If you find yourself falling asleep later and later each night—even when you try to stick to a schedule—you’re not alone. For some people, the internal body clock doesn’t run on a 24-hour day. This can lead to a condition known as Non-24-Hour Sleep-Wake Disorder (N24SWD).
It’s especially common among people who are totally blind, but it can affect sighted individuals too. If you often feel like you’re “out of sync” with the rest of the world, N24SWD could be why.
Common Signs of N24SWD
You fall asleep and wake up later each day.
You can’t fall asleep or wake up at normal times—even when you want to.
You feel sleepy during the day and struggle to stay alert.
Some days you sleep well, but other days are marked by insomnia or oversleeping.
You feel like your body is on its own time zone.
Why Does This Happen?
Your body has a natural clock—called the circadian rhythm—that tells you when to sleep and wake up. Most people’s clocks reset every 24 hours, thanks to light signals from the environment.
But in people with N24SWD, this clock runs longer—maybe 24.5 or even 25 hours. Over time, that small difference adds up, shifting your sleep-wake cycle further and further out of sync.
For people who are totally blind, the lack of light signals makes it hard to reset this rhythm. But sighted people can experience it too—due to neurological differences, genetics, or unknown reasons.
How Is N24SWD Diagnosed?
You don’t need fancy equipment to start the process. Diagnosis usually begins by tracking your sleep patterns over several weeks using:
A sleep diary or wearable sleep tracker (actigraphy)
Blood or saliva tests to check melatonin levels
A talk with a sleep specialist to rule out other causes
What Can You Do About It?
Good news—treatment can help you regain control of your sleep. Here are some of the most effective strategies:
Light Therapy:
Bright light at specific times each day can help reset your body clock.
Melatonin Supplements:
A small, properly timed dose of melatonin can guide your sleep schedule.
Behavioral Changes:
Keeping a strict wake-up time, sticking to a routine, and avoiding screens at night can make a big difference.
Gradual Sleep Shifts (Chronotherapy):
Sometimes, gradually adjusting your bedtime and wake time can help align your internal rhythm.
Can I Live Normally With N24SWD?
Yes, you absolutely can. With the right plan, many people with N24SWD return to a more predictable sleep pattern and feel much better during the day. The key is knowing what’s happening and getting support that works for you.
Ready to Reclaim Your Sleep?
If your sleep seems out of control or you’re tired of struggling to fit into a 24-hour world, you’re not imagining things—and you’re not alone. Help is available.
Zoe Psychiatry and Sleep Medicine specializes in identifying and treating sleep disorders like N24SWD. Call us or book an appointment online today and start your journey to better sleep and better days.
