hour ambulatory blood pressure test will be setup in person by staff. During the blood pressure test, the study participant will also complete a sleep diary and wear an actigraphy watch to track activity and sleep-wake cycle. The 24-hour ambulatory blood pressure test will be programmed to inflate a blood pressure cuff placed around the arm every 15 - 30 minutes.

The OCAT test, which takes approximately 15-20 minutes to complete, will be completed in person as well.

Each study participant may complete one or both tests. Each study participant may complete more than two assessments (e.g., patient that has been prescribed a second hypersomnia medication). If a patient presents already taking a medication of interest at baseline for at least the last 3 months then the participant may undergo baseline assessment(s) while taking respective medication(s).

Inclusion Criteria:

• Diagnosed with narcolepsy or idiopathic hypersomnia according to International Classification of Sleep Disorders, third edition
• Age 18 - 75 years
• BMI between 18 and 40 kg/m2
• Prescribed a medication of interest (e.g., sodium oxybate, low sodium oxybate, pitolisant, modafinil/armodafinil, solriamfetol, traditional stimulant(s)) by a clinical sleep specialist as part of routine medical care.
• Subject must be willing to postpone starting medication until after completion of baseline assessment(s).
• If subject has been taking a prescribed hypersomnia medication(s) at a stable dose for at least 3 months and has been prescribed a new medication, then subject may complete baseline assessment(s) while taking initial hypersomnia medication(s) before starting new medication.

Exclusion Criteria:

• Any change to medication(s) within the last 45 days
• History of chronic alcohol or drug abuse within the prior 12 months
• Heart failure, history of severe hypertension, or other cardiovascular disease compromising the patient's wellbeing or ability to participate in this study
• Use of any sleep apnea treatment (e.g., Positive Airway Pressure (PAP) therapy, oral appliance therapy, etc.) within 45 days of baseline assessment visit
• Participation in another study of an investigational drug within the 28 days prior to screening visit or currently
• Pregnancy and/or breast-feeding
• Subjects who, in the opinion of the Investigator, may not be suitable for the study.

Patients diagnosed with narcolepsy or idiopathic hypersomnia that have been prescribed but not yet started a new/different hypersomnia medication.