Like Dr Tze Yeong, top of my mind would be to rule out Obstructive Sleep Apnoea (OSA), which is a fairly common problem, especially amongst obese patients.
Falling asleep is regulated by two primary processes:
- Your body’s circadian rhythm, which causes an increase in sleepiness twice over a 24-hour period (in general, from midnight to 7 am, and between 1 pm – 4 pm)
- Your physiologic need for sleep, which is increased by sleep loss and sleep disruption.
Excessive daytime sleepiness/unintended sleep episodes can result if you’ve got disturbances to either of these sleep-regulating mechanisms.
The most common causes are:
- Primary sleep disorders (eg. OSA, insomnia)
- Medical conditions that disrupt sleep (eg. bronchitis, asthma, heart failure, and painful conditions such as arthritis/back pain)
- Side effects of medication/drugs (eg. caffeine, alcohol and nicotine)
- Lifestyle factors (eg. shift work)
Is this something I should worry about?
The main worry with falling asleep unexpectedly is life-threatening car crashes (if you drive) and industrial accidents.
It can also result in impairment to your work performance.
It’s for these reasons that I’d suggest for you to visit your polyclinic GP. He will be able to rule out causes for your unintended sleep episodes, and refer you to a specialist, if necessary.
Cheers
