A sleep study, known medically as polysomnography, is a non-invasive, overnight test that records various body functions during sleep, including brain activity, eye movements, breathing, heart rate, and muscle activity. This monitoring provides objective data essential for diagnosing sleep disorders like sleep apnea, narcolepsy, or restless legs syndrome. Proper preparation is paramount because substances or physical barriers can interfere with the sensors, potentially leading to inaccurate results. Following specific guidelines ensures the collected data accurately reflects your body’s behavior during sleep.
Adjusting Your Routine in the Days Leading Up
Preparation for accurate polysomnography results often begins 24 to 48 hours before the scheduled appointment. A critical step is discussing all current medications and supplements—both prescription and over-the-counter—with the referring physician well in advance. Certain drugs, such as stimulants, antidepressants, or even common antihistamines, can significantly alter sleep architecture or breathing patterns, which may skew the test results. The doctor will provide specific instructions on whether to continue, hold, or adjust the dosage; never stop a prescription without this guidance.
On the day of the study, strict adherence to substance avoidance is necessary to prevent artificial disruption of sleep cycles. Avoid all sources of caffeine, including coffee, tea, chocolate, and soft drinks, for at least 12 hours before the study begins. Alcohol must also be completely avoided in the afternoon and evening, as it can suppress REM sleep and relax throat muscles, confounding the diagnosis.
Resist the urge to nap on the day of the study, even if you feel excessively sleepy. The goal is to be sufficiently tired upon arrival to allow for a natural sleep onset during the monitoring period. Napping beforehand can reduce the amount of time spent in certain sleep stages, potentially limiting the diagnostic information gathered.
Preparing Your Body on the Day of the Study
Physical preparation ensures the sensors and electrodes adhere securely and transmit clear signals throughout the night. Before arriving at the sleep facility, you must shower or bathe thoroughly, washing your hair with shampoo. Clean hair and skin are necessary because oils and residue increase the electrical resistance between the skin and the electrode, leading to poor signal quality.
It is essential to avoid applying any hair products after washing, including conditioners, oils, gels, sprays, or creams. These substances leave a residue that prevents the conductive paste from establishing a strong bond with the scalp, where electrodes monitor brain waves. Similarly, do not use heavy lotions, creams, or makeup on your face, neck, or chest. The technician will place sensors on these areas to measure eye movement, heart rhythm, and muscle activity, and a clean surface is required for reliable attachment.
Essential Logistics and What to Pack
The practical aspects of an overnight stay involve gathering necessary items and confirming appointment logistics. Bring required identification, such as a photo ID, your insurance card, and any specific paperwork provided by the facility. Confirm the exact check-in time, as most studies begin in the early evening to allow technicians time for sensor application before bedtime.
For comfort and technical ease, pack comfortable, two-piece sleepwear, such as pajamas or a t-shirt and loose-fitting bottoms. Clothing should not be restrictive or made of slick materials like silk, as technicians need easy access to place sensors.
- Personal toiletries.
- A change of clothes for the morning.
- Any medications the doctor approved for you to continue taking.
- A book or reading material to help you relax.